plan-critic

plan-critic is a skill for Claude Code from cunhaax/ai-workflow. It costs 55 tokens per session (1,184 once invoked), scanned A, original, MIT.

A plan-review skill that tests an implementation plan for risks before coding begins. A pre-mortem imagines failure in the future, while inversion asks what would make the plan fail.

In plain words
What is it for?
It reviews a draft plan using pre-mortem, inversion, analysis of assumptions that carry the plan, and consistency checks, with repository documentation available as context.
Why use it?
It can expose flawed assumptions and contradictions before they become code, when changing the plan is cheaper than fixing the implementation.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions subagents; mentions AGENTS.md.

Part of the ai-workflow plugin — 8 skills, 4 agents, 2 MCP servers shipped together

Good fit It reviews a draft plan using pre-mortem, inversion, analysis of assumptions that carry the plan, and consistency checks, with repository documentation available as context.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/cunhaax/ai-workflow/plan-critic
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.

Any agent
npx skills add cunhaax/ai-workflow --skill plan-critic
Clone the repo
git clone --depth 1 https://github.com/cunhaax/ai-workflow

Made for: Claude Code.

Or install ai-workflow, the plugin that ships this one along with the rest of its 8 skills, 4 agents, 2 MCP servers.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for plan-critic

README.md
[![agentmods](https://agentmods.dev/badge/skills/cunhaax/ai-workflow/plan-critic.svg)](https://agentmods.dev/skills/cunhaax/ai-workflow/plan-critic)
Your own site
<a href="https://agentmods.dev/skills/cunhaax/ai-workflow/plan-critic"><img src="https://agentmods.dev/badge/skills/cunhaax/ai-workflow/plan-critic.svg" alt="Measured on agentmods" height="20"></a>
Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,184 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found 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 5.1 $0.00055 $0.01184
Opus 5 $0.00028 $0.00592
Sonnet 5 $0.00011 $0.00237
Haiku 4.5 $0.00006 $0.00118

Measured 7d ago against content hash 8ea78b83281b, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

plan-critic 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 7d 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.

plugins/ai-workflow/skills/plan-critic/SKILL.md · 144 lines

How it starts

The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/plan-critic — Plan Critique

Apply this skill to critique a draft implementation plan before any code is written. The goal is to find weaknesses in the plan itself, not to rewrite it. The developer reads the critique alongside the plan and decides what to amend.


Stance

Plans are load-bearing. If the plan is wrong, downstream review and QA mostly verify that the wrong thing was built correctly. Your job is to attack the plan before it becomes commitment.

You do NOT critique writing quality, formatting, or template completeness. You critique whether the plan, as written, will produce a good outcome.


Inputs

You receive:

  • A draft implementation plan as markdown text.
  • Read-only access to the repository: ADRs in docs/adr/, product docs in docs/product-context/, existing source code, module-level AGENTS.md files.

Methods

Apply EACH of the four methods below. Each must produce findings or an explicit "no concerns surfaced by this method, because [reason]" statement. Skipping a method silently is not acceptable.

1. Pre-mortem

Assume this feature shipped 30 days ago and caused a production incident, support escalation, or regulatory complaint. Write 2–3 plausible failure scenarios in 1–2 sentences each. For each, identify whether the plan addresses it and how. Unaddressed scenarios become findings.

2. Inversion

Read the plan as a recipe for guaranteeing failure. What could an adversarial implementer do, while technically following the plan as written, that would produce a broken or unsafe feature? List 2–3 such gaps.

3. Load-bearing assumptions

List the 3 most load-bearing assumptions in the plan — assumptions about user behaviour, data shape, system state, regulation, third-party behaviour, or scale. For each, ask: what if it's wrong? Is the plan robust to that? If not, flag it.

4. Consistency with prior decisions and product intent

Read relevant ADRs and product docs in docs/product-context/. Flag any contradictions with past architectural decisions or the documented product vision/strategy that the plan does not acknowledge.

Read the full file on GitHub · 144 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. 7d ago First seen · 144 lines · 55 tokens per session scan A 8ea78b83281b

Subscribe to this mod's changes

plan-critic is a skill published in the GitHub repository cunhaax/ai-workflow (5 stars, last pushed 11d ago), licensed MIT. It adds 55 tokens to every session and 1,184 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.