update_obsidian_note

Instructions

Implementation Reference

• src/tools/notes.ts:201-260 (handler)

  Core handler method `updateNote()` that executes the update logic for an Obsidian note. It checks file existence, optionally creates a backup, reads existing content, applies the update mode (replace/append/prepend), updates frontmatter with a new modified timestamp, and writes back to disk.

  async updateNote(
    path: string,
    newContent: string,
    mode: 'replace' | 'append' | 'prepend' = 'replace',
    createBackup: boolean = true
  ): Promise<NoteMetadata> {
    try {
      // ファイルの存在確認
      if (!(await this.fileSystem.exists(path))) {
        throw new Error(`${ErrorCode.FILE_NOT_FOUND}: File '${path}' not found`);
      }
  
      // バックアップを作成
      if (createBackup) {
        await this.fileSystem.createBackup(path);
      }
  
      // 既存のコンテンツを読み取り
      const { content: existingContent, frontmatter } = await this.readNote(path);
  
      // 更新モードに応じてコンテンツを結合
      let finalContent: string;
      switch (mode) {
        case 'replace':
          finalContent = newContent;
          break;
        case 'append':
          finalContent = existingContent + '\\n\\n' + newContent;
          break;
        case 'prepend':
          finalContent = newContent + '\\n\\n' + existingContent;
          break;
        default:
          throw new Error(`${ErrorCode.TRANSLATION_FAILED}: Invalid mode '${mode}'`);
      }
  
      // Frontmatterを更新
      const updatedFrontmatter = {
        ...frontmatter,
        modified: new Date().toISOString()
      };
  
      // ファイルを更新
      const noteContent = matter.stringify(finalContent, updatedFrontmatter);
      await this.fileSystem.writeFile(path, noteContent);
  
      return {
        title: frontmatter.title || path.split('/').pop()?.replace('.md', '') || 'Untitled',
        path,
        tags: frontmatter.tags || [],
        lastModified: new Date(),
        created: new Date(frontmatter.created || new Date())
      };
    } catch (error) {
      if (error instanceof Error) {
        throw error;
      }
      throw new Error(`${ErrorCode.PERMISSION_DENIED}: Failed to update note '${path}'`);
    }
  }

• src/index.ts:230-251 (handler)

  MCP request handler `handleUpdateNote()` that extracts path, content, mode, and createBackup from `args` and delegates to `notesTool.updateNote()`. It validates required parameters and formats the success response.

  private async handleUpdateNote(args: any) {
    const { path, content, mode, createBackup } = args;
    
    if (!path || !content) {
      throw new McpError(ErrorCode.InvalidParams, 'Path and content are required');
    }
  
    const result = await this.notesTool.updateNote(path, content, mode, createBackup);
  
    return {
      content: [
        {
          type: 'text',
          text: `✅ ノートが更新されました\\n\\n` +
                `📁 パス: ${result.path}\\n` +
                `📝 タイトル: ${result.title}\\n` +
                `🔄 更新モード: ${mode || 'replace'}\\n` +
                `⏰ 更新日時: ${result.lastModified.toISOString()}`
        }
      ]
    };
  }

• src/tools/notes.ts:74-103 (schema)

  Tool definition `getUpdateNoteToolDefinition()` returning the schema for 'update_obsidian_note': defines input properties (path, content, mode with enum replace/append/prepend, createBackup) with required fields path and content.

  static getUpdateNoteToolDefinition(): Tool {
    return {
      name: 'update_obsidian_note',
      description: 'Update an existing Obsidian note',
      inputSchema: {
        type: 'object',
        properties: {
          path: {
            type: 'string',
            description: 'Path to the note (relative to vault root)'
          },
          content: {
            type: 'string',
            description: 'New content for the note'
          },
          mode: {
            type: 'string',
            enum: ['replace', 'append', 'prepend'],
            description: 'Update mode: replace, append, or prepend content',
            default: 'replace'
          },
          createBackup: {
            type: 'boolean',
            description: 'Whether to create a backup before updating',
            default: true
          }
        },
        required: ['path', 'content']
      }
    };

• src/index.ts:89-98 (registration)

  Tool registration in `ListToolsRequestSchema` handler: the 'update_obsidian_note' tool is listed via `NotesTool.getUpdateNoteToolDefinition()` on line 95, making it available to clients.

  this.server.setRequestHandler(ListToolsRequestSchema, async () => {
    return {
      tools: [
        TranslateTool.getToolDefinition(),
        NotesTool.getCreateNoteToolDefinition(),
        NotesTool.getReadNoteToolDefinition(),
        NotesTool.getUpdateNoteToolDefinition(),
        SearchTool.getSearchToolDefinition(),
        SearchTool.getSearchByTagsToolDefinition(),
      ],

• src/index.ts:117-118 (registration)

  Tool dispatch in `CallToolRequestSchema` handler: the switch-case on line 117 routes the name 'update_obsidian_note' to `handleUpdateNote()`.

  case 'update_obsidian_note':
    return await this.handleUpdateNote(args);