Pieces

1. Terminal. TUI that asks the brain which leg should answer. Bare prompts included.
2. Brain. Go service on loopback (127.0.0.1:14097). Director plan, value ranking, dispatch, assess, record.
3. Runtimes. opencode serve for remote models, or vendor CLIs (claude -p, codex exec, cursor-agent -p) as subprocesses.
4. Files. ~/.captaincode/ holds the ledger, run logs, registry overlay, priors, and per-folder state.

One task, end to end

1. Triage. Deterministic class and domain heuristics, with a lightweight model check when confidence is low.
2. Route. Routine tasks use value ranking; high-complexity tasks and explicit team requests can use a director plan.
3. Fit the prompt. Prune deterministically, summarise only if still over budget, re-attach the first instruction.
4. Dispatch. An opencode session pinned to the project directory, or a vendor CLI subprocess.
5. Watch. First-event, idle, and stall timers plus a hard cap.
6. Handle failure. Eligible provider failures can reroute; useful partial output is preserved and labeled instead of blindly rerunning. Rate limits, outages and harness faults are recorded separately.
7. Record. One ledger line and one scorecard update.

Value ranking

value(leg, class) = w_q·quality/10 − w_c·cost/cost_ref − w_l·latency/lat_ref

Candidates must clear a quality bar τ for the class. Cost and latency are normalised against absolute references. Subscription legs carry pressure inferred from observed rate limits instead of price. This is not an exact remaining-quota meter. If no candidate clears the bar, the implementation can fall back to a configured ladder.

Workspaces

One brain serves every terminal on the machine. Each terminal is open in one folder (workspace). Workers run there; that folder's activity feed and loops are the ones its sidebar shows. Leg cooldowns and the scorecard are shared: a rate limit is per account, not per folder.

OpenAI-compatible surface

captain brain exposes /v1/chat/completions where the model id is a leg name. Anything that can talk to an OpenAI endpoint can drive it. Control surfaces (/team, /parallel, /repeat, /context, /oss, /deterministic, /btw, /interrupt, /captain) are intercepted before dispatch. /btw <note> posts out-of-band to /v1/btw and steers a running turn via the Steer handle for claude (stdin stream-json) and opencode legs (session merge); unsupported legs receive it as the next turn. /interrupt stops the in-flight worker and keeps a handoff or marked partial. /oss and /deterministic narrow the worker pool (open weights, or ADI-green serving tuples with OpenRouter pin); see ADI. Bare user prompts use Captain’s routing path; routine turns can skip the director model.