"Free PostgreSQL Database Solutions" matching MCP connectors:

Scan/purge hidden text & score web domains: TLS, DNS, headers, speed. Free scans, $0.01 actions.

Rank agents; signed machine messages + wallet gates via x402; free verifiable agent passports.

Structured aquarium, marine, terrarium and paludarium data for AI agents.

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

Eligibility-first UK & EU grant discovery, inside ChatGPT and Claude. Checks eligibility before recommending, explains why each grant fits, and cites the funder's own page on every answer — with an honest "competition_risk: unknown" when the data isn't there. 6 tools: search, fetch, find_opportunities, should_apply, explain_opportunity, complete_profile. Transport: Streamable HTTP. Auth: OAuth 2.1 + PKCE. Free to install, no card required.

Universal pay-per-call tool API for AI agents. Web search, price feeds, hive memory, LLM routing, code sandbox. Free tier (10 calls/day, no signup). x402 payments on Base + Solana.

Search foods, compare nutrients, and look up the full USDA FoodData Central database.

Pay-per-use tool API for AI agents. Free tier, x402 USDC micropayments, or API key.

Point-in-time, survivorship-free SEC EDGAR fundamentals + smart-money signals for AI agents.

Free, keyless real-time currency conversion and exchange rates for any currency pair.

Free, keyless real-time weather and 7-day forecasts for any city worldwide.

Search French mountain holiday rentals and contact owners directly — commission-free.

Verify PyPI and npm packages, symbols, and version diffs against real artifacts. Free, no account.

Free AI-powered DXP tools by Oshyn: GEO & Reliability scan, Choose New DXP and Estimate DXP Budget.

Search live startup jobs from Claude, Cursor, or ChatGPT via MCP. Free, no account needed.

90+ free tools, Claude & ChatGPT: prices, options, SEC filings, 13F, insider, congress, transcripts.

B2B people and company data for AI agents. Search 700M+ professionals by role, company, and industry. Reveal verified work emails and direct phone numbers inline. Free to search, 1 credit per verified reveal. Supports Claude Desktop, Claude Code, Cursor, and any MCP client.

Free text/image → 3D: generate, rig, avatar-ify, and refine GLB models. No auth, no payment.

Hireable AI-visibility service: get a business named in AI answers. Free audit + x402 hire.

check-package: block malicious npm/PyPI deps before your AI agent installs them. Free, no key.