verify

A verification command that runs an application's acceptance-test harness and explains the results. Acceptance criteria are the conditions a solution must satisfy for the work to count as complete.

In plain words
What is it for?
Checking challenges against a running application, testing web interfaces with Playwright, and explaining failed or skipped criteria.
Why use it?
It turns passing, failing and skipped checks into an explanation of what actually happened, including missing prerequisites and likely causes.

Command for Claude Code

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/micheltlutz/dev-challenge/verify
Clone the repo
git clone --depth 1 https://github.com/micheltlutz/dev-challenge

Made for: Claude Code.

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 483 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
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 $0.00011 $0.00483
Opus 5 $0.00005 $0.00242
Sonnet 5 $0.00002 $0.00097
Haiku 4.5 $0.00001 $0.00048

Measured 2d ago against content hash d1dd2068801f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

verify scanned grade A with 1 finding 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

allowed-tools: Read, Grep, Glob, Bash(python harness/cli.py:*), Bash(pytest harness/:*), Bash(curl:*)
.claude/commands/verify.md · 56 lines

What it actually says

Verify a solution against its acceptance criteria.

Work out the target

Default --base-url is http://localhost:8000. If $ARGUMENTS names a challenge or a URL, use those. If you do not know where their app is running, ask — do not guess and report a connection error as a failure.

python harness/cli.py --base-url <url> --challenge <id>

Omit --challenge to run everything.

For the web track the runner is Playwright:

cd harness/ui/web && BASE_URL=<their-frontend> npx playwright test

Explain the scorecard

Do not paste the raw output and stop. For each failing criterion:

  1. Quote the criterion — its ID and its Given/When/Then.
  2. State what actually happened.
  3. Point at the likely cause, in their code if you can see it.
  4. Ask what they think is going on, before giving the fix. Default posture is mentoring; see AGENTS.md.

For each skipped criterion, explain that a skip is not a pass and name the missing prerequisite:

Skip Meaning
"Could not register a user" backend-02-create-user is missing
"Could not authenticate" backend-03-login is missing
"Reference seed data not present" needs two users matching the fixture
"Cannot create statements" POST /statement/ is missing
"GET /users/me returned 404" the client cannot learn its own id

Ignore uncovered criteria unless they ask — those are UI or manual-review items the API harness cannot reach, not something they did wrong.

Close

One line on where they stand — "6 of 7, and the last one is the scoping rule" — and what to do next. If everything passes, say so without padding, and point at /next.

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 · 56 lines · 0 tokens per session scan A d1dd2068801f

Subscribe to this mod's changes

verify is a command published in the GitHub repository micheltlutz/dev-challenge (32 stars, last pushed 15d ago), licensed MIT. It adds 11 tokens to every session and 483 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.