mock_api_response

Generate realistic mock API responses from JSON Schema specifications for testing and development purposes.

Instructions

Generate realistic mock API responses from a JSON Schema. Supports nested objects, arrays, string formats (email, uuid, date-time, url), field-name heuristics, enums, and min/max constraints. Set seed for reproducible output. Returns 1–100 records.

Input Schema

TableJSON Schema

Name	Required	Description
`schema`	Yes	JSON Schema object describing the shape of the mock data
`count`	No	Number of mock records to generate (1–100)
`seed`	No	Optional seed for reproducible output

Implementation Reference

mcp-server/src/index.ts:825-840 (handler)

Handler function for mock_api_response, which delegates the request to the Agent Toolbelt API via callToolApi.

  async ({ schema, count, seed }) => {
    const result = await callToolApi("api-response-mocker", { schema, count, seed });
    const data = result as any;
    const r = data.result;

    const lines = [
      `**Generated ${r.count} mock record${r.count !== 1 ? "s" : ""}** (schema type: ${r.schema.type})`,
      "",
      "```json",
      JSON.stringify(r.data, null, 2),
      "```",
    ];

    return { content: [{ type: "text" as const, text: lines.join("\n") }] };
  }
);

mcp-server/src/index.ts:810-840 (registration)

Registration of the mock_api_response tool.

server.registerTool(
  "mock_api_response",
  {
    title: "API Response Mocker",
    description:
      "Generate realistic mock API responses from a JSON Schema. " +
      "Supports nested objects, arrays, string formats (email, uuid, date-time, url), " +
      "field-name heuristics, enums, and min/max constraints. " +
      "Set seed for reproducible output. Returns 1–100 records.",
    inputSchema: {
      schema: z.record(z.unknown()).describe("JSON Schema object describing the shape of the mock data"),
      count: z.number().int().min(1).max(100).default(1).describe("Number of mock records to generate (1–100)"),
      seed: z.number().int().optional().describe("Optional seed for reproducible output"),
    },
  },
  async ({ schema, count, seed }) => {
    const result = await callToolApi("api-response-mocker", { schema, count, seed });
    const data = result as any;
    const r = data.result;

    const lines = [
      `**Generated ${r.count} mock record${r.count !== 1 ? "s" : ""}** (schema type: ${r.schema.type})`,
      "",
      "```json",
      JSON.stringify(r.data, null, 2),
      "```",
    ];

    return { content: [{ type: "text" as const, text: lines.join("\n") }] };
  }
);

mcp-server/src/index.ts:819-823 (schema)

Input schema definition for mock_api_response.

inputSchema: {
  schema: z.record(z.unknown()).describe("JSON Schema object describing the shape of the mock data"),
  count: z.number().int().min(1).max(100).default(1).describe("Number of mock records to generate (1–100)"),
  seed: z.number().int().optional().describe("Optional seed for reproducible output"),
},

agent-toolbelt