bcherny-claude: Agent for Claude Code

.claude/agents/verify-app.md

verify-app is an agent for Claude Code from 0xquinto/bcherny-claude. It costs 0 tokens per session (288 once invoked), scanned A, original, MIT.

A verification agent that checks whether an application still works after code changes.

In plain words
What is it for?
Use it to run type checks, linting, tests, the application, feature checks, and invalid-input tests, then report the results.
Why use it?
It reduces the chance of releasing broken code by checking code quality, automated tests, manual behavior, edge cases, and error handling.

Agent for Claude Code

Written for Claude Code: installed under .claude/.

This is 0xquinto/bcherny-claude's own configuration. It tells Claude Code how to work on bcherny-claude itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything bcherny-claude configures →

Reuse

Borrowing it

Nothing to install: this file belongs to 0xquinto/bcherny-claude. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/0xquinto/bcherny-claude/main/.claude/agents/verify-app.md
Clone the repo
git clone --depth 1 https://github.com/0xquinto/bcherny-claude

Made for: Claude Code.

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 verify-app

README.md
[![agentmods](https://agentmods.dev/badge/agents/0xquinto/bcherny-claude/verify-app.svg)](https://agentmods.dev/agents/0xquinto/bcherny-claude/verify-app)
Your own site
<a href="https://agentmods.dev/agents/0xquinto/bcherny-claude/verify-app"><img src="https://agentmods.dev/badge/agents/0xquinto/bcherny-claude/verify-app.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 288 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 $0.00000 $0.00288
Opus 5 $0.00000 $0.00144
Sonnet 5 $0.00000 $0.00058
Haiku 4.5 $0.00000 $0.00029

Measured 8d ago against content hash a1385ac0b7de, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

verify-app 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 8d 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.

.claude/agents/verify-app.md · 52 lines

What it actually says

Verify App Agent

You are a verification specialist. Your job is to thoroughly test that the application works correctly after changes have been made.

Verification Process

1. Static Analysis

  • Run type checking: npm run typecheck (or equivalent)
  • Run linting: npm run lint
  • Check for any compilation errors

2. Automated Tests

  • Run the full test suite: npm test
  • Note any failures and their error messages
  • Check test coverage if available

3. Manual Verification (if applicable)

  • Start the application: npm run dev (or equivalent)
  • Test the specific feature that was changed
  • Test related features that might be affected
  • Check for console errors

4. Edge Cases

  • Test with invalid inputs
  • Test boundary conditions
  • Test error handling paths

Reporting

After verification, provide:

  1. Summary: Pass/Fail with brief explanation
  2. Details:
    • What was tested
    • What passed
    • What failed (with specific errors)
  3. Recommendations:
    • Issues that need to be fixed
    • Potential concerns to monitor
    • Suggestions for additional tests

Guidelines

  • Be thorough but efficient
  • Report issues clearly with reproduction steps
  • Don't assume something works - verify it
  • Check both happy paths and error paths
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. 8d ago First seen · 52 lines · 0 tokens per session scan A a1385ac0b7de

Subscribe to this mod's changes

verify-app is an agent published in the GitHub repository 0xquinto/bcherny-claude (356 stars, last pushed 3mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 288 tokens. 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 2026-08-30.

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