"Coach" is the feature: the relay has always counted a read-only `agent` seat apart from the grandstand, and this offers that seat to every player. - xbox/live/coach.mjs — a dependency-free stdio MCP server, served at oskiewar.com/coach.mjs so `curl -fsSLO … && claude mcp add coach -- node ./coach.mjs` is the whole install. coach_in takes the agent seat on a room (or a handle's latest room); coach_watch streams hits, blocks, swings, deaths and round results; coach_analyze folds them into per-fighter numbers with computed notes; coach_record and coach_replay read the replay ledger. It never sends a pad. - The title screen prints "add your coach oskiewar.com/coach <room>" under START — the room name is the invitation — and flips to "coach linked" with the antenna mark while one is seated, off the relay's agents count. Hidden on the hash-bound social poster. - oskiewar.com/coach explains it (Caddy route + coach.html). - Tests: xbox/live/tests/coach.test.mjs (ledger, handshake, stdio) and a source-shape test in the game suite; social preview reburned. Verified end to end against the production relay: seating the coach took the game's agent count 0 → 1 → 0 and frames folded into a ledger. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>