MCP
Model Context Protocol. A convention for exposing tools and data to assistants.
What MCP does not show
Publishing an MCP endpoint is a capability, not a visibility measure.
Where MCP comes up on this site
- How to check an MCP server is safe before an agent connectsConflicting instructions to machines are not limited to MCP servers: across every full scan CrawlCheck has run, of sites publish an instruction aimed at agents or AI crawlers that contradicts their own robots.txt, such as a content-use signal under the *…
- MCP Registry census: what 25,983 endpoints answeredThe official MCP Registry is where agents and their builders go to find servers.
- MCP reliability, October 2026: 39,484 handshakes measuredAn agent that connects to a remote MCP server is trusting that the server answers, and that its tools are the ones the agent saw last time.
- MCP servers that ask for a login: what 1,366 request firstAn agent that connects to an MCP server on someone’s behalf usually has to log in, and the login decides what the agent can do afterwards.
- Screaming Frog vs Sitebulb vs CrawlCheck: AI crawler auditsIn Semrush, Ahrefs, Screaming Frog and Sitebulb, the AI sits inside the audit: Semrush’s AI Search Site Audit view flags issues it associates with visibility in LLMs, Screaming Frog runs custom prompts through OpenAI, Gemini, Ollama or Anthropic as it…
Definitions that name MCP
MCP server · MCP client · MCP host · MCP tool · MCP transport · JSON-RPC · tool poisoning · tool lockfile · tool shadowing · MCP preflight · high-risk field · protected-resource metadata · PKCE
Related terms in Machine files
The files addressed to machines rather than readers, and what publishing one does and does not buy.
llms.txt · llms-full.txt · agents.md · entity map · entity map parity · machine layer · well-known URI · agent card · sitemap index · OpenAPI specification · ai.txt · Tool definition · SKILL.md · sitemap origin error · soft 404 on a machine file · tdmrep.json · TDM exception · security.txt · Content Signals · HTTP Message Signatures · changefreq and priority · staging leak · host duplicate
Questions about MCP
What is MCP?
Model Context Protocol. A convention for exposing tools and data to assistants.
What does MCP not show or guarantee?
Publishing an MCP endpoint is a capability, not a visibility measure.
Which area of the glossary does MCP belong to?
Machine files: The files addressed to machines rather than readers, and what publishing one does and does not buy.
← well-known URI · agent card →
See it in the full glossary · 772 terms across 19 areas.
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