"Capture The Flag (CTF) cybersecurity competitions and challenges" matching MCP connectors:
GET /v1/connectors — MCP directory API referenceMatching Connector Tools:
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.
Bounded KVP, RAG search, and wipe receipts for agent jobs over remote MCP
The first low-latency wire service purpose-built for AI agents. Ingests 54+ public APIs and 71k RSS feeds across 232 countries, outputs CWF (Cognitive Wire Format) – 80% shorter than JSON, sub-second WebSocket delivery. 9 MCP tools: get_latest_signals, search_signals, get_fused_signal, scope_signals, get_facet_manifest, list_facets, get_related_signals, list_data_sources, get_billing_profile. 26 citable fusion products with verifiable formulas – no black-box scores.
A semantic search server that gives AI assistants instant access to Dodo Payments documentation and knowledge base.
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.
Shared error→fix knowledge base for AI coding agents. Search is open with no key; agents query mid-task via REST or MCP and contribute back what they verified worked. New submissions are held from public results until community-upvoted or moderator-approved; disputes stay attached to a fix rather than just lowering its score.
**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
Cross-vendor AI memory over MCP. One semantic store, readable and writeable from every MCP client.
Read-only answers and semantic search for wiki.private.law, served by the Mothership runtime.
Free OpenAI-compatible inference with signed provenance receipts and 3 focused MCP tools.
Shared semantic graph for AI reviews, classification and structured memory across AI assistants.
Serper MCP — wraps the Serper Google Search API (serper.dev)
Free MCP API to create AI chat personas for websites — upload knowledge, search, and chat
TestGraph is a shared structured knowledge and review graph for AI agents. Its MCP server lets ChatGPT, Claude and other AI clients store, retrieve and collaboratively refine reviews, entities, relationships and semantic classifications, providing persistent knowledge that can be reused across models and conversations.
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.
Source-traced evidence research for AI agents. We organise the evidence; you decide.
Recall (recall.it) — your AI knowledge base / 'second brain'. Via the official API: semantic search
Serve a folder of Markdown notes as an MCP server: hybrid search, reading, and sourced answers.
Independent fact-checking for AI answers: a verdict and sources for every claim.
Your private knowledge base: upload documents (.md, .txt, .docx, PDF, images), the platform indexes
