fix(tui): scope prompt history by session

packages/tui/src/component/prompt/index.tsx

@@ -977,7 +977,7 @@ export function Prompt(props: PromptProps) {
               return
             }
 
-            const item = history.move(-1, input.plainText)
+            const item = history.move(props.sessionID, -1, input.plainText)
             if (!item) return false
             input.setText(item.text)
             setStore("prompt", item)
@@ -1016,7 +1016,7 @@ export function Prompt(props: PromptProps) {
               return
             }
 
-            const item = history.move(1, input.plainText)
+            const item = history.move(props.sessionID, 1, input.plainText)
             if (!item) return false
             input.setText(item.text)
             setStore("prompt", item)
@@ -1288,7 +1288,7 @@ export function Prompt(props: PromptProps) {
         })
       if (pendingEditorSelection) editor.markSelectionSent()
     }
-    history.append({
+    history.append(sessionID, {
       ...store.prompt,
       mode: currentMode,
     })
@@ -1463,7 +1463,7 @@ export function Prompt(props: PromptProps) {
       (store.prompt.files?.length ?? 0) > 0 ||
       (store.prompt.agents?.length ?? 0) > 0
     ) {
-      history.append({
+      history.append(props.sessionID, {
         ...store.prompt,
         mode: store.mode,
       })

packages/tui/src/prompt/history.tsx

@@ -26,6 +26,11 @@ export type PromptPartRef = {
   index: number
 }
 
+type PromptHistoryEntry = {
+  sessionID: string | undefined
+  prompt: PromptInfo
+}
+
 export const emptyPrompt = (): PromptInfo => ({ text: "", files: [], agents: [], skills: [], pasted: [] })
 
 export const MAX_HISTORY_ENTRIES = 50
@@ -36,12 +41,19 @@ export function parsePromptHistory(text: string) {
     .filter(Boolean)
     .map((line) => {
       try {
-        return parsePromptInfo(JSON.parse(line))
+        const value: unknown = JSON.parse(line)
+        const input = value && typeof value === "object" ? (value as Record<string, unknown>) : undefined
+        const prompt = parsePromptInfo(input?.prompt ?? value)
+        if (!prompt) return
+        return {
+          sessionID: typeof input?.sessionID === "string" ? input.sessionID : undefined,
+          prompt,
+        }
       } catch {
         return undefined
       }
     })
-    .filter((line): line is PromptInfo => line !== undefined)
+    .filter((line): line is PromptHistoryEntry => line !== undefined)
     .slice(-MAX_HISTORY_ENTRIES)
 }
 
@@ -72,26 +84,29 @@ export const { use: usePromptHistory, provider: PromptHistoryProvider } = create
     })
 
     const [store, setStore] = createStore({
-      index: 0,
-      history: [] as PromptInfo[],
+      history: [] as PromptHistoryEntry[],
     })
+    const indices = new Map<string | undefined, number>()
 
     return {
-      move(direction: 1 | -1, input: string) {
-        if (!store.history.length) return undefined
-        const current = store.history.at(store.index)
+      move(sessionID: string | undefined, direction: 1 | -1, input: string) {
+        const items = store.history.filter((entry) => entry.sessionID === sessionID)
+        if (!items.length) return undefined
+        const index = indices.get(sessionID) ?? 0
+        const current = items.at(index)?.prompt
         if (!current) return undefined
         if (current.text !== input && input.length) return
-        const next = store.index + direction
-        if (Math.abs(next) > store.history.length || next > 0) return
-        setStore("index", next)
+        const next = index + direction
+        if (Math.abs(next) > items.length || next > 0) return
+        indices.set(sessionID, next)
         if (next === 0) return emptyPrompt()
-        return store.history.at(next)
+        return items.at(next)?.prompt
       },
-      append(item: PromptInfo) {
-        const entry = structuredClone(unwrap(item))
-        if (isDuplicateEntry(store.history.at(-1), entry)) {
-          setStore("index", 0)
+      append(sessionID: string | undefined, item: PromptInfo) {
+        const entry = { sessionID, prompt: structuredClone(unwrap(item)) }
+        const previous = store.history.findLast((item) => item.sessionID === sessionID)
+        if (isDuplicateEntry(previous?.prompt, entry.prompt)) {
+          indices.set(sessionID, 0)
           return
         }
         let trimmed = false
@@ -102,9 +117,9 @@ export const { use: usePromptHistory, provider: PromptHistoryProvider } = create
               draft.history = draft.history.slice(-MAX_HISTORY_ENTRIES)
               trimmed = true
             }
-            draft.index = 0
           }),
         )
+        indices.set(sessionID, 0)
 
         if (trimmed) {
           writeText(historyPath, store.history.map((line) => JSON.stringify(line)).join("\n") + "\n").catch(() => {})

packages/tui/test/prompt/history-provider.test.tsx

@@ -27,11 +27,41 @@ test("down rejects at the newest history item with an empty prompt", async () =>
   ))
   try {
     await app.renderOnce()
-    history!.append({ text: "previous", files: [], agents: [], pasted: [] })
+    history!.append("session-a", { text: "previous", files: [], agents: [], pasted: [] })
 
-    expect(history!.move(1, "")).toBeUndefined()
-    expect(history!.move(-1, "")?.text).toBe("previous")
-    expect(history!.move(1, "previous")?.text).toBe("")
+    expect(history!.move("session-a", 1, "")).toBeUndefined()
+    expect(history!.move("session-a", -1, "")?.text).toBe("previous")
+    expect(history!.move("session-a", 1, "previous")?.text).toBe("")
+  } finally {
+    app.renderer.destroy()
+  }
+})
+
+test("scopes prompt history to the current session", async () => {
+  await using tmp = await tmpdir()
+  const state = path.join(tmp.path, "state")
+  await mkdir(state, { recursive: true })
+  let history: ReturnType<typeof usePromptHistory>
+
+  function Consumer() {
+    history = usePromptHistory()
+    return <box />
+  }
+
+  const app = await testRender(() => (
+    <TuiPathsProvider value={{ cwd: tmp.path, home: tmp.path, state, worktree: tmp.path }}>
+      <PromptHistoryProvider>
+        <Consumer />
+      </PromptHistoryProvider>
+    </TuiPathsProvider>
+  ))
+  try {
+    await app.renderOnce()
+    history!.append("session-a", { text: "from a", files: [], agents: [], pasted: [] })
+    history!.append("session-b", { text: "from b", files: [], agents: [], pasted: [] })
+
+    expect(history!.move("session-a", -1, "")?.text).toBe("from a")
+    expect(history!.move("session-b", -1, "")?.text).toBe("from b")
   } finally {
     app.renderer.destroy()
   }

packages/tui/test/prompt/history.test.ts

@@ -11,8 +11,8 @@ const entry = (text: string, files: PromptInfo["files"] = []): PromptInfo => ({
 describe("prompt history", () => {
   test("recovers valid JSONL entries around corruption", () => {
     expect(parsePromptHistory(`${JSON.stringify(entry("one"))}\nnot-json\n${JSON.stringify(entry("two"))}\n`)).toEqual([
-      entry("one"),
-      entry("two"),
+      { sessionID: undefined, prompt: entry("one") },
+      { sessionID: undefined, prompt: entry("two") },
     ])
   })
 
@@ -26,7 +26,7 @@ describe("prompt history", () => {
     ).join("\n")
     const result = parsePromptHistory(input)
     expect(result).toHaveLength(MAX_HISTORY_ENTRIES)
-    expect(result[0]?.text).toBe("5")
+    expect(result[0]?.prompt.text).toBe("5")
   })
 
   test("dedupes only identical consecutive entries", () => {
@@ -56,6 +56,11 @@ describe("prompt history", () => {
       },
     ])
 
+    expect(parsePromptHistory(JSON.stringify(value))).toEqual([{ sessionID: undefined, prompt: value }])
+  })
+
+  test("preserves the session scope", () => {
+    const value = { sessionID: "session-a", prompt: entry("hello") }
     expect(parsePromptHistory(JSON.stringify(value))).toEqual([value])
   })
 })