Hermes MCP Bridge

What it is

The coordinator bridge is a core GJC contract with multiple adapters, not an MCP-only product direction. Hermes is one coordinator preset. The bridge lets external coordinators register visible sessions, read polling status, send bounded turns, answer questions, and write reports while keeping mutation classes fail-closed until configured.

Standard setup

The default mode is render-only. Install mode writes a portable Hermes MCP setup package with explicit roots, repo identity, and session command configuration.

Coordinator turn model

Hermes coordinators should treat turns, not terminal scrollback, as the unit of work. The bridge stores durable turn/question/report state and exposes bounded polling snapshots. Use gjc_coordinator_register_session to attach an already-visible tmux-backed GJC pane instead of creating a hidden session.

Event watch surface

gjc_coordinator_watch_events is the long-poll event journal surface for Hermes-style agents. It returns bounded event records, latest_seq, timeout status, and explicit transport metadata (mcp: long_poll, no push subscriptions). Consumers should poll by sequence number and avoid treating terminal scrollback as authoritative state.

Safety posture

• Read-only by default.
• Mutation classes require explicit startup and per-call authorization.
• Workdir roots, repo identity, safe session tokens, and tmux target liveness are validated before state writes.
• Generated GJC-native worktree commands preserve project/session identity better than unmanaged external worktrees.