fix(core): include full filePath alongside fileName in edit/write-file diff results

packages/acp-bridge/src/transcript-replay.test.ts

@@ -450,6 +450,60 @@ describe('createTranscriptReplayMachine', () => {
     expect(machine.snapshot().pendingToolCalls).toEqual([]);
   });
 
+  it('prefers filePath over the fileName basename when replaying an edit diff', () => {
+    const machine = createTranscriptReplayMachine();
+    updates(
+      machine,
+      record('assistant-1', 'assistant', {
+        message: {
+          role: 'model',
+          parts: [
+            { functionCall: { name: 'edit_file', args: {}, id: 'call-1' } },
+          ],
+        },
+      }),
+    );
+    const result = updates(
+      machine,
+      record('result-1', 'tool_result', {
+        message: {
+          role: 'user',
+          parts: [
+            {
+              functionResponse: {
+                name: 'edit_file',
+                response: { output: 'edited' },
+              },
+            },
+          ],
+        },
+        toolCallResult: {
+          callId: 'call-1',
+          resultDisplay: {
+            fileDiff: '--- a\n+++ b\n',
+            fileName: 'Foo.kt',
+            filePath: '/workspace/app/src/main/java/com/example/Foo.kt',
+            originalContent: 'old',
+            newContent: 'new',
+          },
+        },
+      }),
+    );
+
+    expect(result[0]).toMatchObject({
+      sessionUpdate: 'tool_call_update',
+      toolCallId: 'call-1',
+      content: [
+        {
+          type: 'diff',
+          path: '/workspace/app/src/main/java/com/example/Foo.kt',
+          oldText: 'old',
+          newText: 'new',
+        },
+      ],
+    });
+  });
+
   it('reports ambiguous same-name result correlation', () => {
     const onDiagnostic = vi.fn();
     const machine = createTranscriptReplayMachine({ onDiagnostic });

packages/acp-bridge/src/transcript-replay.ts

@@ -1304,9 +1304,11 @@ function extractDiffContent(resultDisplay: unknown): ToolCallContent | null {
   return {
     type: 'diff',
     path:
-      typeof resultDisplay['fileName'] === 'string'
-        ? resultDisplay['fileName']
-        : '',
+      typeof resultDisplay['filePath'] === 'string'
+        ? resultDisplay['filePath']
+        : typeof resultDisplay['fileName'] === 'string'
+          ? resultDisplay['fileName']
+          : '',
     oldText:
       typeof resultDisplay['originalContent'] === 'string'
         ? resultDisplay['originalContent']

packages/cli/src/ui/utils/export/normalize.test.ts

@@ -71,6 +71,59 @@ describe('normalizeSessionData', () => {
     ]);
   });
 
+  it('exports the diff path from filePath rather than the fileName basename', () => {
+    const record: ChatRecord = {
+      uuid: 'tool-2',
+      parentUuid: null,
+      sessionId: 'session-1',
+      timestamp: '2025-01-01T00:00:00.000Z',
+      type: 'tool_result',
+      cwd: '',
+      version: '1.0.0',
+      message: {
+        role: 'user',
+        parts: [
+          {
+            functionResponse: {
+              id: 'call-2',
+              name: 'edit_file',
+              response: { output: 'ok' },
+            },
+          },
+        ],
+      },
+      toolCallResult: {
+        callId: 'call-2',
+        resultDisplay: {
+          fileName: 'Foo.kt',
+          filePath: '/workspace/app/src/main/java/com/example/Foo.kt',
+          fileDiff: '--- Foo.kt\n+++ Foo.kt\n',
+          originalContent: 'old',
+          newContent: 'new',
+        },
+      },
+    };
+
+    const normalized = normalizeSessionData(
+      {
+        sessionId: 'session-1',
+        startTime: '2025-01-01T00:00:00.000Z',
+        messages: [],
+      },
+      [record],
+      config,
+    );
+
+    expect(normalized.messages[0].toolCall?.content).toEqual([
+      {
+        type: 'diff',
+        path: '/workspace/app/src/main/java/com/example/Foo.kt',
+        oldText: 'old',
+        newText: 'new',
+      },
+    ]);
+  });
+
   it('accepts the minimal daemon export config shape', () => {
     const minimalConfig: ExportConfig = {};
     const record: ChatRecord = {

packages/cli/src/ui/utils/export/normalize.ts

@@ -327,7 +327,10 @@ function extractDiffContent(
     return [
       {
         type: 'diff',
-        path: display['fileName'] as string,
+        path:
+          typeof display['filePath'] === 'string'
+            ? display['filePath']
+            : (display['fileName'] as string),
         oldText: (display['originalContent'] as string) ?? '',
         newText: display['newContent'] as string,
       },

packages/core/src/tools/edit.test.ts

@@ -603,6 +603,10 @@ describe('EditTool', () => {
       expect(display.fileDiff).toMatch(initialContent);
       expect(display.fileDiff).toMatch(newContent);
       expect(display.fileName).toBe(testFile);
+      // `filePath` must carry the full path: UI consumers (e.g. the VSCode
+      // companion) cannot resolve a clickable location from `fileName`
+      // alone once the file is outside the workspace root.
+      expect(display.filePath).toBe(filePath);
     });
 
     // trackEdit is best-effort: a FileHistoryService failure (disk full,

packages/core/src/tools/edit.ts

@@ -7,6 +7,7 @@
 import * as fs from 'node:fs';
 import * as path from 'node:path';
 import type {
+  FileDiff,
   ToolCallConfirmationDetails,
   ToolEditConfirmationDetails,
   ToolInvocation,
@@ -672,9 +673,10 @@ class EditToolInvocation implements ToolInvocation<EditToolParams, ToolResult> {
         'Current',
         'Proposed',
       );
-      const displayResult = {
+      const displayResult: FileDiff = {
         fileDiff,
         fileName,
+        filePath: this.params.file_path,
         originalContent: editData.currentContent,
         newContent: editData.newContent,
         diffStat,

packages/core/src/tools/tools.ts

@@ -774,6 +774,13 @@ export interface TaskListResultDisplay {
 export interface FileDiff {
   fileDiff: string;
   fileName: string;
+  /**
+   * Full (project-relative or absolute) path to the edited file, as passed
+   * to the tool. UI consumers must prefer this over `fileName` when
+   * resolving a clickable/openable location — `fileName` is a basename and
+   * cannot be used to locate files outside the workspace root.
+   */
+  filePath?: string;
   originalContent: string | null;
   newContent: string;
   diffStat?: DiffStat;

packages/core/src/tools/write-file.test.ts

@@ -464,6 +464,7 @@ describe('WriteFileTool', () => {
       expect(writtenContent).toBe(proposedContent);
       const display = result.returnDisplay as FileDiff;
       expect(display.fileName).toBe('execute_new_file.txt');
+      expect(display.filePath).toBe(filePath);
       expect(display.fileDiff).toMatch(/--- execute_new_file.txt\tOriginal/);
       expect(display.fileDiff).toMatch(/\+\+\+ execute_new_file.txt\tWritten/);
       expect(display.fileDiff).toMatch(
@@ -824,6 +825,7 @@ describe('WriteFileTool', () => {
       expect(writtenContent).toBe(proposedContent);
       const display = result.returnDisplay as FileDiff;
       expect(display.fileName).toBe('execute_existing_file.txt');
+      expect(display.filePath).toBe(filePath);
       expect(display.fileDiff).toMatch(
         initialContent.replace(/[.*+?^${}()|[\\]\\]/g, '\\$&'),
       );

packages/core/src/tools/write-file.ts

@@ -611,6 +611,7 @@ class WriteFileToolInvocation extends BaseToolInvocation<
       const displayResult: FileDiff = {
         fileDiff,
         fileName,
+        filePath: file_path,
         originalContent,
         newContent: content,
         diffStat,