"A server for building out n8n from scratch" matching MCP connectors:

The OpenRouter MCP server plugs OpenRouter into the AI tools you already use. Once connected, your assistant can pull live OpenRouter data (models, prices, your credits, rankings, and docs) and send quick test messages, all without leaving your editor.

Federated search of books and papers, BibTeX/RIS citations, open-access retrieval and reading.

Validate startup ideas with real people asking for them, each quote linked to its source.

MCP server for generating rough-draft project plans from natural-language prompts.

IBGE: geography, census, economy and health from the official APIs, with provenance. 21 tools.

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

Reference data for prediction markets: graded resolution clarity, cross-venue links, provenance.

Analytical memory for AI agents: a real Postgres queried in plain English over MCP. One command.

290+ quality-scored API capabilities for AI agents across 27 countries via MCP.

Deterministic calendars, seasons, moon phases, retrogrades, and symbolic systems as stable JSON for AI agents via MCP. Gregorian dates 1900–2100; same date → same bytes.

Read-only MCP server for the OrchestKit docs: full-text search + Markdown fetch. No auth.

Validated SaaS opportunities mined from real user complaints across 8 sources.

Agentic Finance: 500+ tools for AI agents over x402 or MPP, free via PoW, or prepaid card credits

Agent intake desk for property renovation. Read only, CORS open, fail closed, receipts recompute.

Twenty-two paid x402 and MPP tools for agent discovery, payment safety, data, and DeFi.

The Brain Layer for AI Trading Agents — quant calls + cross-venue arb across perp venues via MCP.

Check internet providers, plans, speeds, and known pricing at a specific U.S. street address.

MCP server for Brazilian Federal Senate open data (legislative, administrative, e-Cidadania).

Independent pre-transaction audit for construction estimates. Free, and every verdict recomputes.

Website QA for your coding agent: audit SEO, performance, security, accessibility over MCP.