preflight-checkslisted

# Pre-flight Checks Reference document for the pre-flight policy. The executable bash lives in `plugins/flow/commands/start.md` (Phase 0) — that is the single source of truth that runs at workflow start. This skill describes **what each check enforces and why**, so the policy can be reviewed, audited, and extended without untangling shell logic. ## Iron Law **NO LLM CALLS IN PRE-FLIGHT.** Every check is a bash command with a pass/fail exit code. If pre-flight fails, the workflow stops before spending any tokens on planning. ## What Pre-flight Protects Pre-flight is the cheapest possible filter. It runs before EXPLORE, before any agent dispatch, and before any token-spending reasoning. The goal is to fail fast on conditions that would invalidate everything downstream — saving both wall-clock time and LLM cost. If pre-flight is honest about what it can and cannot prove, downstream phases can trust their preconditions and stop re-checking them. ## The Six Checks (and why each exists) | # | Check | Failure mode it prevents | |---|-------|--------------------------| | 1 | Clean git state (no uncommitted changes) | Starting a feature branch on top of unrelated dirty state, then accidentally including those changes in the PR. | | 2 | Not on detached HEAD | Creating commits that have no branch reference and silently disappear when the workflow checks out something else. | | 3 | `gh` CLI authenticated | Spending tokens on planning, then failing at the first `gh issue view` cal