From 1faba03cfebbde40b2866d9ef2cc40d0e9cdf3a8 Mon Sep 17 00:00:00 2001
From: Aiden Cline <63023139+rekram1-node@users.noreply.github.com>
Date: Thu, 27 Aug 2026 21:36:22 -0500
Subject: [PATCH] fix(core): normalize Windows tool paths (#45806)

---
 packages/core/src/location-mutation.ts       | 16 +++++++++-------
 packages/core/src/tool/plugin/shell.ts       |  6 ++++--
 packages/core/test/location-mutation.test.ts | 15 ++++++++++++---
 3 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/packages/core/src/location-mutation.ts b/packages/core/src/location-mutation.ts
index 199d791db59..92f43f0e6f7 100644
--- a/packages/core/src/location-mutation.ts
+++ b/packages/core/src/location-mutation.ts
@@ -59,16 +59,18 @@ export interface Interface {
   readonly resolve: (input: ResolveInput) => Effect.Effect<Target, FSUtil.Error>
 }
 
-/** Lexical absolute path, expanding a leading `~` before resolving against `directory`. */
-export const resolvePath = (directory: string, input: string, home = Global.Path.home) =>
-  path.resolve(
+/** Lexical absolute path, normalizing Windows shell paths and expanding `~` before resolution. */
+export const resolvePath = (directory: string, input: string, home = Global.Path.home) => {
+  const normalized = FSUtil.windowsPath(input)
+  return path.resolve(
     directory,
-    input === "~"
+    normalized === "~"
       ? home
-      : input.startsWith("~/") || (process.platform === "win32" && input.startsWith("~\\"))
-        ? path.join(home, input.slice(2))
-        : input,
+      : normalized.startsWith("~/") || (process.platform === "win32" && normalized.startsWith("~\\"))
+        ? path.join(home, normalized.slice(2))
+        : normalized,
   )
+}
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/LocationMutation") {}
 
diff --git a/packages/core/src/tool/plugin/shell.ts b/packages/core/src/tool/plugin/shell.ts
index 37d869039bc..7409b6acd43 100644
--- a/packages/core/src/tool/plugin/shell.ts
+++ b/packages/core/src/tool/plugin/shell.ts
@@ -1,6 +1,5 @@
 export * as ShellTool from "./shell.js"
 
-import path from "path"
 import { ToolFailure } from "@opencode-ai/ai"
 import type { Context as PluginContext } from "@opencode-ai/plugin/effect/plugin"
 import { Deferred, Effect, Schema, Scope } from "effect"
@@ -190,7 +189,10 @@ export const Plugin = {
                       portable,
                     })
                     const directories = yield* Effect.forEach(parsed.directories, (directory) =>
-                      mutation.resolve({ path: path.resolve(target.absolute, directory), kind: "directory" }),
+                      mutation.resolve({
+                        path: LocationMutation.resolvePath(target.absolute, directory),
+                        kind: "directory",
+                      }),
                     )
                     const external = [target, ...directories]
                       .map((item) => item.externalDirectory)
diff --git a/packages/core/test/location-mutation.test.ts b/packages/core/test/location-mutation.test.ts
index a768158a1ad..461190f750b 100644
--- a/packages/core/test/location-mutation.test.ts
+++ b/packages/core/test/location-mutation.test.ts
@@ -236,9 +236,18 @@ describe("LocationMutation", () => {
     expect(LocationMutation.resolvePath("/project", "~/notes.md", home)).toBe(path.resolve(home, "notes.md"))
     expect(LocationMutation.resolvePath("/project", "~draft.md", home)).toBe(path.resolve("/project", "~draft.md"))
     expect(LocationMutation.resolvePath("/project", "~\\notes.md", home)).toBe(
-      process.platform === "win32"
-        ? path.resolve(home, "notes.md")
-        : path.resolve("/project", "~\\notes.md"),
+      process.platform === "win32" ? path.resolve(home, "notes.md") : path.resolve("/project", "~\\notes.md"),
+    )
+  })
+
+  test.each([
+    ["/c/Users/aiden/notes.md", "C:/Users/aiden/notes.md"],
+    ["/C:/Users/aiden/notes.md", "C:/Users/aiden/notes.md"],
+    ["/cygdrive/c/Users/aiden/notes.md", "C:/Users/aiden/notes.md"],
+    ["/mnt/c/Users/aiden/notes.md", "C:/Users/aiden/notes.md"],
+  ])("normalizes Windows shell drive path %s before resolution", (input, windows) => {
+    expect(LocationMutation.resolvePath("/project", input)).toBe(
+      process.platform === "win32" ? path.resolve(windows) : path.resolve(input),
     )
   })