Logseq MCP Server

Instructions

Implementation Reference

• src/graph.ts:333-408 (handler)

  Core handler implementing getGraph tool logic: builds graph nodes (pages, journals, tags) and edges (links, backlinks, tags) from page metadata, with optional center node BFS traversal limited by depth.

  async getGraph(options?: { center?: string; depth?: number }): Promise<Graph> {
    const nodes: GraphNode[] = [];
    const edges: GraphEdge[] = [];
    const nodeSet = new Set<string>();
    const pages = await this.listPages();
  
    const addNode = (id: string, name: string, type: GraphNode['type']) => {
      if (!nodeSet.has(id)) {
        nodeSet.add(id);
        nodes.push({ id, name, type });
      }
    };
  
    if (options?.center) {
      // Build graph around center node
      const visited = new Set<string>();
      const queue: { name: string; depth: number }[] = [{ name: options.center, depth: 0 }];
      // 보안: depth는 0 이상, MAX_DEPTH 이하로 제한
      const requestedDepth = options.depth ?? 1;
      const maxDepth = Math.max(0, Math.min(requestedDepth, MAX_DEPTH));
  
      while (queue.length > 0) {
        const { name, depth } = queue.shift()!;
        if (visited.has(name) || depth > maxDepth) continue;
        visited.add(name);
  
        const page = pages.find(p => p.name === name);
        if (!page) continue;
  
        const nodeType = page.isJournal ? 'journal' : 'page';
        addNode(name, name, nodeType);
  
        // Add links
        for (const link of page.links) {
          addNode(link, link, 'page');
          edges.push({ source: name, target: link, type: 'link' });
          if (depth < maxDepth) {
            queue.push({ name: link, depth: depth + 1 });
          }
        }
  
        // Add backlinks
        for (const backlink of page.backlinks) {
          addNode(backlink, backlink, 'page');
          edges.push({ source: backlink, target: name, type: 'backlink' });
          if (depth < maxDepth) {
            queue.push({ name: backlink, depth: depth + 1 });
          }
        }
  
        // Add tags
        for (const tag of page.tags) {
          addNode(`tag:${tag}`, tag, 'tag');
          edges.push({ source: name, target: `tag:${tag}`, type: 'tag' });
        }
      }
    } else {
      // Full graph
      for (const page of pages) {
        const nodeType = page.isJournal ? 'journal' : 'page';
        addNode(page.name, page.name, nodeType);
  
        for (const link of page.links) {
          addNode(link, link, 'page');
          edges.push({ source: page.name, target: link, type: 'link' });
        }
  
        for (const tag of page.tags) {
          addNode(`tag:${tag}`, tag, 'tag');
          edges.push({ source: page.name, target: `tag:${tag}`, type: 'tag' });
        }
      }
    }
  
    return { nodes, edges };
  }

• src/index.ts:95-98 (schema)

  Input schema validation using Zod for get_graph tool parameters: center (optional page name), depth (optional integer 0-10).

  const GetGraphSchema = z.object({
    center: z.string().max(MAX_NAME_LENGTH).optional().describe('중심 페이지 이름 (선택)'),
    depth: z.number().int().min(0).max(10).optional().describe('탐색 깊이 (기본값: 1, 최대: 10)'),
  });

• src/index.ts:205-215 (registration)

  MCP tool registration in server's TOOLS array defining get_graph with name, description, and inputSchema.

  {
    name: 'get_graph',
    description: '페이지 간 연결 그래프 데이터 조회. 링크/백링크/태그 관계 포함',
    inputSchema: {
      type: 'object' as const,
      properties: {
        center: { type: 'string', description: '중심 페이지 이름 (선택)' },
        depth: { type: 'number', description: '탐색 깊이 (기본값: 1)' },
      },
    },
  },

• src/index.ts:314-320 (handler)

  MCP CallToolRequestSchema handler case for get_graph: parses input, invokes GraphService.getGraph, returns JSON stringified response.

  case 'get_graph': {
    const { center, depth } = GetGraphSchema.parse(args);
    const graphData = await graph.getGraph({ center, depth });
    return {
      content: [{ type: 'text', text: JSON.stringify(graphData, null, 2) }],
    };
  }

• src/types.ts:45-60 (schema)

  TypeScript interfaces defining output schema for get_graph: GraphNode, GraphEdge, and Graph structures.

  export interface GraphNode {
    id: string;
    name: string;
    type: 'page' | 'tag' | 'journal';
  }
  
  export interface GraphEdge {
    source: string;
    target: string;
    type: 'link' | 'tag' | 'backlink';
  }
  
  export interface Graph {
    nodes: GraphNode[];
    edges: GraphEdge[];
  }