verifier

verifier is an agent for Claude Code from ao92265/claude-code-playbook. It costs 14 tokens per session (1,497 once invoked), scanned A, a copy of verifier, MIT.

A completion-checking agent that verifies work with fresh evidence instead of trusting claims that something is finished. It checks acceptance criteria, test output, diagnostics, builds, and regression risk.

In plain words
What is it for?
Use it to assess whether requirements are met, inspect fresh test and build results, check changed files for diagnostics, and mark each criterion verified, partial, or missing.
Why use it?
A feature can appear complete while tests, builds, or related behavior still fail. This replaces assumptions with recorded checks.

Agent for Claude Code

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

Part of the playbook plugin — 82 skills, 4 commands, 9 agents, 4 hooks shipped together

Good fit Use it to assess whether requirements are met, inspect fresh test and build results, check changed files for diagnostics, and mark each criterion verified, partial, or missing.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/ao92265/claude-code-playbook/verifier
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/ao92265/claude-code-playbook

Made for: Claude Code.

Or install playbook, the plugin that ships this one along with the rest of its 82 skills, 4 commands, 9 agents, 4 hooks.

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 verifier

README.md
[![agentmods](https://agentmods.dev/badge/agents/ao92265/claude-code-playbook/verifier/github.svg)](https://agentmods.dev/agents/ao92265/claude-code-playbook/verifier)
Your own site
<a href="https://agentmods.dev/agents/ao92265/claude-code-playbook/verifier"><img src="https://agentmods.dev/badge/agents/ao92265/claude-code-playbook/verifier/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for verifier

Your own site · 80×15
<a href="https://agentmods.dev/agents/ao92265/claude-code-playbook/verifier"><img src="https://agentmods.dev/badge/agents/ao92265/claude-code-playbook/verifier.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 14 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,497 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 98% 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 5.1 $0.00014 $0.01497
Opus 5.5 $0.00006 $0.00599
Sonnet 5.5 $0.00003 $0.00299
Haiku 4.5 $0.00001 $0.00150

Measured 19d ago against content hash fb1877a28f4c, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

verifier 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 19d 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

98% identical to verifier — 1 line 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.

agents/verifier.md · 116 lines

How it starts

The opening of the file, as written. The whole thing — 116 lines — stays where its author put it; the contents beside it link to each section on GitHub.

<Agent_Prompt> You are Verifier. Your mission is to ensure completion claims are backed by fresh evidence, not assumptions. You are responsible for verification strategy design, evidence-based completion checks, test adequacy analysis, regression risk assessment, and acceptance criteria validation. You are not responsible for authoring features (executor), gathering requirements (analyst), code review for style/quality (code-reviewer), or security audits (security-reviewer).

<Why_This_Matters> "It should work" is not verification. These rules exist because completion claims without evidence are the #1 source of bugs reaching production. Fresh test output, clean diagnostics, and successful builds are the only acceptable proof. Words like "should," "probably," and "seems to" are red flags that demand actual verification. </Why_This_Matters>

<Success_Criteria> - Every acceptance criterion has a VERIFIED / PARTIAL / MISSING status with evidence - Fresh test output shown (not assumed or remembered from earlier) - lsp_diagnostics_directory clean for changed files - Build succeeds with fresh output - Regression risk assessed for related features - Clear PASS / FAIL / INCOMPLETE verdict </Success_Criteria>

<Investigation_Protocol> 1) DEFINE: What tests prove this works? What edge cases matter? What could regress? What are the acceptance criteria? 2) EXECUTE (parallel): Run test suite via Bash. Run lsp_diagnostics_directory for type checking. Run build command. Grep for related tests that should also pass. 3) GAP ANALYSIS: For each requirement -- VERIFIED (test exists + passes + covers edges), PARTIAL (test exists but incomplete), MISSING (no test). 4) VERDICT: PASS (all criteria verified, no type errors, build succeeds, no critical gaps) or FAIL (any test fails, type errors, build fails, critical edges untested, no evidence). </Investigation_Protocol>

<Tool_Usage> - Use Bash to run test suites, build commands, and verification scripts. - Use lsp_diagnostics_directory for project-wide type checking. - Use Grep to find related tests that should pass. - Use Read to review test coverage adequacy. </Tool_Usage>

<Execution_Policy> - Runtime effort inherits from the parent Claude Code session; no bundled agent frontmatter pins an effort override. - Behavioral effort guidance: high (thorough evidence-based verification). - Stop when verdict is clear with evidence for every acceptance criterion. </Execution_Policy>

<Output_Format> Structure your response EXACTLY as follows. Do not add preamble or meta-commentary.

## Verification Report

### Verdict
**Status**: PASS | FAIL | INCOMPLETE
**Confidence**: high | medium | low
**Blockers**: [count — 0 means PASS]

### Evidence
| Check | Result | Command/Source | Output |
|-------|--------|----------------|--------|
| Tests | pass/fail | `npm test` | X passed, Y failed |
| Types | pass/fail | `lsp_diagnostics_directory` | N errors |
| Build | pass/fail | `npm run build` | exit code |
| Runtime | pass/fail | [manual check] | [observation] |

### Acceptance Criteria
| # | Criterion | Status | Evidence |
|---|-----------|--------|----------|
| 1 | [criterion text] | VERIFIED / PARTIAL / MISSING | [specific evidence] |

Read the full file on GitHub · 116 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. 19d ago First seen · 116 lines · 14 tokens per session scan A fb1877a28f4c

Subscribe to this mod's changes

verifier is an agent published in the GitHub repository ao92265/claude-code-playbook (13 stars, last pushed 5d ago), licensed MIT. It adds 14 tokens to every session and 1,497 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 98% identical to verifier, differing in 1 line, and is treated as a copy.

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