validate_plan

A code-review command that checks whether completed work matches an implementation plan and its stated success conditions.

In plain words
What is it for?
Use it to inspect the plan, review recent code changes, run checks and tests, and report deviations or remaining issues.
Why use it?
It helps find missing work, unexpected changes, and unverified requirements before the implementation is considered complete.

Command

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/jeffh/claude-plugins/validate_plan
Clone the repo
git clone --depth 1 https://github.com/jeffh/claude-plugins
Per session 11 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,116 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 94% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00011 $0.01116
Opus 5 $0.00005 $0.00558
Sonnet 5 $0.00002 $0.00223
Haiku 4.5 $0.00001 $0.00112

Measured 2d ago against content hash 5f28ac5c0671, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

validate_plan scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

94% identical to validate_plan — 7 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

humanlayer/commands/validate_plan.md · 167 lines

How it starts

The opening of the file, as written. The whole thing — 167 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Validate Plan

You are tasked with validating that an implementation plan was correctly executed, verifying all success criteria and identifying any deviations or issues.

Initial Setup

When invoked:

  1. Determine context - Are you in an existing conversation or starting fresh?

    • If existing: Review what was implemented in this session
    • If fresh: Need to discover what was done through git and codebase analysis
  2. Locate the plan:

    • If plan path provided, use it
    • Otherwise, search recent commits for plan references or ask user
  3. Gather implementation evidence:

    # Check recent commits
    git log --oneline -n 20
    git diff HEAD~N..HEAD  # Where N covers implementation commits
    
    # Run comprehensive checks
    cd $(git rev-parse --show-toplevel) && make check test
    

Validation Process

Step 1: Context Discovery

If starting fresh or need more context:

  1. Read the implementation plan completely

  2. Identify what should have changed:

    • List all files that should be modified
    • Note all success criteria (automated and manual)
    • Identify key functionality to verify
  3. Spawn parallel research tasks to discover implementation:

    Task 1 - Verify database changes:
    Research if migration [N] was added and schema changes match plan.
    Check: migration files, schema version, table structure
    Return: What was implemented vs what plan specified
    
    Task 2 - Verify code changes:
    Find all modified files related to [feature].
    Compare actual changes to plan specifications.
    Return: File-by-file comparison of planned vs actual
    
    Task 3 - Verify test coverage:
    Check if tests were added/modified as specified.
    Run test commands and capture results.
    Return: Test status and any missing coverage
    

Step 2: Systematic Validation

For each phase in the plan:

  1. Check completion status:
    • Look for checkmarks in the plan (- [x])
    • Verify the actual code matches claimed completion

Read the full file on GitHub · 167 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 167 lines · 11 tokens per session scan A 5f28ac5c0671

Subscribe to this mod's changes

validate_plan is a command published in the GitHub repository jeffh/claude-plugins (12 stars, last pushed 18d ago), licensed Apache-2.0. It adds 11 tokens to every session and 1,116 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 94% identical to validate_plan, differing in 7 lines, and is treated as a copy.