# Decisions log

## 2026-09-18 Project plan and working agreements
- Goal: agent-first toolkit; the player asks, the agent answers by running tools against live data. Not an end-user app.
- PRUNplanner source (`ref/`) is the source of truth for mechanics; conflicts with the old handoff resolved in its favour (`docs/mechanics.md`).
- Scope: whole universe, default region Antares (CX AI1). Python in `.venv`, secrets in `.env`, git branch `master`. No commits unless the player asks.
- Every reported opportunity must include market saturation (buildings the market can absorb, fill-price ROI, absorbable profit/day). Reason: PRUNplanner's ROI Overview ranks recipes with no depth awareness (e.g. 0.25 day ROI on recipes 2 buildings saturate).
- PRUNplanner integration: API key auth (`Authorization: Api-Key <key>`); plans can be created/updated via `/planning/plan/`. Writes only create/update/delete plans prefixed `[PuGa]` (enforced in `tools/plan_push.py`); never touch the player's other plans. Deleting is allowed only on request (or for throwaway test plans the tool itself made). When the player explicitly asks for a plan, creating it directly is fine; show the dry run in the reply.

## Model and review policy
- Default: Sonnet 5 does the building (API plumbing, CLIs, ports, tests).
- Bigger model (Agent tool `model: opus` or `fable`, fresh context, brief with files and question) is allowed and expected at these points:
  1. Saturation model design, before building it, and again on real output.
  2. Econ formula port (efficiency stack, workforce, hab LP, extraction) checked against PRUNplanner numbers.
  3. `plan_push` payload handling and the own-plans-only guard.
  4. Big-money recommendations (e.g. BHP go/no-go, roughly 100k AIC): independent second opinion on the numbers.
- If a bigger-model spawn is refused, tell the player and ask them to run the review.
- Routine tool building is not reviewed by a bigger model.