ChainFETCH MCP Server

Instructions

Implementation Reference

• index.js:721-722 (handler)

  Handler implementation for the 'search_blocks_semantic' tool. It proxies the tool call to the ChainFETCH API endpoint '/api/v1/ethereum/blocks/semantic_search' using a GET request with the provided arguments.

  case 'search_blocks_semantic':
    return await this.makeRequest('/api/v1/ethereum/blocks/semantic_search', 'GET', args, null, token);

• index.js:272-286 (schema)

  Input schema definition for the 'search_blocks_semantic' tool, specifying required 'query' parameter and optional 'limit'.

  inputSchema: {
    type: 'object',
    properties: {
      query: {
        type: 'string',
        description: 'The query to search for',
      },
      limit: {
        type: 'integer',
        description: 'The number of results to return (default: 10)',
        default: 10,
      },
    },
    required: ['query'],
  },

• index.js:270-287 (registration)

  Registration of the 'search_blocks_semantic' tool in the MCP tools array passed to server.setTools().

    name: 'search_blocks_semantic',
    description: 'Semantic search for blocks using AI-powered vector similarity matching',
    inputSchema: {
      type: 'object',
      properties: {
        query: {
          type: 'string',
          description: 'The query to search for',
        },
        limit: {
          type: 'integer',
          description: 'The number of results to return (default: 10)',
          default: 10,
        },
      },
      required: ['query'],
    },
  },

• index.js:634-682 (helper)

  Helper function 'makeRequest' used by the handler to perform authenticated HTTP requests to the ChainFETCH API.

  async makeRequest(endpoint, method = 'GET', params = {}, body = null, token = null) {
    const chainfetchToken = token || process.env.CHAINFETCH_API_TOKEN;
    
    if (!chainfetchToken) {
      throw new McpError(
        ErrorCode.InvalidRequest,
        'CHAINFETCH_API_TOKEN is required'
      );
    }
  
    const url = new URL(`${API_BASE_URL}${endpoint}`);
    
    // Add query parameters for GET requests
    if (method === 'GET' && Object.keys(params).length > 0) {
      Object.entries(params).forEach(([key, value]) => {
        if (value !== undefined && value !== null) {
          if (Array.isArray(value)) {
            value.forEach(v => url.searchParams.append(`${key}[]`, v));
          } else {
            url.searchParams.append(key, value.toString());
          }
        }
      });
    }
  
    const fetchOptions = {
      method,
      headers: {
        'Authorization': `Bearer ${chainfetchToken}`,
        'Content-Type': 'application/json',
      },
    };
  
    if (body && method !== 'GET') {
      fetchOptions.body = JSON.stringify(body);
    }
  
    const response = await fetch(url.toString(), fetchOptions);
    
    if (!response.ok) {
      const errorText = await response.text();
      throw new McpError(
        ErrorCode.InternalError,
        `API request failed: ${response.status} ${response.statusText} - ${errorText}`
      );
    }
  
    return await response.json();
  }