codex-skills-library: Skill for Codex

Codex Efficiency Benchmark

Goal

Measure whether Codex skills and project process guidance reduce token waste, elapsed time, file scanning, validation churn, and dead ends compared with a minimal baseline.

When to use

Use this skill when you need to compare "with skills" versus "without skills" on a real task, bootstrap, refactor, or recovery workflow.

When not to use

Do not use this skill for unrelated implementation tasks that do not need a control vs treatment comparison.

Inputs

• Project context files such as AGENTS.md, docs/CODEBASE_INDEX.md, and docs/PROJECT_CONTEXT.md.
• A baseline scenario that uses minimal guidance.
• A treatment scenario that uses the relevant skills, docs, and process rules.
• A run log in templates/project/EFFICIENCY_RUN.json format or equivalent project-local JSON.

Workflow

1. Define the scenario, goal, and success criteria.
2. Run or reconstruct the baseline variant with the smallest safe context.
3. Run the treatment variant with the relevant skills and repo rules.
4. Record start and end timestamps, files read, files changed, commands run, validations, rework loops, dead ends, and token usage if available.
5. Compare control and treatment with npm run compare:efficiency or the equivalent script.
6. Explain which metrics improved, which regressed, and why.
7. Capture the decision in docs/CODEX_STATE.md, docs/PLANS.md, or project-local state files.

Quality bar

• The comparison must be the same task, same repo state, and same acceptance criteria.
• Exact token usage is preferred when available from the goal metadata; otherwise record an explicit estimate and source.
• The result must separate real improvements from noise caused by different task scope or validation depth.

Validation

Run the relevant validation for the task plus the benchmark comparison command.

Final response

Report the control/treatment setup, metrics, deltas, confidence limits, and next experiment.