AITable MCP Server

Instructions

Implementation Reference

• src/index.ts:182-213 (registration)

  Registration of the 'get_fields_schema' MCP tool, including description, input schema, and inline handler function that delegates to AitableService helpers.
  server.tool("get_fields_schema", "Returns the JSON schema of all fields within the specified database, This schema will be sent to LLM to help the AI understand the expected structure of the data.", { node_id: z.string().describe('The ID of the database to fetch records from.'), }, async ({ node_id }) => { try { if (!node_id) { throw new Error("The datasheet ID (node_id) is required."); } const result = await aitableService.getDatasheetFieldsSchema(node_id); if (!result.success) { throw new Error(result.message || "Failed to fetch datasheet fields schema"); } const fieldsSchema: FieldFormatJSONSchema = aitableService.getFieldsJSONSchema(result.data.fields); return formatToolResponse({ success: true, data: fieldsSchema }); } catch (error) { console.error("Error in list_database_fields:", error); return formatToolResponse({ success: false, message: error instanceof Error ? error.message : "Unknown error occurred" }, true); } } );
• src/index.ts:187-212 (handler)

  Core handler logic for executing the tool: validates input, fetches raw fields schema from API via service, formats into LLM-compatible JSON schema, and returns standardized tool response.
  async ({ node_id }) => { try { if (!node_id) { throw new Error("The datasheet ID (node_id) is required."); } const result = await aitableService.getDatasheetFieldsSchema(node_id); if (!result.success) { throw new Error(result.message || "Failed to fetch datasheet fields schema"); } const fieldsSchema: FieldFormatJSONSchema = aitableService.getFieldsJSONSchema(result.data.fields); return formatToolResponse({ success: true, data: fieldsSchema }); } catch (error) { console.error("Error in list_database_fields:", error); return formatToolResponse({ success: false, message: error instanceof Error ? error.message : "Unknown error occurred" }, true); } }
• src/index.ts:184-186 (schema)

  Input validation schema using Zod, requiring a single 'node_id' string parameter.
  { node_id: z.string().describe('The ID of the database to fetch records from.'), },
• src/aitableService.ts:367-379 (helper)

  Helper method in AitableService that performs the API call to retrieve the raw fields schema from the AITable '/v1/datasheets/{node_id}/fields' endpoint.
  public async getDatasheetFieldsSchema( node_id: string ): Promise<ResponseVO<{fields: FieldSchemaVO[]}>> { if (!node_id) { throw new Error("The datasheet ID (node_id) is required."); } const endpoint = `/v1/datasheets/${node_id}/fields`; return this.fetchFromAPI(endpoint, { method: "GET", }); }
• src/aitableService.ts:281-312 (helper)

  Helper method that transforms raw FieldSchemaVO[] into a structured JSON schema (FieldFormatJSONSchema) suitable for LLM structured outputs, mapping field types to appropriate Zod/JSON schema keywords.
  public getFieldsJSONSchema(fields: FieldSchemaVO[]): FieldFormatJSONSchema { const schema: { type: string; properties: Record<string, unknown>; additionalProperties: boolean; required: string[]; } = { type: "object", properties: {}, additionalProperties: false, required: [], }; fields.forEach((field) => { const keywordsForField = this._getKeywordByFieldType(field); // If the field type is not supported, we skip it if (keywordsForField) { schema.properties[field.name] = keywordsForField; schema.required.push(field.name); } }); return { type: "json_schema", json_schema: { name: "fields_in_datasheet", schema, strict: true, }, }; }