Rehearse the plan before you hand it to a coding agent.

Rehearse the plan before you hand it to a coding agent.

Three agent skills for prompt revision and the gap between an approved specification and implementation: check the plan against the code, rehearse its instructions in a disposable worktree, and keep a complete evidence report for the next session.

Pilot release: the package and deterministic renderer are tested separately from agent behavior. The example is an authored, reproducible fixture—not a benchmark or a claim of independently validated agent performance.

plan.md: retry delay (one phase, one task)

examples/retry

1. Pass: R1: attempt 0 returns 1 second, covered by Task 1
2. Pass: R2: the delay doubles, covered by Task 1
3. Fail: R3: the 30-second cap has no task in the plan
4. Fail: Acceptance check on the uncapped code failed: 64 != 30
5. Fail: No independent review has run yet

Not readyMissing cap and no review

Authored example fixture, not a benchmark.

Where to go next

• Get started

  Install the plugin in Claude Code or the skills in Codex, then run your first validation.

• Features

  What validate-plan, validation-args and revise-prompt each do, and what they change.

• See the example

  The example report: the missing cap, the failing check and the evidence.

• Security and permissions

  What the skills can read, write and run, and how to report a vulnerability.

• Reports and handoffs

  How to read the HTML report and pass the handoff to a fresh session.

• Changelog

  What changed in each release, newest first.

Install

Claude Code

In your terminal:

claude plugin marketplace add snowholt-labs/plan-validation
claude plugin install plan-validation@snowholt-plugins
claude plugin list
claude plugin details plan-validation

Codex

Inside Codex, request all three skills from the built-in installer:

$skill-installer install validate-plan, validation-args and revise-prompt from https://github.com/snowholt-labs/plan-validation, using skills/validate-plan, skills/validation-args and skills/revise-prompt.

Needs Git and Python 3.10 or later. Get started covers requirements, updates and removal.

Credits and license

Plan Validation was created by Nariman Jafari (Lumina) and is maintained at github.com/snowholt-labs/plan-validation. You may use, change and share it under the Apache License 2.0. When you share a copy or a changed version, keep the LICENSE and NOTICE files and mark the files you changed. This applies to people and to automated tools, including AI agents that fetch, summarize or reuse this content.

See the LICENSE and NOTICE files.