fix(core): preserve event routing semantics

CONTEXT.md

@@ -141,6 +141,7 @@ _Avoid_: Response envelope
 - Promise streaming methods return a lazy `AsyncIterable` directly rather than a Promise-wrapped stream object. Iteration opens the connection, `AbortSignal` cancels it, and ending iteration closes the underlying request; the Effect emitter analogously returns `Stream` directly.
 - Promise SSE connection establishment, declared HTTP failures, and infrastructure failures occur during `AsyncIterable` iteration, beginning with its first `next()` call, rather than during synchronous method construction.
 - Neither generated streaming runtime automatically reconnects after disconnection. Promise `AsyncIterable` and Effect `Stream` fail explicitly; live consumers refresh and resubscribe, while durable sequence-based resume remains explicit composition above the generated client.
+- Event definition durability is authoritative for published payloads. Durable definitions publish and decode only with commit metadata (`aggregateID`, `seq`, and `version`); live definitions forbid that metadata. Core's pre-commit payload without an assigned sequence is a separate internal type and never reaches subscribers or projectors.
 - Promise client construction is synchronous and network-free. It requires `baseUrl`, defaults to `globalThis.fetch`, accepts client-level headers, and merges them with per-call header overrides.
 - Effect client construction accepts an explicit `baseUrl` and obtains `HttpClient.HttpClient` from the Effect environment. It does not install fetch or duplicate per-call transport policy; callers transform/provide the client for headers, tracing, retries, recording, and tests, while fiber interruption owns cancellation.
 - Promise and Effect emitters each own their generated public type modules. The **SDK Contract IR**, not a physically shared generated type package, is the common source; this permits zero-Effect wire types and rich decoded Effect types to evolve independently.

packages/app/src/pages/layout-new.tsx

@@ -3,12 +3,18 @@ import { useNavigate, useParams } from "@solidjs/router"
 import { DebugBar } from "@/components/debug-bar"
 import { HelpButton } from "@/components/help-button"
 import { Titlebar, type TitlebarUpdate } from "@/components/titlebar"
+import { useCommand } from "@/context/command"
+import { useDialog } from "@opencode-ai/ui/context/dialog"
+import { useLanguage } from "@/context/language"
 import { useNotification } from "@/context/notification"
 import { usePlatform } from "@/context/platform"
 import { setNavigate } from "@/utils/notification-click"
 import { setV2Toast, ToastRegion } from "@/utils/toast"
 
 export default function NewLayout(props: ParentProps) {
+  const command = useCommand()
+  const dialog = useDialog()
+  const language = useLanguage()
   const platform = usePlatform()
   const notification = useNotification()
   const navigate = useNavigate()
@@ -22,6 +28,20 @@ export default function NewLayout(props: ParentProps) {
     notification.session.markViewed(params.id)
   })
 
+  command.register("layout", () => [
+    {
+      id: "settings.open",
+      title: language.t("command.settings.open"),
+      category: language.t("command.category.settings"),
+      keybind: "mod+comma",
+      onSelect: () => {
+        void import("@/components/settings-v2").then((x) => {
+          dialog.show(() => <x.DialogSettings />)
+        })
+      },
+    },
+  ])
+
   const update: TitlebarUpdate = {
     version: () => {
       const state = platform.updater?.state()

packages/app/src/pages/new-session.tsx

@@ -26,7 +26,7 @@ export default function NewSessionPage() {
   const serverSync = useServerSync()
   const comments = useComments()
   const route = useSessionKey()
-  const [searchParams, setSearchParams] = useSearchParams<{ prompt?: string }>()
+  const [searchParams, setSearchParams] = useSearchParams<{ draftId?: string; prompt?: string }>()
 
   let inputRef: HTMLDivElement | undefined
 

packages/core/src/event.ts

@@ -2,7 +2,14 @@ export * as EventV2 from "./event"
 
 import { Cause, Context, Effect, Layer, Option, PubSub, Schema, Stream } from "effect"
 import { Event } from "@opencode-ai/schema/event"
-import type { Data, Definition, Payload } from "@opencode-ai/schema/event"
+import type {
+  Data,
+  Definition,
+  DurableDefinition,
+  LiveDefinition,
+  Payload,
+  UncommittedPayload,
+} from "@opencode-ai/schema/event"
 import { and, asc, eq, gt } from "drizzle-orm"
 import { Database } from "./database/database"
 import { EventSequenceTable, EventTable } from "./event/sql"
@@ -124,8 +131,25 @@ export const layerWith = (options?: LayerOptions) =>
       )
 
       function commitDurableEvent(
-        definition: Definition,
-        event: Payload,
+        definition: DurableDefinition,
+        event: UncommittedPayload<DurableDefinition>,
+        input: undefined,
+        commit?: (seq: number) => Effect.Effect<void>,
+      ): Effect.Effect<Payload<DurableDefinition>>
+      function commitDurableEvent(
+        definition: DurableDefinition,
+        event: UncommittedPayload<DurableDefinition>,
+        input: {
+          readonly seq: number
+          readonly aggregateID: string
+          readonly ownerID?: string
+          readonly strictOwner?: boolean
+        },
+        commit?: (seq: number) => Effect.Effect<void>,
+      ): Effect.Effect<Payload<DurableDefinition> | undefined>
+      function commitDurableEvent(
+        definition: DurableDefinition,
+        event: UncommittedPayload<DurableDefinition>,
         input?: {
           readonly seq: number
           readonly aggregateID: string
@@ -135,7 +159,7 @@ export const layerWith = (options?: LayerOptions) =>
         commit?: (seq: number) => Effect.Effect<void>,
       ) {
         return Effect.gen(function* () {
-          const durable = definition?.durable
+          const durable = definition.durable
           if (durable) {
             const aggregateID = (event.data as Record<string, unknown>)[durable.aggregate]
             if (typeof aggregateID !== "string") {
@@ -200,7 +224,7 @@ export const layerWith = (options?: LayerOptions) =>
                                   .run()
                                   .pipe(Effect.orDie)
                               }
-                              return
+                              return undefined
                             }
                             yield* Effect.die(
                               new InvalidDurableEventError({
@@ -210,7 +234,7 @@ export const layerWith = (options?: LayerOptions) =>
                             )
                           }
                           if (input && row?.ownerID && row.ownerID !== input.ownerID) {
-                            return
+                            return undefined
                           }
                           const seq = input?.seq ?? latest + 1
                           if (input && seq !== latest + 1) {
@@ -234,10 +258,10 @@ export const layerWith = (options?: LayerOptions) =>
                                 message: `Event ${event.id} already exists at aggregate ${stored.aggregateID} sequence ${stored.seq}`,
                               }),
                             )
-                          const committed = {
+                          const committed: Payload<DurableDefinition> = {
                             ...event,
                             durable: { aggregateID, seq, version: durable.version },
-                          } as Payload
+                          }
                           for (const projector of list) {
                             yield* projector(committed)
                           }
@@ -267,14 +291,14 @@ export const layerWith = (options?: LayerOptions) =>
                             ])
                             .run()
                             .pipe(Effect.orDie)
-                          return { aggregateID, seq }
+                          return committed
                         }),
                       { behavior: "immediate" },
                     )
                     .pipe(Effect.orDie)
                   if (committed) {
                     yield* Effect.forEach(
-                      pubsub.durable.get(committed.aggregateID) ?? [],
+                      pubsub.durable.get(committed.durable.aggregateID) ?? [],
                       (wake) => PubSub.publish(wake, undefined),
                       { discard: true },
                     )
@@ -287,35 +311,6 @@ export const layerWith = (options?: LayerOptions) =>
         })
       }
 
-      function publishEvent<D extends Definition>(definition: D, event: Payload<D>, commit?: PublishOptions["commit"]) {
-        return Effect.gen(function* () {
-          if (!definition?.durable && commit)
-            return yield* Effect.die(
-              new InvalidDurableEventError({
-                type: event.type,
-                message: "Local commit hooks require a durable event",
-              }),
-            )
-          if (definition?.durable) {
-            const committed = yield* commitDurableEvent(definition, event as Payload, undefined, commit)
-            if (committed) {
-              event = {
-                ...event,
-                durable: {
-                  aggregateID: committed.aggregateID,
-                  seq: committed.seq,
-                  version: definition.durable.version,
-                },
-              }
-              yield* notify(event as Payload, true)
-              return event
-            }
-          }
-          yield* notify(event as Payload, false)
-          return event
-        })
-      }
-
       const observe = (event: Payload, observer: (event: Payload) => Effect.Effect<void>) =>
         Effect.suspend(() => observer(event)).pipe(
           Effect.catchCauseIf(
@@ -337,7 +332,12 @@ export const layerWith = (options?: LayerOptions) =>
         })
       }
 
-      function publish<D extends Definition>(definition: D, data: Data<D>, options?: PublishOptions) {
+      function publish<D extends Definition>(
+        definition: D,
+        data: Data<D>,
+        options?: PublishOptions,
+      ): Effect.Effect<Payload<D>>
+      function publish(definition: Definition, data: unknown, options?: PublishOptions): Effect.Effect<Payload> {
         return Effect.gen(function* () {
           const serviceLocation = Option.getOrUndefined(yield* Effect.serviceOption(Location.Service))
           const location =
@@ -345,17 +345,34 @@ export const layerWith = (options?: LayerOptions) =>
             (serviceLocation
               ? { directory: serviceLocation.directory, workspaceID: serviceLocation.workspaceID }
               : undefined)
-          return yield* publishEvent(
-            definition,
-            {
+          if (definition.durable) {
+            const event: UncommittedPayload<DurableDefinition> = {
               id: options?.id ?? ID.create(),
               ...(options?.metadata ? { metadata: options.metadata } : {}),
               type: definition.type,
               ...(location ? { location } : {}),
               data,
-            } as Payload<D>,
-            options?.commit,
-          )
+            }
+            const committed = yield* commitDurableEvent(definition, event, undefined, options?.commit)
+            yield* notify(committed, true)
+            return committed
+          }
+          if (options?.commit)
+            return yield* Effect.die(
+              new InvalidDurableEventError({
+                type: definition.type,
+                message: "Local commit hooks require a durable event",
+              }),
+            )
+          const event: Payload<LiveDefinition> = {
+            id: options?.id ?? ID.create(),
+            ...(options?.metadata ? { metadata: options.metadata } : {}),
+            type: definition.type,
+            ...(location ? { location } : {}),
+            data,
+          }
+          yield* notify(event, false)
+          return event
         })
       }
 
@@ -370,11 +387,11 @@ export const layerWith = (options?: LayerOptions) =>
               new InvalidDurableEventError({ type: event.type, message: `Unknown durable event type ${event.type}` }),
             )
           } else {
-            const payload = {
+            const payload: UncommittedPayload<DurableDefinition> = {
               id: event.id,
               type: definition.type,
               data: Schema.decodeUnknownSync(definition.data)(event.data),
-            } as Payload
+            }
             const committed = yield* commitDurableEvent(definition, payload, {
               seq: event.seq,
               aggregateID: event.aggregateID,
@@ -382,17 +399,7 @@ export const layerWith = (options?: LayerOptions) =>
               strictOwner: options?.strictOwner,
             })
             if (committed && options?.publish) {
-              yield* notify(
-                {
-                  ...payload,
-                  durable: {
-                    aggregateID: committed.aggregateID,
-                    seq: committed.seq,
-                    version: definition.durable.version,
-                  },
-                },
-                true,
-              )
+              yield* notify(committed, true)
             }
           }
         })
@@ -459,7 +466,7 @@ export const layerWith = (options?: LayerOptions) =>
 
       const streamAll = (): Stream.Stream<Payload> => Stream.fromPubSub(pubsub.all)
 
-      const decodeSerializedEvent = (event: SerializedEvent) => {
+      const decodeSerializedEvent = (event: SerializedEvent): Payload<DurableDefinition> => {
         const definition = Durable.get(event.type)
         if (!definition?.durable) {
           throw new InvalidDurableEventError({ type: event.type, message: `Unknown durable event type ${event.type}` })

packages/core/src/plugin.ts

@@ -1,8 +1,8 @@
 export * as PluginV2 from "./plugin"
 
 import { Context, Deferred, Effect, Exit, Layer, Scope } from "effect"
-import type { Plugin } from "@opencode-ai/plugin/v2/effect"
-import { PluginEvent, PluginID } from "@opencode-ai/schema/plugin"
+import type { Plugin as PluginRuntime } from "@opencode-ai/plugin/v2/effect"
+import { Plugin } from "@opencode-ai/schema/plugin"
 import { AgentV2 } from "./agent"
 import { AISDK } from "./aisdk"
 import { Catalog } from "./catalog"
@@ -15,13 +15,12 @@ import { Reference } from "./reference"
 import { SkillV2 } from "./skill"
 import { State } from "./state"
 
-export const ID = PluginID
+export const ID = Plugin.ID
 export type ID = typeof ID.Type
-
-export const Event = PluginEvent
+export const Event = Plugin.Event
 
 export interface Interface {
-  readonly add: (id: ID, effect: Plugin["effect"]) => Effect.Effect<void>
+  readonly add: (id: ID, effect: PluginRuntime["effect"]) => Effect.Effect<void>
   readonly remove: (id: ID) => Effect.Effect<void>
   readonly wait: (id: ID) => Effect.Effect<void>
 }
@@ -38,9 +37,9 @@ export const layer = Layer.effect(
     const loading = new Set<ID>()
     const waiters = new Map<ID, Set<Deferred.Deferred<void>>>()
     const failures = new Map<ID, Exit.Exit<void, never>>()
-    let host: Parameters<Plugin["effect"]>[0]
+    let host: Parameters<PluginRuntime["effect"]>[0]
 
-    const add = Effect.fn("Plugin.add")(function* (id: ID, effect: Plugin["effect"]) {
+    const add = Effect.fn("Plugin.add")(function* (id: ID, effect: PluginRuntime["effect"]) {
       if (loading.has(id)) return yield* Effect.die(`Plugin load cycle detected for ${id}`)
 
       yield* locks.withLock(id)(

packages/core/src/project/copy.ts

@@ -13,7 +13,7 @@ import { Slug } from "../util/slug"
 import { EventV2 } from "../event"
 import { Database } from "../database/database"
 import { Location } from "../location"
-import { ProjectDirectoriesEvent } from "@opencode-ai/schema/project-directories"
+import { Event } from "@opencode-ai/schema/project-directories"
 import { ProjectCopy } from "@opencode-ai/schema/project-copy"
 
 export const StrategyID = ProjectCopy.StrategyID
@@ -96,7 +96,7 @@ export interface Strategy {
   readonly list: (directory: AbsolutePath) => Effect.Effect<ListEntry[], Git.WorktreeError | DirectoryUnavailableError>
 }
 
-export const Event = ProjectDirectoriesEvent
+export { Event }
 
 export interface Interface {
   readonly register: (strategy: Strategy) => Effect.Effect<void, DuplicateStrategyError>

packages/core/src/project/directories.ts

@@ -4,7 +4,7 @@ import { and, asc, desc, eq, isNotNull, isNull, ne, or } from "drizzle-orm"
 import { Context, Effect, Layer, Schema } from "effect"
 import { Database } from "../database/database"
 import { LayerNode } from "../effect/layer-node"
-import { AbsolutePath, optionalOmitUndefined } from "../schema"
+import { AbsolutePath, optional } from "../schema"
 import { ProjectSchema } from "./schema"
 import { ProjectDirectoryTable } from "./sql"
 import type { EffectDrizzleSqlite } from "@opencode-ai/effect-drizzle-sqlite"
@@ -39,7 +39,7 @@ export type ListInput = typeof ListInput.Type
 export const ListOutput = Schema.Array(
   Schema.Struct({
     directory: AbsolutePath,
-    strategy: optionalOmitUndefined(Schema.String),
+    strategy: optional(Schema.String),
   }),
 ).annotate({ identifier: "Project.Directories" })
 export type ListOutput = typeof ListOutput.Type

packages/core/src/pty.ts

@@ -2,7 +2,7 @@ export * as Pty from "./pty"
 
 import type { Disp, Proc } from "#pty"
 import { Context, Effect, Layer, Schema, Types } from "effect"
-import { PtyEvent, PtyInfo, Pty } from "@opencode-ai/schema/pty"
+import { Pty } from "@opencode-ai/schema/pty"
 import { Config } from "./config"
 import { EventV2 } from "./event"
 import { Location } from "./location"
@@ -35,8 +35,7 @@ type Active = {
   listeners: Disp[]
 }
 
-export const Info = PtyInfo
-
+export const Info = Pty.Info
 export type Info = Types.DeepMutable<typeof Info.Type>
 
 export const CreateInput = Pty.CreateInput
@@ -47,6 +46,8 @@ export const UpdateInput = Pty.UpdateInput
 
 export type UpdateInput = Types.DeepMutable<typeof UpdateInput.Type>
 
+export const Event = Pty.Event
+
 export type AttachInput = {
   // Absolute output cursor to replay from. -1 tails from the current end; omitted replays the full retained buffer.
   readonly cursor?: number
@@ -75,8 +76,6 @@ export class ExitedError extends Schema.TaggedErrorClass<ExitedError>()("Pty.Exi
   ptyID: PtyID,
 }) {}
 
-export const Event = PtyEvent
-
 export interface Interface {
   readonly list: () => Effect.Effect<Info[]>
   readonly get: (id: PtyID) => Effect.Effect<Info, NotFoundError>

packages/core/src/schema.ts

@@ -3,21 +3,13 @@ import {
   AbsolutePath,
   DateTimeUtcFromMillis,
   NonNegativeInt,
-  optionalOmitUndefined,
+  optional,
   PositiveInt,
   RelativePath,
-  withStatics,
+  statics,
 } from "@opencode-ai/schema/schema"
 
-export {
-  AbsolutePath,
-  DateTimeUtcFromMillis,
-  NonNegativeInt,
-  optionalOmitUndefined,
-  PositiveInt,
-  RelativePath,
-  withStatics,
-}
+export { AbsolutePath, DateTimeUtcFromMillis, NonNegativeInt, optional, PositiveInt, RelativePath, statics }
 
 /**
  * Strip `readonly` from a nested type. Stand-in for `effect`'s `Types.DeepMutable`

packages/core/src/session/context-epoch.ts

@@ -9,7 +9,7 @@ import { ContextSnapshotDecodeError } from "./error"
 import { SessionEvent } from "./event"
 import { SessionHistory } from "./history"
 import { SessionInput } from "./input"
-import { SessionMessageID } from "./message-id"
+import { SessionMessage } from "./message"
 import { SessionSchema } from "./schema"
 import { SessionContextEpochTable } from "./sql"
 
@@ -71,7 +71,7 @@ const prepareOnce = Effect.fnUntraced(function* (
 
   yield* events.publish(
     SessionEvent.ContextUpdated,
-    { sessionID, messageID: SessionMessageID.ID.create(), timestamp: yield* DateTime.now, text: result.text },
+    { sessionID, messageID: SessionMessage.ID.create(), timestamp: yield* DateTime.now, text: result.text },
     { commit: () => advance(db, sessionID, result.snapshot).pipe(Effect.orDie) },
   )
   return { baseline: stored.baseline, baselineSeq: stored.baseline_seq }

packages/core/src/session/info.ts

@@ -8,7 +8,7 @@ import { AbsolutePath, RelativePath } from "../schema"
 import { WorkspaceV2 } from "../workspace"
 import { SessionSchema } from "./schema"
 import { SessionTable } from "./sql"
-import { SessionMessageID } from "./message-id"
+import { SessionMessage } from "./message"
 import { Snapshot } from "../snapshot"
 
 export function fromRow(row: typeof SessionTable.$inferSelect): SessionSchema.Info {
@@ -40,7 +40,7 @@ export function fromRow(row: typeof SessionTable.$inferSelect): SessionSchema.In
       workspaceID: row.workspace_id ? WorkspaceV2.ID.make(row.workspace_id) : undefined,
     }),
     subpath: row.path ? RelativePath.make(row.path) : undefined,
-    revert: row.revert ? { ...row.revert, messageID: SessionMessageID.ID.make(row.revert.messageID) } : undefined,
+    revert: row.revert ? { ...row.revert, messageID: SessionMessage.ID.make(row.revert.messageID) } : undefined,
     time: {
       created: DateTime.makeUnsafe(row.time_created),
       updated: DateTime.makeUnsafe(row.time_updated),

packages/core/src/session/message-id.ts

@@ -1,2 +0,0 @@
-export * as SessionMessageID from "./message-id"
-export { ID } from "@opencode-ai/schema/session-message-id"

packages/core/src/session/projector.ts

@@ -15,7 +15,6 @@ import { WorkspaceV2 } from "../workspace"
 import { SessionContextEpoch } from "./context-epoch"
 import { MessageTable, PartTable, SessionInputTable, SessionMessageTable, SessionTable } from "./sql"
 import type { DeepMutable } from "../schema"
-import { SessionMessageID } from "./message-id"
 
 type DatabaseService = Database.Interface["db"]
 
@@ -67,7 +66,7 @@ function sessionRow(info: SessionV1.SessionInfo): typeof SessionTable.$inferInse
     tokens_reasoning: (info.tokens ?? { reasoning: 0 }).reasoning,
     tokens_cache_read: (info.tokens ?? { cache: { read: 0 } }).cache.read,
     tokens_cache_write: (info.tokens ?? { cache: { write: 0 } }).cache.write,
-    revert: info.revert ? { ...info.revert, messageID: SessionMessageID.ID.make(info.revert.messageID) } : null,
+    revert: info.revert ? { ...info.revert, messageID: SessionMessage.ID.make(info.revert.messageID) } : null,
     permission: info.permission ? [...info.permission] : undefined,
     time_created: info.time.created,
     time_updated: info.time.updated,

packages/core/src/session/todo.ts

@@ -2,15 +2,14 @@ export * as SessionTodo from "./todo"
 
 import { asc, eq } from "drizzle-orm"
 import { Context, Effect, Layer } from "effect"
-import { SessionTodo, SessionTodoInfo } from "@opencode-ai/schema/session-todo"
+import { SessionTodo } from "@opencode-ai/schema/session-todo"
 import { Database } from "../database/database"
 import { EventV2 } from "../event"
 import { SessionSchema } from "./schema"
 import { TodoTable } from "./sql"
 
-export const Info = SessionTodoInfo
+export const Info = SessionTodo.Info
 export type Info = typeof Info.Type
-
 export const Event = SessionTodo.Event
 
 export interface Interface {

packages/core/test/event.test.ts

@@ -116,7 +116,7 @@ describe("EventV2", () => {
       const event = yield* events.publish(VersionedMessage, { id: "one", text: "hello" })
 
       expect(event.type).toBe("test.versioned")
-      expect(event.durable?.version).toBe(2)
+      expect(event.durable.version).toBe(2)
     }),
   )
 
@@ -138,6 +138,50 @@ describe("EventV2", () => {
     }),
   )
 
+  it.effect("preserves same-type projector routing across durable versions", () =>
+    Effect.gen(function* () {
+      const events = yield* EventV2.Service
+      const historical = EventV2.define({
+        type: "test.projector-version",
+        durable: { version: 1, aggregate: "id" },
+        schema: { id: Schema.String },
+      })
+      const current = EventV2.define({
+        type: "test.projector-version",
+        durable: { version: 2, aggregate: "id" },
+        schema: { id: Schema.String },
+      })
+      const received = new Array<EventV2.Payload>()
+      yield* events.project(historical, (event) => Effect.sync(() => received.push(event)))
+
+      const published = yield* events.publish(current, { id: "aggregate" })
+
+      expect(received).toEqual([published])
+    }),
+  )
+
+  it.effect("preserves same-type subscription routing across durable versions", () =>
+    Effect.gen(function* () {
+      const events = yield* EventV2.Service
+      const historical = EventV2.define({
+        type: "test.subscription-version",
+        durable: { version: 1, aggregate: "id" },
+        schema: { id: Schema.String },
+      })
+      const current = EventV2.define({
+        type: "test.subscription-version",
+        durable: { version: 2, aggregate: "id" },
+        schema: { id: Schema.String },
+      })
+      const fiber = yield* events.subscribe(historical).pipe(Stream.take(1), Stream.runCollect, Effect.forkScoped)
+      yield* Effect.yieldNow
+
+      const published = yield* events.publish(current, { id: "aggregate" })
+
+      expect(Array.from(yield* Fiber.join(fiber))).toEqual([published])
+    }),
+  )
+
   it.effect("publishes to typed and wildcard subscriptions", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
@@ -764,7 +808,7 @@ describe("EventV2", () => {
       const replayed = {
         id: published.id,
         type: EventV2.versionedType(DurableMessage.type, 1),
-        seq: published.durable!.seq,
+        seq: published.durable.seq,
         aggregateID,
         data: published.data,
       }

packages/core/test/session-runner-tool-events.test.ts

@@ -17,7 +17,14 @@ const capture = () => {
   const events = EventV2.Service.of({
     publish: (definition, data) =>
       Effect.sync(() => {
-        const event = { id: EventV2.ID.create(), type: definition.type, data } as EventV2.Payload<typeof definition>
+        const event = {
+          id: EventV2.ID.create(),
+          type: definition.type,
+          ...(definition.durable
+            ? { durable: { aggregateID: sessionID, seq: published.length, version: definition.durable.version } }
+            : {}),
+          data,
+        } as EventV2.Payload<typeof definition>
         published.push({
           type: definition.durable
             ? EventV2.versionedType(definition.type, definition.durable.version)

packages/core/test/shared-schema.test.ts

@@ -9,6 +9,8 @@ import { Model } from "@opencode-ai/schema/model"
 import { AgentAttachment, FileAttachment, Prompt, Source } from "@opencode-ai/schema/prompt"
 import { Provider } from "@opencode-ai/schema/provider"
 import { Project } from "@opencode-ai/schema/project"
+import { ProjectDirectories } from "@opencode-ai/schema/project-directories"
+import { PermissionV1 } from "@opencode-ai/schema/permission-v1"
 import { Session } from "@opencode-ai/schema/session"
 import { SessionInput } from "@opencode-ai/schema/session-input"
 import { SessionMessage } from "@opencode-ai/schema/session-message"
@@ -20,10 +22,14 @@ import { FileSystem } from "@opencode-ai/schema/filesystem"
 import { Integration } from "@opencode-ai/schema/integration"
 import { LLM } from "@opencode-ai/schema/llm"
 import { Permission } from "@opencode-ai/schema/permission"
+import { Plugin } from "@opencode-ai/schema/plugin"
+import { Pty } from "@opencode-ai/schema/pty"
 import { Reference } from "@opencode-ai/schema/reference"
+import { SessionTodo } from "@opencode-ai/schema/session-todo"
 import { Skill } from "@opencode-ai/schema/skill"
-import { AbsolutePath, DateTimeUtcFromMillis } from "@opencode-ai/schema/schema"
+import { AbsolutePath, DateTimeUtcFromMillis, optional, statics } from "@opencode-ai/schema/schema"
 import { ProviderV2 } from "@opencode-ai/core/provider"
+import { PluginV2 } from "@opencode-ai/core/plugin"
 
 test("Core reuses the canonical shared schemas", async () => {
   const [
@@ -35,13 +41,18 @@ test("Core reuses the canonical shared schemas", async () => {
     coreLocation,
     coreLLM,
     corePermission,
+    corePermissionV1,
+    coreProjectCopy,
+    corePty,
     coreProject,
     coreReference,
     coreSessionInput,
     coreSessionMessage,
+    coreSessionTodo,
     corePrompt,
     coreSkill,
     coreV2Schema,
+    coreSchema,
     coreWorkspace,
   ] = await Promise.all([
     import("@opencode-ai/core/command"),
@@ -52,13 +63,18 @@ test("Core reuses the canonical shared schemas", async () => {
     import("@opencode-ai/core/location"),
     import("@opencode-ai/llm"),
     import("@opencode-ai/core/permission"),
+    import("@opencode-ai/core/v1/permission"),
+    import("@opencode-ai/core/project/copy"),
+    import("@opencode-ai/core/pty"),
     import("@opencode-ai/core/project/schema"),
     import("@opencode-ai/core/reference"),
     import("@opencode-ai/core/session/input"),
     import("@opencode-ai/core/session/message"),
+    import("@opencode-ai/core/session/todo"),
     import("@opencode-ai/core/session/prompt"),
     import("@opencode-ai/core/skill"),
     import("@opencode-ai/core/v2-schema"),
+    import("@opencode-ai/core/schema"),
     import("@opencode-ai/core/workspace"),
   ])
 
@@ -111,6 +127,12 @@ test("Core reuses the canonical shared schemas", async () => {
     [corePermission.Effect, Permission.Effect],
     [corePermission.Rule, Permission.Rule],
     [corePermission.Ruleset, Permission.Ruleset],
+    [corePermissionV1.Event, PermissionV1.Event],
+    [coreProjectCopy.Event, ProjectDirectories.Event],
+    [PluginV2.ID, Plugin.ID],
+    [PluginV2.Event, Plugin.Event],
+    [corePty.Info, Pty.Info],
+    [corePty.Event, Pty.Event],
     [coreProject.ID, Project.ID],
     [coreReference.LocalSource, Reference.LocalSource],
     [coreReference.GitSource, Reference.GitSource],
@@ -140,6 +162,8 @@ test("Core reuses the canonical shared schemas", async () => {
     [coreSessionMessage.Assistant, SessionMessage.Assistant],
     [coreSessionMessage.Compaction, SessionMessage.Compaction],
     [coreSessionMessage.Message, SessionMessage.Message],
+    [coreSessionTodo.Info, SessionTodo.Info],
+    [coreSessionTodo.Event, SessionTodo.Event],
     [corePrompt.Source, Source],
     [corePrompt.FileAttachment, FileAttachment],
     [corePrompt.AgentAttachment, AgentAttachment],
@@ -150,6 +174,8 @@ test("Core reuses the canonical shared schemas", async () => {
     [coreSkill.Source, Skill.Source],
     [coreSkill.Info, Skill.Info],
     [coreV2Schema.DateTimeUtcFromMillis, DateTimeUtcFromMillis],
+    [coreSchema.optional, optional],
+    [coreSchema.statics, statics],
     [coreWorkspace.ID, Workspace.ID],
   ]
   for (const [core, shared] of schemas) expect(core).toBe(shared)

packages/opencode/src/permission/index.ts

@@ -6,9 +6,8 @@ import { Deferred, Effect, Layer, Context } from "effect"
 import os from "os"
 import { PermissionV1 } from "@opencode-ai/core/v1/permission"
 import { EventV2Bridge } from "@/event-v2-bridge"
-import { PermissionV1Event } from "@opencode-ai/schema/permission-v1"
 
-export const Event = PermissionV1Event
+export const Event = PermissionV1.Event
 
 export interface Interface {
   readonly ask: (input: PermissionV1.AskInput) => Effect.Effect<void, PermissionV1.Error>

packages/opencode/src/provider/auth.ts

@@ -3,7 +3,7 @@ import type { AuthOAuthResult, Hooks } from "@opencode-ai/plugin"
 import { serviceUse } from "@opencode-ai/core/effect/service-use"
 import { Auth } from "@/auth"
 import { InstanceState } from "@/effect/instance-state"
-import { optionalOmitUndefined } from "@opencode-ai/core/schema"
+import { optional } from "@opencode-ai/core/schema"
 import { Plugin } from "../plugin"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { Array as Arr, Effect, Layer, Record, Result, Context, Schema } from "effect"
@@ -18,14 +18,14 @@ const TextPrompt = Schema.Struct({
   type: Schema.Literal("text"),
   key: Schema.String,
   message: Schema.String,
-  placeholder: optionalOmitUndefined(Schema.String),
-  when: optionalOmitUndefined(When),
+  placeholder: optional(Schema.String),
+  when: optional(When),
 })
 
 const SelectOption = Schema.Struct({
   label: Schema.String,
   value: Schema.String,
-  hint: optionalOmitUndefined(Schema.String),
+  hint: optional(Schema.String),
 })
 
 const SelectPrompt = Schema.Struct({
@@ -33,7 +33,7 @@ const SelectPrompt = Schema.Struct({
   key: Schema.String,
   message: Schema.String,
   options: Schema.Array(SelectOption),
-  when: optionalOmitUndefined(When),
+  when: optional(When),
 })
 
 const Prompt = Schema.Union([TextPrompt, SelectPrompt])
@@ -41,7 +41,7 @@ const Prompt = Schema.Union([TextPrompt, SelectPrompt])
 export class Method extends Schema.Class<Method>("ProviderAuthMethod")({
   type: Schema.Literals(["oauth", "api"]),
   label: Schema.String,
-  prompts: optionalOmitUndefined(Schema.Array(Prompt)),
+  prompts: optional(Schema.Array(Prompt)),
 }) {}
 
 export const Methods = Schema.Record(Schema.String, Schema.Array(Method))

packages/opencode/src/provider/provider.ts

@@ -24,7 +24,7 @@ import { InstanceState } from "@/effect/instance-state"
 import { EffectPromise } from "@/effect/promise"
 import { FSUtil } from "@opencode-ai/core/fs-util"
 import { isRecord } from "@/util/record"
-import { optionalOmitUndefined } from "@opencode-ai/core/schema"
+import { optional } from "@opencode-ai/core/schema"
 import { ProviderTransform } from "./transform"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { ModelV2 } from "@opencode-ai/core/model"
@@ -999,8 +999,8 @@ const ProviderCost = Schema.Struct({
   input: Schema.Finite,
   output: Schema.Finite,
   cache: ProviderCacheCost,
-  tiers: optionalOmitUndefined(Schema.Array(ProviderCostTier)),
-  experimentalOver200K: optionalOmitUndefined(
+  tiers: optional(Schema.Array(ProviderCostTier)),
+  experimentalOver200K: optional(
     Schema.Struct({
       input: Schema.Finite,
       output: Schema.Finite,
@@ -1011,7 +1011,7 @@ const ProviderCost = Schema.Struct({
 
 const ProviderLimit = Schema.Struct({
   context: Schema.Finite,
-  input: optionalOmitUndefined(Schema.Finite),
+  input: optional(Schema.Finite),
   output: Schema.Finite,
 })
 
@@ -1020,7 +1020,7 @@ export const Model = Schema.Struct({
   providerID: ProviderV2.ID,
   api: ProviderApiInfo,
   name: Schema.String,
-  family: optionalOmitUndefined(Schema.String),
+  family: optional(Schema.String),
   capabilities: ProviderCapabilities,
   cost: ProviderCost,
   limit: ProviderLimit,
@@ -1028,7 +1028,7 @@ export const Model = Schema.Struct({
   options: Schema.Record(Schema.String, Schema.Any),
   headers: Schema.Record(Schema.String, Schema.String),
   release_date: Schema.String,
-  variants: optionalOmitUndefined(Schema.Record(Schema.String, Schema.Record(Schema.String, Schema.Any))),
+  variants: optional(Schema.Record(Schema.String, Schema.Record(Schema.String, Schema.Any))),
 }).annotate({ identifier: "Model" })
 export type Model = Types.DeepMutable<Schema.Schema.Type<typeof Model>>
 
@@ -1037,7 +1037,7 @@ export const Info = Schema.Struct({
   name: Schema.String,
   source: Schema.Literals(["env", "config", "custom", "api"]),
   env: Schema.Array(Schema.String),
-  key: optionalOmitUndefined(Schema.String),
+  key: optional(Schema.String),
   options: Schema.Record(Schema.String, Schema.Any),
   models: Schema.Record(Schema.String, Model),
 }).annotate({ identifier: "Provider" })

packages/opencode/src/session/schema.ts

@@ -2,14 +2,14 @@ import { Schema } from "effect"
 
 import { Identifier } from "@/id/id"
 import { SessionV2 } from "@opencode-ai/core/session"
-import { withStatics } from "@opencode-ai/core/schema"
+import { statics } from "@opencode-ai/core/schema"
 
 export const SessionID = SessionV2.ID
 export type SessionID = Schema.Schema.Type<typeof SessionID>
 
 export const MessageID = Schema.String.check(Schema.isStartsWith("msg")).pipe(
   Schema.brand("MessageID"),
-  withStatics((s) => ({
+  statics((s) => ({
     ascending: (id?: string) => s.make(Identifier.ascending("message", id)),
   })),
 )
@@ -18,7 +18,7 @@ export type MessageID = Schema.Schema.Type<typeof MessageID>
 
 export const PartID = Schema.String.check(Schema.isStartsWith("prt")).pipe(
   Schema.brand("PartID"),
-  withStatics((s) => ({
+  statics((s) => ({
     ascending: (id?: string) => s.make(Identifier.ascending("part", id)),
   })),
 )

packages/opencode/src/session/session.ts

@@ -39,11 +39,11 @@ import { SessionID, MessageID, PartID } from "./schema"
 import type { Provider } from "@/provider/provider"
 import { Global } from "@opencode-ai/core/global"
 import { Effect, Layer, Option, Context, Schema, Types } from "effect"
-import { NonNegativeInt, optionalOmitUndefined } from "@opencode-ai/core/schema"
+import { NonNegativeInt, optional } from "@opencode-ai/core/schema"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { ModelV2 } from "@opencode-ai/core/model"
-import { SessionMessageID } from "@opencode-ai/schema/session-message-id"
+import { SessionMessage } from "@opencode-ai/schema/session-message"
 
 const runtime = makeRuntime(Database.Service, Database.defaultLayer)
 
@@ -146,7 +146,7 @@ export function toRow(info: Info) {
     tokens_cache_write: (info.tokens ?? EmptyTokens).cache.write,
     revert: info.revert
       ? {
-          messageID: SessionMessageID.ID.make(info.revert.messageID),
+          messageID: SessionMessage.ID.make(info.revert.messageID),
           partID: info.revert.partID,
           snapshot: info.revert.snapshot,
           diff: info.revert.diff,
@@ -178,7 +178,7 @@ const Summary = Schema.Struct({
   additions: Schema.Finite,
   deletions: Schema.Finite,
   files: Schema.Finite,
-  diffs: optionalOmitUndefined(Schema.Array(Snapshot.FileDiff)),
+  diffs: optional(Schema.Array(Snapshot.FileDiff)),
 })
 
 const Tokens = Schema.Struct({
@@ -204,21 +204,21 @@ export const ArchivedTimestamp = Schema.Finite
 const Time = Schema.Struct({
   created: NonNegativeInt,
   updated: NonNegativeInt,
-  compacting: optionalOmitUndefined(NonNegativeInt),
-  archived: optionalOmitUndefined(ArchivedTimestamp),
+  compacting: optional(NonNegativeInt),
+  archived: optional(ArchivedTimestamp),
 })
 
 const Revert = Schema.Struct({
   messageID: MessageID,
-  partID: optionalOmitUndefined(PartID),
-  snapshot: optionalOmitUndefined(Schema.String),
-  diff: optionalOmitUndefined(Schema.String),
+  partID: optional(PartID),
+  snapshot: optional(Schema.String),
+  diff: optional(Schema.String),
 })
 
 const Model = Schema.Struct({
   id: ModelV2.ID,
   providerID: ProviderV2.ID,
-  variant: optionalOmitUndefined(Schema.String),
+  variant: optional(Schema.String),
 })
 
 export const Metadata = Schema.Record(Schema.String, Schema.Any)
@@ -227,28 +227,28 @@ export const Info = Schema.Struct({
   id: SessionID,
   slug: Schema.String,
   projectID: ProjectV2.ID,
-  workspaceID: optionalOmitUndefined(WorkspaceV2.ID),
+  workspaceID: optional(WorkspaceV2.ID),
   directory: Schema.String,
-  path: optionalOmitUndefined(Schema.String),
-  parentID: optionalOmitUndefined(SessionID),
-  summary: optionalOmitUndefined(Summary),
-  cost: optionalOmitUndefined(Schema.Finite),
-  tokens: optionalOmitUndefined(Tokens),
-  share: optionalOmitUndefined(Share),
+  path: optional(Schema.String),
+  parentID: optional(SessionID),
+  summary: optional(Summary),
+  cost: optional(Schema.Finite),
+  tokens: optional(Tokens),
+  share: optional(Share),
   title: Schema.String,
-  agent: optionalOmitUndefined(Schema.String),
-  model: optionalOmitUndefined(Model),
+  agent: optional(Schema.String),
+  model: optional(Model),
   version: Schema.String,
-  metadata: optionalOmitUndefined(Metadata),
+  metadata: optional(Metadata),
   time: Time,
-  permission: optionalOmitUndefined(PermissionV1.Ruleset),
-  revert: optionalOmitUndefined(Revert),
+  permission: optional(PermissionV1.Ruleset),
+  revert: optional(Revert),
 }).annotate({ identifier: "Session" })
 export type Info = Types.DeepMutable<Schema.Schema.Type<typeof Info>>
 
 export const ProjectInfo = Schema.Struct({
   id: ProjectV2.ID,
-  name: optionalOmitUndefined(Schema.String),
+  name: optional(Schema.String),
   worktree: Schema.String,
 }).annotate({ identifier: "ProjectSummary" })
 export type ProjectInfo = Types.DeepMutable<Schema.Schema.Type<typeof ProjectInfo>>

packages/opencode/src/sync/schema.ts

@@ -1,11 +1,11 @@
 import { Schema } from "effect"
 
 import { Identifier } from "@/id/id"
-import { withStatics } from "@opencode-ai/core/schema"
+import { statics } from "@opencode-ai/core/schema"
 
 export const EventID = Schema.String.check(Schema.isStartsWith("evt")).pipe(
   Schema.brand("EventID"),
-  withStatics((s) => ({
+  statics((s) => ({
     ascending: (id?: string) => s.make(Identifier.ascending("event", id)),
   })),
 )

packages/opencode/src/tool/schema.ts

@@ -1,14 +1,14 @@
 import { Schema } from "effect"
 
 import { Identifier } from "@/id/id"
-import { withStatics } from "@opencode-ai/core/schema"
+import { statics } from "@opencode-ai/core/schema"
 
 const toolIdSchema = Schema.String.check(Schema.isStartsWith("tool")).pipe(Schema.brand("ToolID"))
 
 export type ToolID = typeof toolIdSchema.Type
 
 export const ToolID = toolIdSchema.pipe(
-  withStatics((schema: typeof toolIdSchema) => ({
+  statics((schema: typeof toolIdSchema) => ({
     ascending: (id?: string) => schema.make(Identifier.ascending("tool", id)),
   })),
 )

packages/opencode/test/server/httpapi-public-openapi.test.ts

@@ -99,6 +99,17 @@ describe("PublicApi OpenAPI v2 errors", () => {
     })
   })
 
+  test("documents durable metadata only on durable events", () => {
+    const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
+    const durable = spec.components.schemas.V2EventSessionCreated
+    const live = spec.components.schemas.V2EventSessionNextTextDelta
+
+    expect(durable?.required).toContain("durable")
+    expect(durable?.properties?.durable).toBeDefined()
+    expect(live?.required).not.toContain("durable")
+    expect(Reflect.get(live?.properties?.durable ?? {}, "not")).toEqual({})
+  })
+
   test("preserves /api auth responses", () => {
     const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
 

packages/opencode/test/server/httpapi-v2-location.test.ts

@@ -23,6 +23,7 @@ function request(route: string, directory: string, init: RequestInit = {}) {
 const Event = Schema.Struct({
   id: EventV2.ID,
   type: Schema.String,
+  durable: Schema.optional(Schema.Struct({ aggregateID: Schema.String, seq: Schema.Int, version: Schema.Int })),
   location: Schema.optional(Location.Ref),
   data: Schema.Unknown,
 })
@@ -81,12 +82,15 @@ describe("v2 location HttpApi", () => {
     const reader = response.body!.getReader()
     const connected = await readEvent(reader)
     expect(connected.type).toBe("server.connected")
+    expect(connected).not.toHaveProperty("durable")
     expect(connected.location).toBeUndefined()
 
     const created = await request("/session", publisher.path, { method: "POST" })
     expect(created.status).toBe(200)
+    const session = (await created.json()) as { id: string }
     expect(await readEventType(reader, "session.created")).toMatchObject({
       type: "session.created",
+      durable: { aggregateID: session.id, seq: 0, version: 1 },
       location: { directory: publisher.path },
       data: { sessionID: expect.any(String) },
     })

packages/opencode/test/v2/session-message-updater.test.ts

@@ -9,6 +9,12 @@ import { SessionEvent } from "@opencode-ai/core/session/event"
 import { SessionMessageUpdater } from "@opencode-ai/core/session/message-updater"
 import { SessionMessage } from "@opencode-ai/core/session/message"
 
+function durable(sessionID: SessionID, seq?: number): { aggregateID: SessionID; seq: number; version: 1 }
+function durable(sessionID: SessionID, seq: number, version: 2): { aggregateID: SessionID; seq: number; version: 2 }
+function durable(sessionID: SessionID, seq = 0, version: 1 | 2 = 1) {
+  return { aggregateID: sessionID, seq, version }
+}
+
 test.skip("step snapshots carry over to assistant messages", () => {
   const state: SessionMessageUpdater.MemoryState = { messages: [] }
   const sessionID = SessionID.make("session")
@@ -17,6 +23,7 @@ test.skip("step snapshots carry over to assistant messages", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID),
       type: "session.next.step.started",
       data: {
         sessionID,
@@ -38,6 +45,7 @@ test.skip("step snapshots carry over to assistant messages", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 1, 2),
       type: "session.next.step.ended",
       data: {
         sessionID,
@@ -70,6 +78,7 @@ test.skip("text ended populates assistant text content", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID),
       type: "session.next.step.started",
       data: {
         sessionID,
@@ -88,6 +97,7 @@ test.skip("text ended populates assistant text content", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 1),
       type: "session.next.text.started",
       data: {
         sessionID,
@@ -101,6 +111,7 @@ test.skip("text ended populates assistant text content", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 2),
       type: "session.next.text.ended",
       data: {
         sessionID,
@@ -126,6 +137,7 @@ test.skip("tool completion stores completed timestamp", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID),
       type: "session.next.step.started",
       data: {
         sessionID,
@@ -144,6 +156,7 @@ test.skip("tool completion stores completed timestamp", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 1),
       type: "session.next.tool.input.started",
       data: {
         sessionID,
@@ -158,6 +171,7 @@ test.skip("tool completion stores completed timestamp", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 2),
       type: "session.next.tool.called",
       data: {
         sessionID,
@@ -174,6 +188,7 @@ test.skip("tool completion stores completed timestamp", () => {
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 3),
       type: "session.next.tool.success",
       data: {
         sessionID,
@@ -204,6 +219,7 @@ test("compaction events reduce to compaction message only when completed", () =>
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id,
+      durable: durable(sessionID),
       type: "session.next.compaction.started",
       data: {
         sessionID,
@@ -245,6 +261,7 @@ test("compaction events reduce to compaction message only when completed", () =>
   Effect.runSync(
     SessionMessageUpdater.update(SessionMessageUpdater.memory(state), {
       id: EventV2.ID.create(),
+      durable: durable(sessionID, 3),
       type: "session.next.compaction.ended",
       data: {
         sessionID,

packages/protocol/src/groups/event.ts

@@ -8,24 +8,34 @@ import { HttpApiEndpoint, HttpApiGroup, OpenApi } from "effect/unstable/httpapi"
 const fields = {
   id: Event.ID,
   metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
-  durable: Schema.optional(Schema.Struct({ aggregateID: Schema.String, seq: Schema.Int, version: Schema.Int })),
   location: Schema.optional(Location.Ref),
 }
 
+const DurableEnvelope = Schema.Struct({ aggregateID: Schema.String, seq: Schema.Int, version: Schema.Int })
+
 const schema = (definitions: ReadonlyArray<Definition>) =>
   Schema.Union([
     ...definitions.map((definition) =>
-      Schema.Struct({
-        ...fields,
-        type: Schema.Literal(definition.type),
-        data: definition.data,
-      }).annotate({ identifier: `V2Event.${definition.type}` }),
+      definition.durable
+        ? Schema.Struct({
+            ...fields,
+            durable: DurableEnvelope,
+            type: Schema.Literal(definition.type),
+            data: definition.data,
+          }).annotate({ identifier: `V2Event.${definition.type}` })
+        : Schema.Struct({
+            ...fields,
+            durable: Schema.optional(Schema.Never),
+            type: Schema.Literal(definition.type),
+            data: definition.data,
+          }).annotate({ identifier: `V2Event.${definition.type}` }),
     ),
     ...(definitions.some((definition) => definition.type === "server.connected")
       ? []
       : [
           Schema.Struct({
             ...fields,
+            durable: Schema.optional(Schema.Never),
             type: Schema.Literal("server.connected"),
             data: Schema.Struct({}),
           }).annotate({ identifier: "V2Event.server.connected" }),
@@ -56,4 +66,5 @@ export const makeEventGroup = (definitions: ReadonlyArray<Definition>) => make(d
 
 const event = make(EventManifest.ServerDefinitions)
 export const EventGroup = event.group
-export type Event = typeof event.schema.Type
+export const EventSchema = event.schema
+export type Event = typeof EventSchema.Type

packages/protocol/src/groups/session.ts

@@ -3,7 +3,7 @@ import { SessionInput } from "@opencode-ai/schema/session-input"
 import { Prompt } from "@opencode-ai/schema/prompt"
 import { Session } from "@opencode-ai/schema/session"
 import { Project } from "@opencode-ai/schema/project"
-import { AbsolutePath, PositiveInt, RelativePath, withStatics } from "@opencode-ai/schema/schema"
+import { AbsolutePath, PositiveInt, RelativePath, statics } from "@opencode-ai/schema/schema"
 import { Workspace } from "@opencode-ai/schema/workspace"
 import { Context, Encoding, Result, Schema, Struct } from "effect"
 import { HttpApiEndpoint, HttpApiGroup, HttpApiMiddleware, HttpApiSchema, OpenApi } from "effect/unstable/httpapi"
@@ -62,7 +62,7 @@ const decodeSessionsCursor = Schema.decodeUnknownEffect(SessionsCursorJson)
 
 export const SessionsCursor = Schema.String.pipe(
   Schema.brand("SessionsCursor"),
-  withStatics((schema) => {
+  statics((schema) => {
     const make = schema.make.bind(schema)
     return {
       make: (input: typeof SessionsCursorInput.Type) => make(Encoding.encodeBase64Url(encodeSessionsCursor(input))),

packages/protocol/test/event.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, test } from "bun:test"
+import { Event } from "@opencode-ai/schema/event"
+import { Schema } from "effect"
+import { EventSchema } from "../src/groups/event"
+
+describe("EventSchema", () => {
+  test("requires durable metadata on durable events", () => {
+    expect(
+      Schema.is(EventSchema)({
+        id: Event.ID.create(),
+        type: "session.created",
+        data: { sessionID: "session" },
+      }),
+    ).toBe(false)
+  })
+
+  test("rejects durable metadata on live events", () => {
+    expect(
+      Schema.is(EventSchema)({
+        id: Event.ID.create(),
+        type: "server.connected",
+        durable: { aggregateID: "aggregate", seq: 0, version: 1 },
+        data: {},
+      }),
+    ).toBe(false)
+  })
+})

packages/schema/AGENTS.md

@@ -0,0 +1,88 @@
+# Schema Package Guide
+
+`@opencode-ai/schema` owns browser-safe wire and storage contracts shared by protocol, server, core, and generated SDKs. Keep runtime behavior, service layers, side effects, and host-local implementation details in the domain package that owns them.
+
+## Package Boundary
+
+- Preserve the dependency direction: `@opencode-ai/schema <- @opencode-ai/protocol <- @opencode-ai/server`.
+- Schema values should be serializable contract definitions, not service implementations or runtime registries.
+- A domain may keep a minimal public wire contract here when SDK generation needs it, but do not move the broader runtime model into Schema just because an event is public. `plugin.added` is the current example: Schema may own the minimum browser-safe event payload, while plugin runtime behavior stays outside Schema.
+- The root barrel exports canonical current domain contracts. Specialized event modules, manifests, infrastructure modules, and V1 contracts use direct entrypoints instead of becoming first-class root exports.
+
+## Current Versus V1
+
+- Current contracts are unversioned: use names like `Session`, `Permission`, `Question`, and identifiers like `Permission.Request`.
+- Legacy contracts retained for active compatibility, persistence, or migration are explicitly `V1`: use names like `SessionV1`, `PermissionV1`, and identifiers like `PermissionV1.Request`.
+- Do not preserve `V2` as the permanent name for the replacement architecture. Remove `V2` from current namespaces, brands, and identifiers as the contracts are normalized.
+- Retained V1 contracts should live under a dedicated `src/v1/` subtree once the V1 isolation PR runs. New/current code must not depend on that subtree.
+- V1 coexistence is temporary. Keep compatibility entrypoints only where migration requires them, and delete the V1 subtree when the legacy runtime is retired.
+- `@opencode-ai/protocol` and `@opencode-ai/sdk-next` are current `/api/...` surfaces.
+
+## Events
+
+- Classify event definitions by protocol role before adding them to a public manifest: `current`, `shared transitional`, or `V1-only`.
+- Being emitted by V1 is not enough to include an event in Protocol or SDK Next.
+- Keep clearly V1-only events, such as `message.updated` and `message.part.*`, out of the current Protocol/SDK Next event surface unless a current-client requirement is documented.
+- Keep compatibility events available only to the existing App/TUI/CLI compatibility surface while they are still needed.
+- Preserve a single canonical event definition. Do not duplicate definitions for generation convenience.
+
+## Module Shape
+
+- Use one canonical exported value for each contract. Avoid bridge aliases such as `PluginID`, `PluginEvent`, `PtyInfo`, `PtyEvent`, and `SessionTodoInfo`.
+- Prefer importing the schema module namespace and reading canonical members, for example `Plugin.ID` or `SessionTodo.Info`.
+- Core may compose Schema contracts with runtime behavior into a deliberate domain facade, but the facade must re-export the exact canonical Schema value. Do not create a second schema identity.
+- Use flat top-level exports plus the package's existing namespace projection pattern, for example `export * as SessionMessage from "./session-message"`.
+- Keep standalone ID modules only when they prevent real cycles or heavy dependency edges. Inline one-off IDs into their owning contract module when no cycle exists.
+
+## Naming
+
+- Exported schema values and namespace objects use `PascalCase`.
+- Schema-building functions and combinators use `camelCase`.
+- The package's static-method combinator is `statics(...)`.
+- Keep descriptive schema value names such as `PositiveInt`, `NonNegativeInt`, `AbsolutePath`, `RelativePath`, and `DateTimeUtcFromMillis`.
+
+## Optional Fields And Defaults
+
+- Use the package `optional(...)` helper for optional object properties, including nested structs and event payloads, so encoded objects omit `undefined` keys.
+- Use raw `Schema.optional(...)` only when preserving `undefined` as an explicitly encoded property is intentional and documented.
+- External convenience defaults are normally decode-only with `Schema.withDecodingDefault(...)`.
+- Add constructor defaults only when the domain value itself requires construction-time normalization.
+
+## Public Types
+
+- Public `Schema.Struct` records use same-name interfaces:
+
+  ```ts
+  export interface Info extends Schema.Schema.Type<typeof Info> {}
+  export const Info = Schema.Struct({ ... })
+  ```
+
+- Use type aliases for unions, scalars, arrays, branded scalar types, and event payload helper types.
+- Closed documented string sets use `Schema.Literals(...)`. If arbitrary strings are valid, document the field as arbitrary rather than listing a closed set.
+
+## Mutability
+
+- Public Schema contracts are readonly by default.
+- Do not use `Schema.mutable(...)` in public contracts for runtime convenience.
+- Runtime code that needs mutation should opt in at the boundary with `Types.DeepMutable`, a purpose-built draft type, or another explicit mutable API.
+
+## Unknown Values
+
+- Current public contracts avoid `Schema.Any`.
+- Use `Schema.Json` for values that must be JSON-serializable.
+- Use `Schema.Unknown` for genuinely opaque values that require consumer-side narrowing.
+- Keep `Schema.Any` only at an explicitly unsafe compatibility boundary with a documented reason.
+
+## IDs And Identifiers
+
+- Current ID constructors expose `create()`.
+- Directional constructors such as `ascending()` or `descending()` remain only where ordering semantics are part of the public contract or compatibility requires the old method.
+- New generated ID schemas must validate exactly the prefix they emit, including the underscore.
+- Do not tighten legacy loose ID validators without an explicit compatibility and migration decision; existing callers and tests may rely on accepted non-canonical IDs.
+- Reusable exported public schemas get stable, domain-qualified identifiers such as `Model.Ref` or `Agent.Color`.
+- Public schema identifiers and brands must be unique and stable. Private one-use nested schemas may remain anonymous.
+
+## Tests For Contract Changes
+
+- Add focused tests when changing contract behavior or generated surface.
+- Cover optional properties omitting `undefined`, no accidental current-contract `Schema.Any`, stable and unique public identifiers, exact facade/schema identity, and current Protocol manifests excluding V1-only events.

packages/schema/src/agent.ts

@@ -4,7 +4,7 @@ import { Schema } from "effect"
 import { Model } from "./model"
 import { Permission } from "./permission"
 import { Provider } from "./provider"
-import { PositiveInt, withStatics } from "./schema"
+import { PositiveInt, statics } from "./schema"
 
 export const ID = Schema.String.pipe(Schema.brand("AgentV2.ID"))
 export type ID = typeof ID.Type
@@ -30,7 +30,7 @@ export const Info = Schema.Struct({
 })
   .annotate({ identifier: "AgentV2.Info" })
   .pipe(
-    withStatics((schema) => ({
+    statics((schema) => ({
       empty: (id: ID) =>
         schema.make({ id, request: { headers: {}, body: {} }, mode: "all", hidden: false, permissions: [] }),
     })),

packages/schema/src/credential.ts

@@ -3,11 +3,11 @@ export * as Credential from "./credential"
 import { Schema } from "effect"
 import { IntegrationMethodID } from "./integration-id"
 import { ascending } from "./identifier"
-import { NonNegativeInt, withStatics } from "./schema"
+import { NonNegativeInt, statics } from "./schema"
 
 export const ID = Schema.String.pipe(
   Schema.brand("Credential.ID"),
-  withStatics((schema) => ({ create: () => schema.make("cred_" + ascending()) })),
+  statics((schema) => ({ create: () => schema.make("cred_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 

packages/schema/src/event.ts

@@ -3,70 +3,127 @@ export * as Event from "./event"
 import { Schema } from "effect"
 import { ascending } from "./identifier"
 import { Location } from "./location"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.check(Schema.isStartsWith("evt_")).pipe(
   Schema.brand("Event.ID"),
-  withStatics((schema) => ({ create: () => schema.make("evt_" + ascending()) })),
+  statics((schema) => ({ create: () => schema.make("evt_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 
-export type Definition<
+export type DurableOptions = {
+  readonly version: number
+  readonly aggregate: string
+}
+
+export type DurableEnvelope = {
+  readonly aggregateID: string
+  readonly seq: number
+  readonly version: number
+}
+
+const PublishedDurableEnvelope = Schema.Struct({
+  aggregateID: Schema.String,
+  seq: Schema.Number,
+  version: Schema.Number,
+})
+const NoDurableEnvelope = Schema.optional(Schema.Never)
+
+export type LiveDefinition<
   Type extends string = string,
   DataSchema extends Schema.Codec<unknown, unknown> = Schema.Codec<unknown, unknown>,
 > = Schema.Top & {
   readonly type: Type
-  readonly durable?: {
-    readonly version: number
-    readonly aggregate: string
-  }
   readonly data: DataSchema
+  readonly durable?: never
 }
 
+export type DurableDefinition<
+  Type extends string = string,
+  DataSchema extends Schema.Codec<unknown, unknown> = Schema.Codec<unknown, unknown>,
+  Durability extends DurableOptions = DurableOptions,
+> = Schema.Top & {
+  readonly type: Type
+  readonly data: DataSchema
+  readonly durable: Durability
+}
+
+export type Definition<
+  Type extends string = string,
+  DataSchema extends Schema.Codec<unknown, unknown> = Schema.Codec<unknown, unknown>,
+> = LiveDefinition<Type, DataSchema> | DurableDefinition<Type, DataSchema>
+
 export type Data<D extends Definition> = Schema.Schema.Type<D["data"]>
 
-export type Payload<D extends Definition = Definition> = {
-  readonly id: ID
-  readonly type: D["type"]
-  readonly data: Data<D>
-  readonly durable?: {
-    readonly aggregateID: string
-    readonly seq: number
-    readonly version: number
-  }
-  readonly location?: Location.Ref
-  readonly metadata?: Record<string, unknown>
-}
+export type UncommittedPayload<D extends Definition = Definition> = D extends Definition
+  ? {
+      readonly id: ID
+      readonly type: D["type"]
+      readonly data: Data<D>
+      readonly location?: Location.Ref
+      readonly metadata?: Record<string, unknown>
+    }
+  : never
+
+export type PublishedPayload<D extends Definition = Definition> = D extends DurableDefinition
+  ? UncommittedPayload<D> & { readonly durable: DurableEnvelope }
+  : D extends LiveDefinition
+    ? UncommittedPayload<D> & { readonly durable?: never }
+    : never
+
+export type Payload<D extends Definition = Definition> = PublishedPayload<D>
+
+type LiveEventSchema<
+  Type extends string,
+  Fields extends Readonly<Record<PropertyKey, Schema.Codec<unknown, unknown>>>,
+> = Schema.Schema<PublishedPayload<LiveDefinition<Type, Schema.Struct<Fields>>>> &
+  LiveDefinition<Type, Schema.Struct<Fields>>
+
+type DurableEventSchema<
+  Type extends string,
+  Fields extends Readonly<Record<PropertyKey, Schema.Codec<unknown, unknown>>>,
+  Durability extends DurableOptions,
+> = Schema.Schema<PublishedPayload<DurableDefinition<Type, Schema.Struct<Fields>, Durability>>> &
+  DurableDefinition<Type, Schema.Struct<Fields>, Durability>
 
 export function define<
   const Type extends string,
   Fields extends Readonly<Record<PropertyKey, Schema.Codec<unknown, unknown>>>,
+>(input: { readonly type: Type; readonly durable?: never; readonly schema: Fields }): LiveEventSchema<Type, Fields>
+export function define<
+  const Type extends string,
+  Fields extends Readonly<Record<PropertyKey, Schema.Codec<unknown, unknown>>>,
+  const Durability extends DurableOptions,
 >(input: {
   readonly type: Type
-  readonly durable?: {
-    readonly version: number
-    readonly aggregate: string
-  }
+  readonly durable: Durability
   readonly schema: Fields
-}): Schema.Schema<Payload<Definition<Type, Schema.Struct<Fields>>>> & Definition<Type, Schema.Struct<Fields>> {
+}): DurableEventSchema<Type, Fields, Durability>
+export function define(input: {
+  readonly type: string
+  readonly durable?: DurableOptions
+  readonly schema: Readonly<Record<PropertyKey, Schema.Codec<unknown, unknown>>>
+}): Schema.Top {
   const data = Schema.Struct(input.schema)
-  return Object.assign(
-    Schema.Struct({
-      id: ID,
-      metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
-      type: Schema.Literal(input.type),
-      durable: Schema.optional(
-        Schema.Struct({ aggregateID: Schema.String, seq: Schema.Number, version: Schema.Number }),
-      ),
-      location: Schema.optional(Location.Ref),
-      data,
-    }).annotate({ identifier: input.type }),
-    {
-      type: input.type,
-      ...(input.durable === undefined ? {} : { durable: input.durable }),
-      data,
-    },
-  ) as Schema.Schema<Payload<Definition<Type, Schema.Struct<Fields>>>> & Definition<Type, Schema.Struct<Fields>>
+  const fields = {
+    id: ID,
+    metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
+    type: Schema.Literal(input.type),
+    location: Schema.optional(Location.Ref),
+    data,
+  }
+  if (input.durable) {
+    return Object.assign(
+      Schema.Struct({ ...fields, durable: PublishedDurableEnvelope }).annotate({
+        identifier: input.type,
+      }),
+      { type: input.type, durable: input.durable, data },
+    )
+  }
+  return Object.assign(Schema.Struct({ ...fields, durable: NoDurableEnvelope }).annotate({ identifier: input.type }), {
+    type: input.type,
+    data,
+  })
 }
 
 export function inventory<const Definitions extends ReadonlyArray<Definition>>(...definitions: Definitions) {
@@ -103,7 +160,7 @@ export function durable(definitions: ReadonlyArray<Definition>) {
       if (result.has(key)) throw new Error(`Duplicate durable event definition for ${key}`)
       result.set(key, definition)
       return result
-    }, new Map<string, Definition>()),
+    }, new Map<string, DurableDefinition>()),
   )
 }
 

packages/schema/src/integration.ts

@@ -4,7 +4,7 @@ import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { Connection } from "./connection"
 import { ascending } from "./identifier"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 import { IntegrationID, IntegrationMethodID } from "./integration-id"
 
 export const ID = IntegrationID
@@ -102,7 +102,7 @@ export class Info extends Schema.Class<Info>("Integration.Info")({
 
 export const AttemptID = Schema.String.pipe(
   Schema.brand("Integration.AttemptID"),
-  withStatics((schema) => ({ create: () => schema.make("con_" + ascending()) })),
+  statics((schema) => ({ create: () => schema.make("con_" + ascending()) })),
 )
 export type AttemptID = typeof AttemptID.Type
 

packages/schema/src/location.ts

@@ -1,7 +1,7 @@
 export * as Location from "./location"
 
 import { Effect, Schema } from "effect"
-import { AbsolutePath, optionalOmitUndefined } from "./schema"
+import { AbsolutePath, optional } from "./schema"
 import { ProjectID } from "./project-id"
 import { WorkspaceID } from "./workspace-id"
 
@@ -16,7 +16,7 @@ export const Ref = Schema.Struct({
 
 export class Info extends Schema.Class<Info>("Location.Info")({
   directory: AbsolutePath,
-  workspaceID: optionalOmitUndefined(WorkspaceID),
+  workspaceID: optional(WorkspaceID),
   project: Schema.Struct({
     id: ProjectID,
     directory: AbsolutePath,

packages/schema/src/model.ts

@@ -2,7 +2,7 @@ export * as Model from "./model"
 
 import { Schema } from "effect"
 import { Provider } from "./provider"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.pipe(Schema.brand("ModelV2.ID"))
 export type ID = typeof ID.Type
@@ -83,7 +83,7 @@ export const Info = Schema.Struct({
 })
   .annotate({ identifier: "ModelV2.Info" })
   .pipe(
-    withStatics((schema) => ({
+    statics((schema) => ({
       empty: (providerID: Provider.ID, modelID: ID) =>
         schema.make({
           id: modelID,

packages/schema/src/permission-saved.ts

@@ -3,11 +3,11 @@ export * as PermissionSaved from "./permission-saved"
 import { Schema } from "effect"
 import { ascending } from "./identifier"
 import { ProjectID } from "./project-id"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.pipe(
   Schema.brand("PermissionSaved.ID"),
-  withStatics((schema) => ({ create: () => schema.make("psv_" + ascending()) })),
+  statics((schema) => ({ create: () => schema.make("psv_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 

packages/schema/src/permission-v1.ts

@@ -4,12 +4,12 @@ import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { ascending } from "./identifier"
 import { Project } from "./project"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 import { SessionID } from "./session-id"
 
 export const ID = Schema.String.check(Schema.isStartsWith("per")).pipe(
   Schema.brand("PermissionID"),
-  withStatics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "per_" + ascending()) })),
+  statics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "per_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 
@@ -64,4 +64,3 @@ const Replied = define({
   schema: { sessionID: SessionID, requestID: ID, reply: Reply },
 })
 export const Event = { Asked, Replied, Definitions: inventory(Asked, Replied) }
-export const PermissionV1Event = Event

packages/schema/src/permission.ts

@@ -4,11 +4,11 @@ import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { ascending } from "./identifier"
 import { SessionID } from "./session-id"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.check(Schema.isStartsWith("per")).pipe(
   Schema.brand("PermissionV2.ID"),
-  withStatics((schema) => ({ create: (id?: string) => schema.make(id ?? "per_" + ascending()) })),
+  statics((schema) => ({ create: (id?: string) => schema.make(id ?? "per_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 

packages/schema/src/plugin.ts

@@ -5,11 +5,9 @@ import { define, inventory } from "./event"
 
 export const ID = Schema.String.pipe(Schema.brand("Plugin.ID"))
 export type ID = typeof ID.Type
-export const PluginID = ID
 
 const Added = define({
   type: "plugin.added",
   schema: { id: ID },
 })
 export const Event = { Added, Definitions: inventory(Added) }
-export const PluginEvent = Event

packages/schema/src/project-directories.ts

@@ -8,4 +8,3 @@ const Updated = define({
   schema: { projectID: Project.ID },
 })
 export const Event = { Updated, Definitions: inventory(Updated) }
-export const ProjectDirectoriesEvent = Event

packages/schema/src/project-id.ts

@@ -1,8 +1,8 @@
 import { Schema } from "effect"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ProjectID = Schema.String.pipe(
   Schema.brand("Project.ID"),
-  withStatics((schema) => ({ global: schema.make("global") })),
+  statics((schema) => ({ global: schema.make("global") })),
 )
 export type ProjectID = typeof ProjectID.Type

packages/schema/src/project.ts

@@ -2,7 +2,7 @@ export * as Project from "./project"
 
 import { Schema } from "effect"
 import { define, inventory } from "./event"
-import { NonNegativeInt, optionalOmitUndefined } from "./schema"
+import { NonNegativeInt, optional } from "./schema"
 import { ProjectID } from "./project-id"
 
 export const ID = ProjectID
@@ -10,28 +10,28 @@ export type ID = typeof ID.Type
 
 export const Vcs = Schema.Literal("git")
 export const Icon = Schema.Struct({
-  url: optionalOmitUndefined(Schema.String),
-  override: optionalOmitUndefined(Schema.String),
-  color: optionalOmitUndefined(Schema.String),
+  url: optional(Schema.String),
+  override: optional(Schema.String),
+  color: optional(Schema.String),
 })
 export const Commands = Schema.Struct({
-  start: optionalOmitUndefined(
+  start: optional(
     Schema.String.annotate({ description: "Startup script to run when creating a new workspace (worktree)" }),
   ),
 })
 export const Time = Schema.Struct({
   created: NonNegativeInt,
   updated: NonNegativeInt,
-  initialized: optionalOmitUndefined(NonNegativeInt),
+  initialized: optional(NonNegativeInt),
 })
 
 export const Info = Schema.Struct({
   id: ID,
   worktree: Schema.String,
-  vcs: optionalOmitUndefined(Vcs),
-  name: optionalOmitUndefined(Schema.String),
-  icon: optionalOmitUndefined(Icon),
-  commands: optionalOmitUndefined(Commands),
+  vcs: optional(Vcs),
+  name: optional(Schema.String),
+  icon: optional(Icon),
+  commands: optional(Commands),
   time: Time,
   sandboxes: Schema.Array(Schema.String),
 }).annotate({ identifier: "Project" })

packages/schema/src/prompt.ts

@@ -1,5 +1,5 @@
 import { Schema } from "effect"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export interface Source extends Schema.Schema.Type<typeof Source> {}
 export const Source = Schema.Struct({
@@ -18,7 +18,7 @@ export const FileAttachment = Schema.Struct({
 })
   .annotate({ identifier: "Prompt.FileAttachment" })
   .pipe(
-    withStatics((schema) => ({
+    statics((schema) => ({
       create: (input: FileAttachment) =>
         schema.make({
           uri: input.uri,
@@ -44,7 +44,7 @@ export const Prompt = Schema.Struct({
 })
   .annotate({ identifier: "Prompt" })
   .pipe(
-    withStatics((schema) => ({
+    statics((schema) => ({
       equivalence: Schema.toEquivalence(schema),
       fromUserMessage: (input: Pick<Prompt, "text" | "files" | "agents">) =>
         schema.make({

packages/schema/src/provider.ts

@@ -2,11 +2,11 @@ export * as Provider from "./provider"
 
 import { Schema } from "effect"
 import { Integration } from "./integration"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.pipe(
   Schema.brand("ProviderV2.ID"),
-  withStatics((schema) => ({
+  statics((schema) => ({
     opencode: schema.make("opencode"),
     anthropic: schema.make("anthropic"),
     openai: schema.make("openai"),
@@ -57,7 +57,7 @@ export const Info = Schema.Struct({
 })
   .annotate({ identifier: "ProviderV2.Info" })
   .pipe(
-    withStatics((schema) => ({
+    statics((schema) => ({
       empty: (id: ID) =>
         schema.make({
           id,

packages/schema/src/pty.ts

@@ -3,13 +3,12 @@ export * as Pty from "./pty"
 import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { ascending } from "./identifier"
-import { NonNegativeInt, PositiveInt } from "./schema"
-import { withStatics } from "./schema"
+import { NonNegativeInt, PositiveInt, statics } from "./schema"
 
 const IDSchema = Schema.String.check(Schema.isStartsWith("pty")).pipe(Schema.brand("PtyID"))
 
 export const ID = IDSchema.pipe(
-  withStatics((schema: typeof IDSchema) => ({
+  statics((schema: typeof IDSchema) => ({
     ascending: (id?: string) => schema.make(id ?? "pty_" + ascending()),
   })),
 )
@@ -25,14 +24,12 @@ export const Info = Schema.Struct({
   pid: NonNegativeInt,
   exitCode: Schema.optional(NonNegativeInt),
 }).annotate({ identifier: "Pty" })
-export const PtyInfo = Info
 
 const Created = define({ type: "pty.created", schema: { info: Info } })
 const Updated = define({ type: "pty.updated", schema: { info: Info } })
 const Exited = define({ type: "pty.exited", schema: { id: ID, exitCode: NonNegativeInt } })
 const Deleted = define({ type: "pty.deleted", schema: { id: ID } })
 export const Event = { Created, Updated, Exited, Deleted, Definitions: inventory(Created, Updated, Exited, Deleted) }
-export const PtyEvent = Event
 
 export const CreateInput = Schema.Struct({
   command: Schema.optional(Schema.String),

packages/schema/src/question-v1.ts

@@ -3,13 +3,13 @@ export * as QuestionV1 from "./question-v1"
 import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { ascending } from "./identifier"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 import { SessionID } from "./session-id"
 import { SessionV1 } from "./session-v1"
 
 export const ID = Schema.String.check(Schema.isStartsWith("que")).pipe(
   Schema.brand("QuestionID"),
-  withStatics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "que_" + ascending()) })),
+  statics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "que_" + ascending()) })),
 )
 
 export const Option = Schema.Struct({

packages/schema/src/question.ts

@@ -4,11 +4,11 @@ import { Schema } from "effect"
 import { define, inventory } from "./event"
 import { ascending } from "./identifier"
 import { SessionID } from "./session-id"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const ID = Schema.String.check(Schema.isStartsWith("que")).pipe(
   Schema.brand("QuestionV2.ID"),
-  withStatics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "que_" + ascending()) })),
+  statics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "que_" + ascending()) })),
 )
 export type ID = typeof ID.Type
 

packages/schema/src/revert.ts

@@ -2,7 +2,7 @@ export * as Revert from "./revert"
 
 import { Schema } from "effect"
 import { NonNegativeInt, RelativePath } from "./schema"
-import { SessionMessageID } from "./session-message-id"
+import { SessionMessage } from "./session-message"
 
 export const FileDiff = Schema.Struct({
   path: RelativePath,
@@ -14,7 +14,7 @@ export const FileDiff = Schema.Struct({
 export type FileDiff = typeof FileDiff.Type
 
 export const State = Schema.Struct({
-  messageID: SessionMessageID.ID,
+  messageID: SessionMessage.ID,
   partID: Schema.String.pipe(Schema.optional),
   snapshot: Schema.String.pipe(Schema.optional),
   diff: Schema.String.pipe(Schema.optional),

packages/schema/src/schema.ts

@@ -9,7 +9,7 @@ export type RelativePath = typeof RelativePath.Type
 export const AbsolutePath = Schema.String.pipe(Schema.brand("AbsolutePath"))
 export type AbsolutePath = typeof AbsolutePath.Type
 
-export const optionalOmitUndefined = <S extends Schema.Top>(schema: S) =>
+export const optional = <S extends Schema.Top>(schema: S) =>
   Schema.optionalKey(schema).pipe(
     Schema.decodeTo(Schema.optional(schema), {
       decode: SchemaGetter.passthrough({ strict: false }),
@@ -17,7 +17,7 @@ export const optionalOmitUndefined = <S extends Schema.Top>(schema: S) =>
     }),
   )
 
-export const withStatics =
+export const statics =
   <S extends object, M extends Record<string, unknown>>(methods: (schema: S) => M) =>
   (schema: S): S & M =>
     Object.assign(schema, methods(schema))

packages/schema/src/session-event.ts

@@ -9,7 +9,6 @@ import { DateTimeUtcFromMillis, NonNegativeInt, RelativePath } from "./schema"
 import { FileAttachment, Prompt } from "./prompt"
 import { SessionID } from "./session-id"
 import { Location } from "./location"
-import { SessionMessageID } from "./session-message-id"
 import { SessionMessage } from "./session-message"
 import { Revert } from "./revert"
 
@@ -30,7 +29,7 @@ const Base = {
 }
 const PromptFields = {
   ...Base,
-  messageID: SessionMessageID.ID,
+  messageID: SessionMessage.ID,
   prompt: Prompt,
   delivery: Delivery,
 }
@@ -56,7 +55,7 @@ export const AgentSwitched = Event.define({
   ...options,
   schema: {
     ...Base,
-    messageID: SessionMessageID.ID,
+    messageID: SessionMessage.ID,
     agent: Schema.String,
   },
 })
@@ -67,7 +66,7 @@ export const ModelSwitched = Event.define({
   ...options,
   schema: {
     ...Base,
-    messageID: SessionMessageID.ID,
+    messageID: SessionMessage.ID,
     model: Model.Ref,
   },
 })
@@ -103,7 +102,7 @@ export const ContextUpdated = Event.define({
   ...options,
   schema: {
     ...Base,
-    messageID: SessionMessageID.ID,
+    messageID: SessionMessage.ID,
     text: Schema.String,
   },
 })
@@ -114,7 +113,7 @@ export const Synthetic = Event.define({
   ...options,
   schema: {
     ...Base,
-    messageID: SessionMessageID.ID,
+    messageID: SessionMessage.ID,
     text: Schema.String,
   },
 })
@@ -126,7 +125,7 @@ export namespace Shell {
     ...options,
     schema: {
       ...Base,
-      messageID: SessionMessageID.ID,
+      messageID: SessionMessage.ID,
       callID: Schema.String,
       command: Schema.String,
     },
@@ -151,7 +150,7 @@ export namespace Step {
     ...options,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       agent: Schema.String,
       model: Model.Ref,
       snapshot: Schema.String.pipe(Schema.optional),
@@ -164,7 +163,7 @@ export namespace Step {
     ...stepSettlementOptions,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       finish: Schema.String,
       cost: Schema.Finite,
       tokens: Schema.Struct({
@@ -187,7 +186,7 @@ export namespace Step {
     ...stepSettlementOptions,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       error: UnknownError,
     },
   })
@@ -200,7 +199,7 @@ export namespace Text {
     ...options,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       textID: Schema.String,
     },
   })
@@ -211,7 +210,7 @@ export namespace Text {
     type: "session.next.text.delta",
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       textID: Schema.String,
       delta: Schema.String,
     },
@@ -223,7 +222,7 @@ export namespace Text {
     ...options,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       textID: Schema.String,
       text: Schema.String,
     },
@@ -237,7 +236,7 @@ export namespace Reasoning {
     ...options,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       reasoningID: Schema.String,
       providerMetadata: ProviderMetadata.pipe(Schema.optional),
     },
@@ -249,7 +248,7 @@ export namespace Reasoning {
     type: "session.next.reasoning.delta",
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       reasoningID: Schema.String,
       delta: Schema.String,
     },
@@ -261,7 +260,7 @@ export namespace Reasoning {
     ...options,
     schema: {
       ...Base,
-      assistantMessageID: SessionMessageID.ID,
+      assistantMessageID: SessionMessage.ID,
       reasoningID: Schema.String,
       text: Schema.String,
       providerMetadata: ProviderMetadata.pipe(Schema.optional),
@@ -273,7 +272,7 @@ export namespace Reasoning {
 export namespace Tool {
   const ToolBase = {
     ...Base,
-    assistantMessageID: SessionMessageID.ID,
+    assistantMessageID: SessionMessage.ID,
     callID: Schema.String,
   }
 
@@ -401,7 +400,7 @@ export namespace Compaction {
     ...options,
     schema: {
       ...Base,
-      messageID: SessionMessageID.ID,
+      messageID: SessionMessage.ID,
       reason: Schema.Union([Schema.Literal("auto"), Schema.Literal("manual")]),
     },
   })
@@ -411,7 +410,7 @@ export namespace Compaction {
     type: "session.next.compaction.delta",
     schema: {
       ...Base,
-      messageID: SessionMessageID.ID,
+      messageID: SessionMessage.ID,
       text: Schema.String,
     },
   })
@@ -422,7 +421,7 @@ export namespace Compaction {
     ...options,
     schema: {
       ...Base,
-      messageID: SessionMessageID.ID,
+      messageID: SessionMessage.ID,
       reason: Started.data.fields.reason,
       text: Schema.String,
       recent: Schema.String,
@@ -441,7 +440,7 @@ export namespace RevertEvent {
   export const Committed = Event.define({
     type: "session.next.revert.committed",
     ...options,
-    schema: { ...Base, messageID: SessionMessageID.ID },
+    schema: { ...Base, messageID: SessionMessage.ID },
   })
 }
 

packages/schema/src/session-id.ts

@@ -1,10 +1,10 @@
 import { Schema } from "effect"
 import { descending } from "./identifier"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const SessionID = Schema.String.check(Schema.isStartsWith("ses")).pipe(
   Schema.brand("SessionID"),
-  withStatics((schema) => {
+  statics((schema) => {
     const create = () => schema.make("ses_" + descending())
     return {
       create,

packages/schema/src/session-input.ts

@@ -5,7 +5,7 @@ import { Prompt } from "./prompt"
 import { DateTimeUtcFromMillis, NonNegativeInt } from "./schema"
 import { SessionDelivery } from "./session-delivery"
 import { SessionID } from "./session-id"
-import { SessionMessageID } from "./session-message-id"
+import { SessionMessage } from "./session-message"
 
 export const Delivery = SessionDelivery.Delivery
 export type Delivery = SessionDelivery.Delivery
@@ -13,7 +13,7 @@ export type Delivery = SessionDelivery.Delivery
 export interface Admitted extends Schema.Schema.Type<typeof Admitted> {}
 export const Admitted = Schema.Struct({
   admittedSeq: NonNegativeInt,
-  id: SessionMessageID.ID,
+  id: SessionMessage.ID,
   sessionID: SessionID,
   prompt: Prompt,
   delivery: Delivery,

packages/schema/src/session-message-id.ts

@@ -1,11 +0,0 @@
-export * as SessionMessageID from "./session-message-id"
-
-import { Schema } from "effect"
-import { ascending } from "./identifier"
-import { withStatics } from "./schema"
-
-export const ID = Schema.String.check(Schema.isStartsWith("msg_")).pipe(
-  Schema.brand("Session.Message.ID"),
-  withStatics((schema) => ({ create: () => schema.make("msg_" + ascending()) })),
-)
-export type ID = typeof ID.Type

packages/schema/src/session-message.ts

@@ -4,12 +4,15 @@ import { Schema } from "effect"
 import { ProviderMetadata, ToolContent } from "./llm"
 import { Model } from "./model"
 import { FileAttachment, Prompt } from "./prompt"
-import { DateTimeUtcFromMillis, RelativePath } from "./schema"
+import { DateTimeUtcFromMillis, RelativePath, statics } from "./schema"
 import { SessionID } from "./session-id"
-import { SessionMessageID } from "./session-message-id"
+import { ascending } from "./identifier"
 
-export const ID = SessionMessageID.ID
-export type ID = SessionMessageID.ID
+export const ID = Schema.String.check(Schema.isStartsWith("msg_")).pipe(
+  Schema.brand("Session.Message.ID"),
+  statics((schema) => ({ create: () => schema.make("msg_" + ascending()) })),
+)
+export type ID = typeof ID.Type
 
 export interface UnknownError extends Schema.Schema.Type<typeof UnknownError> {}
 export const UnknownError = Schema.Struct({

packages/schema/src/session-todo.ts

@@ -12,7 +12,6 @@ export const Info = Schema.Struct({
   priority: Schema.String.annotate({ description: "Priority level of the task: high, medium, low" }),
 }).annotate({ identifier: "Todo" })
 export type Info = typeof Info.Type
-export const SessionTodoInfo = Info
 
 const Updated = define({
   type: "todo.updated",

packages/schema/src/session-v1.ts

@@ -7,7 +7,7 @@ import { PermissionV1 } from "./permission-v1"
 import { Project } from "./project"
 import { Provider } from "./provider"
 import { Model } from "./model"
-import { NonNegativeInt, optionalOmitUndefined, withStatics } from "./schema"
+import { NonNegativeInt, optional, statics } from "./schema"
 import { ascending } from "./identifier"
 import { SessionID } from "./session-id"
 import { WorkspaceID } from "./workspace-id"
@@ -16,13 +16,13 @@ const Timestamp = Schema.Finite.check(Schema.isGreaterThanOrEqualTo(0))
 
 export const MessageID = Schema.String.check(Schema.isStartsWith("msg")).pipe(
   Schema.brand("MessageID"),
-  withStatics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "msg_" + ascending()) })),
+  statics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "msg_" + ascending()) })),
 )
 export type MessageID = typeof MessageID.Type
 
 export const PartID = Schema.String.check(Schema.isStartsWith("prt")).pipe(
   Schema.brand("PartID"),
-  withStatics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "prt_" + ascending()) })),
+  statics((schema) => ({ ascending: (id?: string) => schema.make(id ?? "prt_" + ascending()) })),
 )
 export type PartID = typeof PartID.Type
 
@@ -510,7 +510,7 @@ const SessionSummary = Schema.Struct({
   additions: Schema.Finite,
   deletions: Schema.Finite,
   files: Schema.Finite,
-  diffs: optionalOmitUndefined(Schema.Array(FileDiff.Info)),
+  diffs: optional(Schema.Array(FileDiff.Info)),
 })
 
 const SessionTokens = Schema.Struct({
@@ -529,42 +529,42 @@ const SessionShare = Schema.Struct({
 
 const SessionRevert = Schema.Struct({
   messageID: MessageID,
-  partID: optionalOmitUndefined(PartID),
-  snapshot: optionalOmitUndefined(Schema.String),
-  diff: optionalOmitUndefined(Schema.String),
+  partID: optional(PartID),
+  snapshot: optional(Schema.String),
+  diff: optional(Schema.String),
 })
 
 const SessionModel = Schema.Struct({
   id: Model.ID,
   providerID: Provider.ID,
-  variant: optionalOmitUndefined(Schema.String),
+  variant: optional(Schema.String),
 })
 
 export const SessionInfo = Schema.Struct({
   id: SessionID,
   slug: Schema.String,
   projectID: Project.ID,
-  workspaceID: optionalOmitUndefined(WorkspaceID),
+  workspaceID: optional(WorkspaceID),
   directory: Schema.String,
-  path: optionalOmitUndefined(Schema.String),
-  parentID: optionalOmitUndefined(SessionID),
-  summary: optionalOmitUndefined(SessionSummary),
-  cost: optionalOmitUndefined(Schema.Finite),
-  tokens: optionalOmitUndefined(SessionTokens),
-  share: optionalOmitUndefined(SessionShare),
+  path: optional(Schema.String),
+  parentID: optional(SessionID),
+  summary: optional(SessionSummary),
+  cost: optional(Schema.Finite),
+  tokens: optional(SessionTokens),
+  share: optional(SessionShare),
   title: Schema.String,
-  agent: optionalOmitUndefined(Schema.String),
-  model: optionalOmitUndefined(SessionModel),
+  agent: optional(Schema.String),
+  model: optional(SessionModel),
   version: Schema.String,
-  metadata: optionalOmitUndefined(Schema.Record(Schema.String, Schema.Any)),
+  metadata: optional(Schema.Record(Schema.String, Schema.Any)),
   time: Schema.Struct({
     created: NonNegativeInt,
     updated: NonNegativeInt,
-    compacting: optionalOmitUndefined(NonNegativeInt),
-    archived: optionalOmitUndefined(Schema.Finite),
+    compacting: optional(NonNegativeInt),
+    archived: optional(Schema.Finite),
   }),
-  permission: optionalOmitUndefined(PermissionV1.Ruleset),
-  revert: optionalOmitUndefined(SessionRevert),
+  permission: optional(PermissionV1.Ruleset),
+  revert: optional(SessionRevert),
 }).annotate({ identifier: "Session" })
 export type SessionInfo = typeof SessionInfo.Type
 

packages/schema/src/session.ts

@@ -5,7 +5,7 @@ import { Agent } from "./agent"
 import { Location } from "./location"
 import { Model } from "./model"
 import { Project } from "./project"
-import { DateTimeUtcFromMillis, optionalOmitUndefined, RelativePath } from "./schema"
+import { DateTimeUtcFromMillis, optional, RelativePath } from "./schema"
 import { SessionEvent } from "./session-event"
 import { SessionID } from "./session-id"
 import { Revert } from "./revert"
@@ -18,7 +18,7 @@ export const Event = SessionEvent
 export interface Info extends Schema.Schema.Type<typeof Info> {}
 export const Info = Schema.Struct({
   id: ID,
-  parentID: ID.pipe(optionalOmitUndefined),
+  parentID: ID.pipe(optional),
   projectID: Project.ID,
   agent: Agent.ID.pipe(Schema.optional),
   model: Model.Ref.pipe(Schema.optional),

packages/schema/src/workspace-id.ts

@@ -1,10 +1,10 @@
 import { Schema } from "effect"
 import { ascending } from "./identifier"
-import { withStatics } from "./schema"
+import { statics } from "./schema"
 
 export const WorkspaceID = Schema.String.check(Schema.isStartsWith("wrk")).pipe(
   Schema.brand("WorkspaceV2.ID"),
-  withStatics((schema) => {
+  statics((schema) => {
     const create = () => schema.make("wrk_" + ascending())
     return {
       ascending: (id?: string) => {

packages/schema/test/event.test.ts

@@ -34,4 +34,96 @@ describe("public event schemas", () => {
 
     expect(Event.durable([definition]).get("test.durable.1")).toBe(definition)
   })
+
+  test("durable definitions require published commit metadata", () => {
+    const definition = Event.define({
+      type: "test.durable",
+      durable: { aggregate: "id", version: 1 },
+      schema: { id: Schema.String },
+    })
+    const payload: typeof definition.Type = {
+      id: Event.ID.create(),
+      type: definition.type,
+      durable: { aggregateID: "aggregate", seq: 0, version: 1 },
+      data: { id: "aggregate" },
+    }
+
+    expect(Schema.is(definition)(payload)).toBe(true)
+    expect(
+      Schema.is(definition)({
+        id: Event.ID.create(),
+        type: definition.type,
+        data: { id: "aggregate" },
+      }),
+    ).toBe(false)
+    // @ts-expect-error Published durable payloads require commit metadata.
+    const missing: typeof definition.Type = { id: Event.ID.create(), type: definition.type, data: { id: "aggregate" } }
+    void missing
+  })
+
+  test("live definitions reject durable commit metadata", () => {
+    const definition = Event.define({
+      type: "test.live",
+      schema: { value: Schema.String },
+    })
+    const payload: typeof definition.Type = {
+      id: Event.ID.create(),
+      type: definition.type,
+      data: { value: "value" },
+    }
+
+    expect(Schema.is(definition)(payload)).toBe(true)
+    expect(
+      Schema.is(definition)({
+        ...payload,
+        durable: { aggregateID: "aggregate", seq: 0, version: 1 },
+      }),
+    ).toBe(false)
+
+    const invalid: typeof definition.Type = {
+      ...payload,
+      // @ts-expect-error Live payloads cannot carry durable commit metadata.
+      durable: { aggregateID: "aggregate", seq: 0, version: 1 },
+    }
+    void invalid
+  })
+
+  test("mixed definition payloads preserve durability correlation", () => {
+    const durable = Event.define({
+      type: "test.mixed.durable",
+      durable: { aggregate: "id", version: 2 },
+      schema: { id: Schema.String },
+    })
+    const live = Event.define({
+      type: "test.mixed.live",
+      schema: { value: Schema.String },
+    })
+    type Mixed = Event.Payload<typeof durable | typeof live>
+
+    const committed: Mixed = {
+      id: Event.ID.create(),
+      type: durable.type,
+      durable: { aggregateID: "aggregate", seq: 0, version: 2 },
+      data: { id: "aggregate" },
+    }
+    const ephemeral: Mixed = {
+      id: Event.ID.create(),
+      type: live.type,
+      data: { value: "value" },
+    }
+    void committed
+    void ephemeral
+
+    // @ts-expect-error Durable union members require commit metadata.
+    const uncommitted: Mixed = { id: Event.ID.create(), type: durable.type, data: { id: "aggregate" } }
+    // @ts-expect-error Live union members cannot carry durable commit metadata.
+    const falselyCommitted: Mixed = {
+      id: Event.ID.create(),
+      type: live.type,
+      durable: { aggregateID: "aggregate", seq: 0, version: 2 },
+      data: { value: "value" },
+    }
+    void uncommitted
+    void falselyCommitted
+  })
 })

packages/sdk/js/script/build.ts

@@ -58,6 +58,17 @@ if (sseTypesPatched === sseTypesSource) {
 }
 await Bun.write(sseTypesPath, sseTypesPatched)
 
+// OpenAPI represents Schema.Never as `not: {}`, which @hey-api currently
+// widens to unknown. Preserve impossible optional event fields as never.
+const eventTypesPath = "./src/v2/gen/types.gen.ts"
+const eventTypesFile = Bun.file(eventTypesPath)
+const eventTypesSource = await eventTypesFile.text()
+const eventTypesPatched = eventTypesSource.replaceAll("  durable?: unknown", "  durable?: never")
+if (eventTypesPatched === eventTypesSource) {
+  throw new Error(`Event never patch did not apply; @hey-api/openapi-ts output may have changed (${eventTypesPath})`)
+}
+await Bun.write(eventTypesPath, eventTypesPatched)
+
 await $`bun prettier --write src/gen`
 await $`bun prettier --write src/v2`
 await $`rm -rf dist`

specs/v2/instructions.md

@@ -92,7 +92,7 @@ Use Effect schemas as the public contract:
 - branded schemas for ids
 - `Schema.Class` or `Schema.Struct` for domain data
 - `Schema.TaggedErrorClass` for expected errors
-- existing core helpers like `DeepMutable`, `withStatics`, and integer schemas where appropriate
+- existing core helpers like `DeepMutable`, `statics`, and integer schemas where appropriate
 
 Prefer `Info` objects as the stored domain records. Add static `empty(...)` constructors when update APIs need to create records on first mutation.
 

specs/v2/provider-model.md

@@ -5,7 +5,7 @@
 ```ts
 export const ID = Schema.String.pipe(
   Schema.brand("ProviderV2.ID"),
-  withStatics((schema) => ({
+  statics((schema) => ({
     opencode: schema.make("opencode"),
     anthropic: schema.make("anthropic"),
     openai: schema.make("openai"),