cambridge-beer-festival-app: Skill for Claude Code

.claude/skills/diagnostics-and-tooling/SKILL.md

diagnostics-and-tooling is a skill for Claude Code from richardthe3rd/cambridge-beer-festival-app. It costs 217 tokens per session (7,389 once invoked), scanned A, original, MIT.

A measurement guide for diagnosing the Cambridge Beer Festival app. It explains how to run Flutter tests and code analysis, inspect their logs, decode web crash reports, and read code-coverage data.

In plain words
What is it for?
Use it to investigate failed tests, analysis warnings, minified Flutter-web crashes, and which parts of the code are covered by tests.
Why use it?
It replaces guesses based on what the app looks like with recorded test results, warnings, errors, crash details, and coverage measurements.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: reads .claude/ paths; mentions Claude Code; mentions AGENTS.md.

This is richardthe3rd/cambridge-beer-festival-app's own configuration. It tells Claude Code how to work on cambridge-beer-festival-app 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 cambridge-beer-festival-app configures →

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is ./bin/mise run test test/domain/services/drink_filter_service_test.dart.

Reuse

Borrowing it

Nothing to install: this file belongs to richardthe3rd/cambridge-beer-festival-app. 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/richardthe3rd/cambridge-beer-festival-app/main/.claude/skills/diagnostics-and-tooling/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/richardthe3rd/cambridge-beer-festival-app

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 diagnostics-and-tooling

README.md
[![agentmods](https://agentmods.dev/badge/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling/github.svg)](https://agentmods.dev/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling)
Your own site
<a href="https://agentmods.dev/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling"><img src="https://agentmods.dev/badge/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling/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 diagnostics-and-tooling

Your own site · 80×15
<a href="https://agentmods.dev/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling"><img src="https://agentmods.dev/badge/skills/richardthe3rd/cambridge-beer-festival-app/diagnostics-and-tooling.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 217 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 7,389 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 $0.00217 $0.07389
Opus 5 $0.00109 $0.03694
Sonnet 5 $0.00043 $0.01478
Haiku 4.5 $0.00022 $0.00739

Measured 12d ago against content hash f998acb34c71, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

diagnostics-and-tooling 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 12d ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/decode-stack.mjs, scripts/lcov-summary.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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/skills/diagnostics-and-tooling/SKILL.md · 582 lines

How it starts

The opening of the file, as written. The whole thing — 582 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Diagnostics and Tooling

Every fact below was re-verified against the working tree on 2026-07-02 (see Provenance). If a command's output disagrees with what's written here, trust the command — then fix this file.

Theme: run the measurement tool once, read its output carefully, and interpret it correctly. Don't guess at "it's probably fine" or "that looks like the bug" — grep the log, decode the stack, read the coverage line.


1. Test / analyze log workflow

./bin/mise run test [path] and ./bin/mise run analyze [path] are thin wrappers (mise-tasks/test.sh, mise-tasks/analyze.sh) around flutter test / flutter analyze. Both:

  1. Print a log path FIRST, before running anything: TEST_LOG=/tmp/test-XXXXXX.log or ANALYZE_LOG=/tmp/analyze-XXXXXX.log (mktemp-generated).
  2. Stream output through tee into that file, filtering two noise lines (Woah! You appear|superuser privileges — root-user warnings irrelevant here).
  3. Preserve the real exit code via ${PIPESTATUS[0]} (the tee would otherwise mask a non-zero flutter exit).
  4. Print a ready-to-use grep command at the end:
    • test: grep -n 'FAILED\|ERROR' $TEST_LOG
    • analyze: grep -n 'error\|warning' $ANALYZE_LOG

Run once, grep many times. Do not re-run the whole suite to look for a different string — the log file already has everything.

./bin/mise run test test/domain/services/drink_filter_service_test.dart
# TEST_LOG=/tmp/test-AbCdEf.log
grep -n 'FAILED\|ERROR' /tmp/test-AbCdEf.log
grep -n 'preference_keys' /tmp/test-AbCdEf.log   # any other query, same log

Stable paths across multiple runs

Override the mktemp path with the env var so repeated runs land in one place you can diff:

TEST_LOG=/tmp/my-run.log ./bin/mise run test
ANALYZE_LOG=/tmp/my-analyze.log ./bin/mise run analyze lib/screens/

What good/bad output looks like

  • test: flutter test prints one line per test group in MM:SS +N: <name> form, ending All tests passed! (good) or Some tests failed. with FAILED markers and stack traces above the summary (grep target: FAILED\|ERROR). Verified live: 00:02 +2: All tests passed!.
  • analyze: Analyzing <paths>... then either No issues found! (ran in N.Ns) (good — verified live against lib/utils/ and lib/constants/), or one line per finding, bullet-separated: info • <message> • <file>:<line>:<col> • <lint_rule_name> (severity is info, warning, or error; since #524 the task runs without --no-fatal-infos, so every severity fails it).

Read the full file on GitHub · 582 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 12d ago First seen · 582 lines · 217 tokens per session scan A f998acb34c71

Subscribe to this mod's changes

diagnostics-and-tooling is a skill published in the GitHub repository richardthe3rd/cambridge-beer-festival-app (2 stars, last pushed yesterday), licensed MIT. It adds 217 tokens to every session and 7,389 once invoked, about $0.0011 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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