Ansvar docs
ansvar.eu →

MCP basics

Model Context Protocol (MCP) is an open standard from Anthropic that defines how an AI client talks to an external tool server. The Ansvar gateway is an MCP server; Claude, Cursor, VS Code Copilot, ChatGPT and Continue are MCP clients. Once a client adds the gateway, the agent can discover and call its tools the same way it would call any other tool.

What MCP defines

  • Tool discovery — a client lists the server's tools, their JSON schemas, and the scopes they require. The gateway filters that list by tier, so a free-tier client never sees a Company-tier tool.
  • Tool invocation — typed parameters in, typed result out, errors carried in a standard envelope. The agent composes a tool call; the server returns the answer.
  • Prompts — server-defined templates the agent surfaces as slash-commands. Ansvar's tender-review workflow ships three (tender-review-decompose, tender-review-regulatory-map, tender-review-red-team); other workflows are reached directly through tool calls.
  • Transport — the gateway uses streamable HTTP at https://gateway.ansvar.eu/mcp. OAuth 2.1 with Dynamic Client Registration secures the channel.

Why MCP, not REST

MCP is built around an agent loop: the agent discovers tools at runtime, picks one, calls it, reads the result, and decides what to do next. REST endpoints assume the caller already knows which endpoint to hit. For a fleet of ~370 specialist data sources sitting behind a routing layer, MCP's discoverability is the difference between "the agent figures out which jurisdiction to query" and "the developer wires up 370 SDKs by hand."

Why MCP, not RAG

RAG retrieves chunks of embedded text from a vector store and hopes the model synthesises them faithfully. The gateway does the opposite: each MCP behind it owns its corpus natively (regulator databases, FTS indexes, structured schemas) and returns the precise article the agent asked for, with the source URL and publisher attached. Hallucination at the retrieval step is the single biggest failure mode in compliance LLM work; MCP cuts it out by replacing the embedding round-trip with a tool call to the regulator's own data.