mcp

Serve a live proxy pool over the Model Context Protocol on stdio, so agent tooling can pull healthy proxies and feed failures back into the same eviction machinery. It is a thin veneer over the same pool used by serve.

mcp is behind the mcp feature, which is off by default. Build with it enabled:

cargo build --features mcp
proxybroker mcp --types HTTP HTTPS

stdout is the MCP JSON-RPC channel; all human-facing logging goes to stderr. The pool fills in the background, so get_proxy may return null until the first proxies land.

Options

Protocol values are exactly as in find. There is deliberately no --max-error-rate / --max-resp-time: those pool thresholds only gate re-admission via the server relay, which the MCP handlers never call.

Exposed tools

The server exposes exactly three tools:

get_proxy

Check out the best healthy proxy for a scheme, optionally filtered to a country. The proxy stays in the pool (it is returned immediately, so it keeps rotating by priority).

Arguments:

Result (or null if none is available):

{
  "proxy": "1.2.3.4:8080",
  "types": ["HTTP", "HTTPS"],
  "avg_resp_time": 0.42,
  "error_rate": 0.0
}

pool_status

A snapshot of the live pool. No arguments. Result:

{
  "total": 100,
  "working": 100,
  "by_protocol": { "HTTP": 80, "HTTPS": 40 },
  "by_country": { "US": 30, "DE": 12 },
  "avg_resp_time": 0.71,
  "errors": {}
}

report_dead

Report a proxy as dead so it is removed from the pool and no longer handed out. The failure happened out-of-process, so the honest action is removal — not synthesizing an error into the histogram.

Arguments:

Result:

{ "removed": true }

See also

• serve — the rotating proxy server over the same pool.
• top — a live TUI dashboard over the same pool.
• feature flags — enabling mcp and store backends.