unknowns-first-coding is a Codex skill for risky coding tasks where a wrong assumption would be expensive.
The main idea: before implementing, Codex should separate what is known from what is guessed. It should inspect the repo first, surface important unknowns, ask only questions that materially change the implementation, and proceed on low-risk reversible choices with assumptions clearly logged.
This is not a planning ceremony for every edit. Tiny deterministic changes should stay lightweight: inspect, edit, validate, summarize. The full workflow is for ambiguity with real reversal cost: architecture, public APIs, schemas, migrations, production data, security/privacy/auth/payments/compliance, large refactors, or risky UX semantics.