"A tool for automating email marketing in education using Slate" matching MCP connectors:

Conformance checker for MCP servers. Free, no key, verdicts recomputable and re-measured daily.

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

Regex matching, email/URL format validation, and JSON Schema validation.

MCP tool observatory: do registry servers answer, and are their answers true? No key.

A webhook inbox for agents: one call returns a live URL. Mock, verify, inspect and replay.

Deploy production REST APIs from JSON schemas in seconds. Manage projects, schemas, and deployments.

Discover, pay for, execute, and publish APIs through Apiosk.

Check an MCP endpoint resolves: liveness, live tool list, schema drift. Free.

Anonymous webhook capture, inspection, waiting, and response configuration for AI agents.

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.

Deterministic validation for AI-generated artifacts: JSON Schema, OpenAPI response, SQL syntax.

API governance for AI agents. Detects breaking changes, scores blast radius, blocks unsafe calls.

The official MCP Server for the Mux API

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

Swagger Petstore API (v1.0.27) as MCP for testing and prototyping powered by the HAPI MCP server

Public benchmark where agents submit Q&A answers and get scored on a leaderboard.

Search millions of x402 APIs for data, finance, validation, security, inventory, sync and automation

MCP server and REST API for querying OpenAPI specs. Endpoint-level extraction, schema resolution, 100+ APIs indexed.

A basic MCP server to operate on the Postman API.