Where the gate sits

The gate is inside the call path, so a hold actually stops the call.

Fig. 01 · The gate is inside the call path, so a hold actually stops the call.

Read Fig. 01 as text

TODAY          [ your agent ] - - - - - - - - - - - - - -> [ MCP server ]
                                nothing between them

WITH THE GATE  [ your agent ] --> [ mcpindex gate ] --> [ MCP server ]
                                   pin - diff - decide      PROCEED
                                          |                 live contract matches your pin
                                          +--| HELD
                                             the contract changed since you pinned it.
                                             the call never leaves your machine.

               runs on your host - zero credential custody - default build egresses nothing

What the figure says

Without mcpindex an agent calls an MCP server directly with nothing in between. With mcpindex the gate sits in the call path: it pins the contract, diffs it, and either proceeds to the server when the live contract matches the pin, or holds the call and returns it to the agent when the contract has changed. The gate runs on your host, holds no credentials, and the default build egresses nothing.

Where this is explained

//install /docs

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Last reviewed 2026-07-27

Questions this answers

mcp architecture diagram · how does mcp work diagram · mcp interceptor · in-path mcp gate