"How to create draft emails using Gmail's support agent class" matching MCP connectors:

Free platform to test MCP clients without installing anything. Create mock tools with dynamic templates, configurable delays, conditions (if/then), and response sequences. Supports JSON-RPC 2.0 over Streamable HTTP. Built-in text_echo and json_echo tools. Rate-limited tiers: anonymous (5 calls/min, 1 mock tool), registered (10 calls/min, 4 mock tools), premium (60 calls/min, unlimited). Zero setup — no install, no registration required. More info: https://www.testmcp.dev

Point Gecko at an OpenAPI spec; get first-call-correct, auth-hidden agent tools.

Point Claude Code, Qwen Code, Cursor, or any MCP client at https://docs.jmeter.ai/api/mcp and your agent answers JMeter questions grounded in this documentation, with a source link for every answer. Free, no API key, no signup.

Deterministic JSON checks with signed evidence and x402-paid execution

Create hosted mock REST APIs as tools: seed fake data, import specs, query, write, snapshot. Free.

Instant no-signup webhook & HTTP-request inspector for testing webhooks and agent tool-callbacks.

Verify x402 endpoints before payment or publish service profiles for agent discovery.

Debug webhooks from your AI agent: inspect and replay captured webhooks on localhost.

End-to-end API testing — generate and run tests from OpenAPI, curl, Postman, or real user traffic.

MCP server that delivers up-to-date Bitrix24 REST API documentation.

An MCP server that provides tools to validate an email address using Dilli Email Validation API.

MCP server for AI access to SmartBear tools, including BugSnag, Reflect, Swagger, PactFlow, QTM4J.

MCP server for AI access to Swagger by SmartBear.

A basic MCP server to operate on the Postman API.

API and website monitoring that validates the JSON a response returns, not just its status code. Create endpoint checks, pull incident reports carrying the actual failed payload, and read health scores from your editor.

Receive, inspect, replay and deliver webhooks — with signature verification and agent triggers.

Simceptor is an AI-native Mock API simulation platform with a built-in MCP server. It enables AI agents to create, inspect, update, and test dynamic mock APIs, conditional response rules, stateful session simulations, and network latency directly from context.

AI-native mock API server with MCP. Create REST/SOAP mocks from Claude, Cursor, or Windsurf.

MCP server (stdio): validate JSON against JSON Schema (draft-07 / 2020-12) via the AgentForge API

A paid remote MCP for developer endpoint scanner MCP, built to return verdicts, receipts, usage logs