NotePlan MCP Server

Implementation Reference

• src/index.ts:133-155 (registration)

  Registers the MCP tool 'update_note' with Zod input schema (id required, title/content optional) and handler function that constructs updates object and calls noteService.updateNote, returning JSON stringified response.

  server.tool(
    'update_note',
    {
      id: z.string().describe('The ID of the note to update'),
      title: z.string().optional().describe('New title for the note'),
      content: z.string().optional().describe('New content for the note'),
    },
    async ({ id, title, content }) => {
      const updates: any = {};
      if (title !== undefined) updates.title = title;
      if (content !== undefined) updates.content = content;
      
      const updatedNote = noteService.updateNote(id, updates);
      return {
        content: [
          {
            type: 'text',
            text: JSON.stringify(updatedNote, null, 2),
          },
        ],
      };
    }
  );

• src/services/noteService.ts:370-435 (handler)

  Core handler function that performs the actual note update: retrieves note by ID, updates markdown file content (handling title header specially) if NotePlan available, or updates mock database otherwise, then returns the updated note object.

  function updateNote(id: string, updates: UpdateNoteParams): Note {
    const existingNote = getNoteById(id);
    if (!existingNote) {
      throw new Error(`Note with id ${id} not found`);
    }
    
    if (isNotePlanAvailable() && existingNote.filePath) {
      try {
        // Update the file content
        let newContent = existingNote.content;
        
        if (updates.content !== undefined) {
          newContent = updates.content;
        }
        
        // If title is being updated, update the first markdown header
        if (updates.title !== undefined) {
          const lines = newContent.split('\n');
          let headerUpdated = false;
          
          for (let i = 0; i < lines.length; i++) {
            if (lines[i].startsWith('# ')) {
              lines[i] = `# ${updates.title}`;
              headerUpdated = true;
              break;
            }
          }
          
          // If no header found, add one at the beginning
          if (!headerUpdated) {
            lines.unshift(`# ${updates.title}`, '');
          }
          
          newContent = lines.join('\n');
        }
        
        // Write updated content to file
        fs.writeFileSync(existingNote.filePath, newContent, 'utf8');
        
        // Clear cache to force refresh
        notesCache = [];
        lastCacheUpdate = 0;
        
        // Return updated note
        return parseMarkdownFile(existingNote.filePath, existingNote.folder)!;
      } catch (error) {
        throw new Error(`Failed to update note: ${(error as Error).message}`);
      }
    } else {
      // Fallback to mock database
      const noteIndex = notesDb.findIndex(note => note.id === id);
      if (noteIndex === -1) {
        throw new Error(`Note with id ${id} not found`);
      }
      
      const note = notesDb[noteIndex];
      const updatedNote: Note = {
        ...note,
        ...updates,
        modified: new Date().toISOString()
      };
      
      notesDb[noteIndex] = updatedNote;
      return updatedNote;
    }
  }

• src/services/noteService.ts:32-36 (schema)

  TypeScript interface defining optional parameters for note updates (title, content, folder).

  interface UpdateNoteParams {
    title?: string;
    content?: string;
    folder?: string;
  }

• src/index.ts:136-139 (schema)

  Zod schema for 'update_note' tool input validation in MCP registration (id required, title and content optional with descriptions).

    id: z.string().describe('The ID of the note to update'),
    title: z.string().optional().describe('New title for the note'),
    content: z.string().optional().describe('New content for the note'),
  },

• src/services/noteService.ts:437-444 (helper)

  Exports the noteService object including the updateNote function for use by MCP handlers.

  export const noteService = {
    getAllNotes,
    getNoteById,
    searchNotes,
    getNotesByFolder,
    createDailyNote,
    createNote,
    updateNote