json_query_jsonpath
Extract specific data from large JSON files by evaluating JSONPath expressions. Ideal for precise querying and retrieving values within complex JSON structures.
Instructions
Query a JSON file using JSONPath. Use to get values precisely from large JSON files.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| file_path | Yes | Absolute path to the JSON file. | |
| jsonpath | Yes | JSONPath expression to evaluate |
Implementation Reference
- src/server.ts:35-60 (registration)Registers the 'json_query_jsonpath' tool using McpServer.tool, including description, input schema with Zod, and inline async handler.
server.tool( 'json_query_jsonpath', 'Query a JSON file using JSONPath. Use to get values precisely from large JSON files.', { file_path: z.string().describe(PATH_ARG_DESCRIPTION), jsonpath: z.string().min(1).describe('JSONPath expression to evaluate'), }, async ({ file_path, jsonpath }) => { try { const resolvedPath = path.resolve(file_path); const results = await JsonUtils.queryByJsonPath(jsonpath, resolvedPath); return { content: [ { type: 'text', text: JSON.stringify(results, null, 2), }, ], }; } catch (error) { return getErrorResponse(error); } }, ); - src/server.ts:42-59 (handler)The tool handler function that resolves the file path, delegates to JsonUtils.queryByJsonPath, formats the result as MCP content, and handles errors.
async ({ file_path, jsonpath }) => { try { const resolvedPath = path.resolve(file_path); const results = await JsonUtils.queryByJsonPath(jsonpath, resolvedPath); return { content: [ { type: 'text', text: JSON.stringify(results, null, 2), }, ], }; } catch (error) { return getErrorResponse(error); } }, - src/jsonUtils.ts:21-35 (helper)Core helper method that reads the JSON file, applies JSONPath query using jsonpath-plus library, and returns array of path-value results.
static async queryByJsonPath(path: string, jsonFile: string): Promise<JsonPathResult[]> { const data = await this.readJsonFile(jsonFile); // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion const results = JSONPath({ path, json: data as object, resultType: 'all', }) as { path: string; value: unknown }[]; return results.map((result) => ({ path: result.path, value: result.value, })); } - src/server.ts:39-41 (schema)Zod schema defining input parameters: file_path (string) and jsonpath (non-empty string).
file_path: z.string().describe(PATH_ARG_DESCRIPTION), jsonpath: z.string().min(1).describe('JSONPath expression to evaluate'), }, - src/types.ts:1-4 (schema)TypeScript interface defining the output structure for JSONPath query results.
export interface JsonPathResult { path: string; value: unknown; }