ExecutionMetadataからProject Rootを削除

worktreeモードでタスク実行時、エージェントがmainディレクトリで
作業してしまうバグの修正。metadataでProject Rootを見せていたため
Claudeがそちらで作業していた可能性がある。

- ExecutionMetadataインターフェースからprojectRootを削除
- buildExecutionMetadataからprojectRoot設定を削除
- METADATA_STRINGSからprojectRootとmodeを削除
- renderExecutionMetadataからProject Root表示を削除
- 関連テストを更新

src/__tests__/instructionBuilder.test.ts

@@ -47,7 +47,7 @@ describe('instruction-builder', () => {
       expect(result).toContain('Do some work');
     });
 
-    it('should include Project Root and Mode when cwd !== projectCwd', () => {
+    it('should NOT include Project Root even when cwd !== projectCwd', () => {
       const step = createMinimalStep('Do some work');
       const context = createMinimalContext({
         cwd: '/worktree-path',
@@ -58,36 +58,11 @@ describe('instruction-builder', () => {
 
       expect(result).toContain('## Execution Context');
       expect(result).toContain('Working Directory: /worktree-path');
-      expect(result).toContain('Project Root: /project-path');
+      expect(result).not.toContain('Project Root');
-      expect(result).toContain('Mode: worktree');
+      expect(result).not.toContain('Mode:');
       expect(result).toContain('Do some work');
     });
 
-    it('should NOT include Project Root or Mode when cwd === projectCwd', () => {
-      const step = createMinimalStep('Do some work');
-      const context = createMinimalContext({
-        cwd: '/project',
-        projectCwd: '/project',
-      });
-
-      const result = buildInstruction(step, context);
-
-      expect(result).toContain('Working Directory: /project');
-      expect(result).not.toContain('Project Root');
-      expect(result).not.toContain('Mode:');
-    });
-
-    it('should NOT include Project Root or Mode when projectCwd is not set', () => {
-      const step = createMinimalStep('Do some work');
-      const context = createMinimalContext({ cwd: '/project' });
-
-      const result = buildInstruction(step, context);
-
-      expect(result).toContain('Working Directory: /project');
-      expect(result).not.toContain('Project Root');
-      expect(result).not.toContain('Mode:');
-    });
-
     it('should prepend metadata before the instruction body', () => {
       const step = createMinimalStep('Do some work');
       const context = createMinimalContext({ cwd: '/project' });
@@ -133,7 +108,8 @@ describe('instruction-builder', () => {
         '- Report: /project/.takt/reports/20260128-worktree-report/00-plan.md'
       );
       expect(result).toContain('Working Directory: /project/.takt/worktrees/my-task');
-      expect(result).toContain('Project Root: /project');
+      // Project Root should NOT be included in metadata (to avoid agent confusion)
+      expect(result).not.toContain('Project Root');
     });
 
     it('should replace multiple .takt/reports/{report_dir} occurrences', () => {
@@ -183,15 +159,14 @@ describe('instruction-builder', () => {
   });
 
   describe('buildExecutionMetadata', () => {
-    it('should set workingDirectory and omit projectRoot in normal mode', () => {
+    it('should set workingDirectory', () => {
       const context = createMinimalContext({ cwd: '/project' });
       const metadata = buildExecutionMetadata(context);
 
       expect(metadata.workingDirectory).toBe('/project');
-      expect(metadata.projectRoot).toBeUndefined();
     });
 
-    it('should set projectRoot in worktree mode', () => {
+    it('should use cwd as workingDirectory even in worktree mode', () => {
       const context = createMinimalContext({
         cwd: '/worktree-path',
         projectCwd: '/project-path',
@@ -199,27 +174,6 @@ describe('instruction-builder', () => {
       const metadata = buildExecutionMetadata(context);
 
       expect(metadata.workingDirectory).toBe('/worktree-path');
-      expect(metadata.projectRoot).toBe('/project-path');
-    });
-
-    it('should omit projectRoot when projectCwd is not set', () => {
-      const context = createMinimalContext({ cwd: '/project' });
-      // projectCwd is undefined by default
-      const metadata = buildExecutionMetadata(context);
-
-      expect(metadata.workingDirectory).toBe('/project');
-      expect(metadata.projectRoot).toBeUndefined();
-    });
-
-    it('should omit projectRoot when cwd equals projectCwd', () => {
-      const context = createMinimalContext({
-        cwd: '/same-path',
-        projectCwd: '/same-path',
-      });
-      const metadata = buildExecutionMetadata(context);
-
-      expect(metadata.workingDirectory).toBe('/same-path');
-      expect(metadata.projectRoot).toBeUndefined();
     });
 
     it('should default language to en when not specified', () => {
@@ -238,7 +192,7 @@ describe('instruction-builder', () => {
   });
 
   describe('renderExecutionMetadata', () => {
-    it('should render normal mode without Project Root or Mode', () => {
+    it('should render Working Directory only', () => {
       const rendered = renderExecutionMetadata({ workingDirectory: '/project', language: 'en' });
 
       expect(rendered).toContain('## Execution Context');
@@ -247,19 +201,6 @@ describe('instruction-builder', () => {
       expect(rendered).not.toContain('Mode:');
     });
 
-    it('should render worktree mode with Project Root and Mode', () => {
-      const rendered = renderExecutionMetadata({
-        workingDirectory: '/worktree',
-        projectRoot: '/project',
-        language: 'en',
-      });
-
-      expect(rendered).toContain('## Execution Context');
-      expect(rendered).toContain('- Working Directory: /worktree');
-      expect(rendered).toContain('- Project Root: /project');
-      expect(rendered).toContain('- Mode: worktree');
-    });
-
     it('should end with a trailing empty line', () => {
       const rendered = renderExecutionMetadata({ workingDirectory: '/project', language: 'en' });
 
@@ -275,17 +216,6 @@ describe('instruction-builder', () => {
       expect(rendered).not.toContain('Working Directory');
     });
 
-    it('should render worktree mode in Japanese', () => {
-      const rendered = renderExecutionMetadata({
-        workingDirectory: '/worktree',
-        projectRoot: '/project',
-        language: 'ja',
-      });
-
-      expect(rendered).toContain('- プロジェクトルート: /project');
-      expect(rendered).toContain('モード: worktree');
-    });
-
     it('should include English note only for en, not for ja', () => {
       const enRendered = renderExecutionMetadata({ workingDirectory: '/project', language: 'en' });
       const jaRendered = renderExecutionMetadata({ workingDirectory: '/project', language: 'ja' });

src/workflow/instruction-builder.ts

@@ -39,8 +39,6 @@ export interface InstructionContext {
 export interface ExecutionMetadata {
   /** The agent's working directory (may be a worktree) */
   readonly workingDirectory: string;
-  /** Project root where .takt/ lives. Present only in worktree mode. */
-  readonly projectRoot?: string;
   /** Language for metadata rendering */
   readonly language: Language;
 }
@@ -49,15 +47,10 @@ export interface ExecutionMetadata {
  * Build execution metadata from instruction context.
  *
  * Pure function: InstructionContext → ExecutionMetadata.
- * Sets `projectRoot` only when cwd differs from projectCwd (worktree mode).
  */
 export function buildExecutionMetadata(context: InstructionContext): ExecutionMetadata {
-  const projectRoot = context.projectCwd ?? context.cwd;
-  const isWorktree = context.cwd !== projectRoot;
-
   return {
     workingDirectory: context.cwd,
-    ...(isWorktree ? { projectRoot } : {}),
     language: context.language ?? 'en',
   };
 }
@@ -67,15 +60,11 @@ const METADATA_STRINGS = {
   en: {
     heading: '## Execution Context',
     workingDirectory: 'Working Directory',
-    projectRoot: 'Project Root',
-    mode: 'Mode: worktree (source edits in Working Directory, reports in Project Root)',
     note: 'Note: This section is metadata. Follow the language used in the rest of the prompt.',
   },
   ja: {
     heading: '## 実行コンテキスト',
     workingDirectory: '作業ディレクトリ',
-    projectRoot: 'プロジェクトルート',
-    mode: 'モード: worktree（ソース編集は作業ディレクトリ、レポートはプロジェクトルート）',
     note: '',
   },
 } as const;
@@ -85,7 +74,6 @@ const METADATA_STRINGS = {
  *
  * Pure function: ExecutionMetadata → string.
  * Always includes heading + Working Directory.
- * Adds Project Root and Mode only in worktree mode (when projectRoot is present).
  * Language determines the output language; 'en' includes a note about language consistency.
  */
 export function renderExecutionMetadata(metadata: ExecutionMetadata): string {
@@ -94,10 +82,6 @@ export function renderExecutionMetadata(metadata: ExecutionMetadata): string {
     strings.heading,
     `- ${strings.workingDirectory}: ${metadata.workingDirectory}`,
   ];
-  if (metadata.projectRoot !== undefined) {
-    lines.push(`- ${strings.projectRoot}: ${metadata.projectRoot}`);
-    lines.push(`- ${strings.mode}`);
-  }
   if (strings.note) {
     lines.push('');
     lines.push(strings.note);