behalf-proxy

Overview ¶

Command behalf-proxy is the behalf MCP stdio interposer — the canonical v1 capture surface (D4, Q44). It wraps a real MCP server:

behalf-proxy --state DIR [--policy FILE] [--chain FILE] [--spool DIR] -- SERVER [ARGS...]

Newline-delimited JSON-RPC crosses in both directions verbatim, except that client->server `tools/call` requests gain the two legal `params._meta` keys (`sh.behalf/chain`, `baggage`). Every tools/call is spooled as an intent before it is forwarded and closed as a signed receipt when the response arrives (Q4, Q48).

The proxy does not touch the log: `behalf-log drain --spool DIR --dir LOGDIR` moves the spool into it (Q57, Q46).

In an MCP client config, replace the server command with this one:

{"command": "behalf-proxy",
 "args": ["--state", "~/.behalf", "--", "my-mcp-server", "--flag"]}