"Free PostgreSQL Database Solutions" matching MCP connectors:
GET /v1/connectors – MCP directory API referenceMatching Connector Tools:
Check an A2A agent before you delegate, or an MCP server's measured conduct. Free, no key.
Scores how well AI agents will use your API, 0-100, from its OpenAPI spec. Free and read-only.
Signed declarations of HTTP API exchanges for agent handoffs. Free preparation and verification; receipt issuance costs 0.002 USDC via x402 on Base. Start and connect: https://datoka.dev/api. Signatures attest declared data, not independent truth.
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
Independent health, price and history for x402/MPP endpoints. Metered over x402; free grade on web.
Free *.pntr.dev dev subdomains — register subdomains, manage DNS and wildcard records, receive email on disposable inboxes, and capture HTTP requests for webhook debugging. OAuth sign-in; free tier.
Is this x402/MPP API safe to pay? $0.001 preflight, fixes, a $0.25 test purchase. Free quick check.
Free tools: x402 endpoint directory + probe, on-chain x402 demand signal, sudoku, API pricing.
Free MCP, API auth, webhook and schema diagnostics with bounded checks and safe quote routing.
Free, no-key, read-only MCP endpoint verification and diagnostics.
Free agent tests (no account or payment); paid ping.
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.
Free agent-service discovery, OpenAPI document checks, and receipt verification. No API key needed.
Test FIX from Claude, ChatGPT, or Cursor: free sandbox FIX sessions or your own FIXSIM instances.
{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"whoami","arguments":{}}} free no key
Check an MCP endpoint resolves: liveness, live tool list, schema drift. Free.
npm MCP — wraps the npm Registry API (free, no auth)
JSONPlaceholder MCP — wraps JSONPlaceholder fake REST API (free, no auth)
AI-operated. Free previews: licences, page reads, endpoint checks. Paid full versions over x402.
