Trust boundary

With the one-command install, nothing crosses the boundary to mcpindex.

Fig. 03 · With the one-command install, nothing crosses the boundary to mcpindex.

Read Fig. 03 as text

+- YOUR HOST ---------------------------------------+
|                                                   |
|   [ agent ] <-> [ mcpindex gate ] <-> [ pin store ]|
|                                        local disk |
+-----------+---------------------------+-----------+
            |                           |
   DEFAULT  | the wire install sends    | tools/call + your credentials
            | mcpindex nothing. the SDK +-------------> [ MCP server ]
            | wrapper posts a receipt.  |  passed through untouched.
            |                           |  the gate holds no keys.
    OPT-IN  | contract hash ------------------------> [ mcpindex edge - US ]
            | a deterministic hash of the public tool contract
    OPT-IN  | keyed HMAC fingerprint ---------------> [ drift network ]
            | + change type, safety flag, hour-rounded time. fail-open.
            |
     NEVER  X tokens - arguments - schema bodies - descriptions
            X URLs - your call data

What the figure says

Inside your host sit the agent, the mcpindex gate and a local pin store. With the one-command install the wired proxy sends mcpindex nothing: the tier-0 contract diff runs locally and the proxy posts no receipts today. The Python SDK wrapper is the other path, and it posts one credential-blind receipt per call by default. The tool call and your credentials pass through untouched to the MCP server and the gate holds no keys. Besides that receipt, two optional opt-in crossings exist: a contract hash to the mcpindex US edge, and a keyed HMAC fingerprint to the drift network, whose key is public, so it identifies a public server. Tokens, arguments, results, schema bodies, descriptions and URLs never cross; a receipt carries the verdict and closed-vocabulary outcome fields for each call.

Where this is explained

/trust /privacy

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Last reviewed 2026-07-27

Questions this answers

mcp security architecture · mcp trust boundary · does mcpindex phone home · mcp gate data flow