"Open-Source MCP Server in Python with PostgreSQL and OAuth 2.0" matching MCP connectors:

MarkupBase turns AI-generated Markdown and HTML into durable, versioned artifacts that people can review and discuss. Its MCP server lets agents publish new versions, preserve contextual comments, include hosted images, and respond to feedback through secure account-linked identities, creating a clear human review boundary without requiring real-time editing.

Hosted MCP memory: save sessions/decisions once, search from Claude, Cursor, ChatGPT. EU-hosted FTS.

Deterministic AI agent microtools, no accounts/API keys. fetch_extract: 98% token cut. 38 tools.

For queries a model can't confidently place: resolves or declines. Built to decline, not guess.

A semantic search server that gives AI assistants instant access to Dodo Payments documentation and knowledge base.

MCP server for German & EU law. Verified, citable legal context for any LLM. Daily updates from official sources, hosted in Germany

AI-first file sharing and collaboration. 251 tools give agents a full workspace: file storage, branded shares, comments, workflows, and built-in RAG. 50GB free, no credit card.

**ColdState Knowledge Search MCP Server** https://github.com/daniel-coldstate/coldstate-mcp Semantic search over 64.6M knowledge entries — the structured alternative to web search APIs and web scraping for LLM agents. No crawling, no rate limits, sub-3s responses. Cloud-hosted at services.coldstate.ai

Free mechanical checks for AI text: unnamed counts, dangling references, bad arithmetic, misquotes.

Turn a GitHub repo or docs site into agent-ready context: pack it or search it, over MCP.

Discover, prove, route, and serve small AI specialists with fast RAG and private agent memory.

Semantic search over the Stoic corpus — Marcus Aurelius' Meditations, Seneca's essays, and Epictetus' Discourses, Enchiridion and Fragments. Search by theme or citation, fetch any passage, or get the daily reflection. Public domain translations, no auth.

Know whether an AI agent should REUSE or REFETCH a URL before retrieving it again.

Source-traced evidence research for AI agents. We organise the evidence; you decide.

Independent fact-checking for AI answers: a verdict and sources for every claim.

Collaborative, cache-first web search for agents — cited answers from a shared live-web pool.

Serve a folder of Markdown notes as an MCP server: hybrid search, reading, and sourced answers.

Persistent project context for xAI Grok. IANA-registered .faf format.

Durable, versioned memory for AI assistants. Remote memory needs a Pastepile subscription.

Check claims against a fact-store: consistent, contradicts, or unverifiable — with a receipt.