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.
npx agentmods add skills/matteing/opal/lint-and-formatnpx skills add matteing/opal --skill lint-and-formatgit clone --depth 1 https://github.com/matteing/opalWrote 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.
[](https://agentmods.dev/skills/matteing/opal/lint-and-format)<a href="https://agentmods.dev/skills/matteing/opal/lint-and-format"><img src="https://agentmods.dev/badge/skills/matteing/opal/lint-and-format.svg" alt="Measured on agentmods" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00036 | $0.00443 |
| Opus 5 | $0.00018 | $0.00221 |
| Sonnet 5 | $0.00007 | $0.00089 |
| Haiku 4.5 | $0.00004 | $0.00044 |
Grade A, and why
lint-and-format 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 4d 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.
What it actually says
Lint & Format Skill
You ensure all code passes the project's linters and formatters before it gets committed. This mirrors the lefthook pre-commit hooks and CI checks so problems are caught immediately.
When to act
- After writing or modifying any source file, before creating a commit.
- When the user asks to fix lint or formatting issues.
- When a commit or CI fails due to formatting.
Commands
Elixir (lib/, test/, config/)
# Check formatting (what CI runs)
mise run lint:core
# Auto-fix formatting
mise run format:core
TypeScript/JavaScript (cli/)
# ESLint check
cd cli && pnpm lint
# ESLint auto-fix
cd cli && pnpm lint:fix
# Prettier check
cd cli && pnpm format:check
# Prettier auto-fix
cd cli && pnpm format
Run everything
# Check all (what CI runs)
mise run lint
# Fix all
mise run format
Workflow
- After making code changes, run the relevant lint/format check commands.
- If there are failures, auto-fix them using the fix variants.
- If auto-fix changes files, review the diff to make sure nothing unexpected changed.
- Only then proceed with staging and committing.
Rules
- Never commit code that fails linting or formatting checks.
- Prefer auto-fix (
mise run format,lint:fix) over manual edits when possible. - If a lint rule seems wrong for a specific case, discuss with the user before adding a suppression comment.
- Do not disable or weaken lint rules without explicit approval.
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.
- 4d ago First seen · 68 lines · 36 tokens per session scan A 6e44cac64906
lint-and-format is a skill published in the GitHub repository matteing/opal (59 stars, last pushed 22d ago), licensed MIT. It adds 36 tokens to every session and 443 once invoked, about $0.0002 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 2026-08-30.
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