spec-critic

spec-critic is an agent for Claude Code from masanami/claude-harness. It costs 53 tokens per session (2,851 once invoked), scanned A, original, no licence file.

An agent that critiques feature specification documents for testable acceptance criteria, internal consistency, and usefulness for later implementation.

In plain words
What is it for?
It is for reviewing specifications before development and checking whether their requirements can be verified.
Why use it?
It can expose unclear requirements or contradictions before they cause implementation problems.

Agent for Claude Code

Written for Claude Code: effort in frontmatter. Also seen: model in frontmatter.

Part of the claude-harness plugin — 23 skills, 22 agents, 1 hook shipped together

Good fit It is for reviewing specifications before development and checking whether their requirements can be verified.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/masanami/claude-harness/spec-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.

Clone the repo
git clone --depth 1 https://github.com/masanami/claude-harness

Made for: Claude Code.

Or install claude-harness, the plugin that ships this one along with the rest of its 23 skills, 22 agents, 1 hook.

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 spec-critic

README.md
[![agentmods](https://agentmods.dev/badge/agents/masanami/claude-harness/spec-critic.svg)](https://agentmods.dev/agents/masanami/claude-harness/spec-critic)
Your own site
<a href="https://agentmods.dev/agents/masanami/claude-harness/spec-critic"><img src="https://agentmods.dev/badge/agents/masanami/claude-harness/spec-critic.svg" alt="Measured on agentmods" height="20"></a>
Per session 53 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,851 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 unknown 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 $0.00053 $0.02851
Opus 5 $0.00026 $0.01425
Sonnet 5 $0.00011 $0.00570
Haiku 4.5 $0.00005 $0.00285

Measured yesterday against content hash f39243009672, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

spec-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 yesterday.

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.

agents/spec-critic.md · 79 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. yesterday Changed · +1 lines f39243009672
  2. 7d ago First seen · 78 lines · 53 tokens per session scan A 80ff831b18fe

Subscribe to this mod's changes

spec-critic is an agent published in the GitHub repository masanami/claude-harness (5 stars, last pushed yesterday), with no licence file. It adds 53 tokens to every session and 2,851 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.

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