Borrowing it
Nothing to install: this file belongs to LAA-Software-Engineering/terfyn. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/LAA-Software-Engineering/terfyn/main/.cursor/skills/feature/SKILL.mdgit clone --depth 1 https://github.com/LAA-Software-Engineering/terfynWrote 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/laa-software-engineering/terfyn/feature)<a href="https://agentmods.dev/skills/laa-software-engineering/terfyn/feature"><img src="https://agentmods.dev/badge/skills/laa-software-engineering/terfyn/feature/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.
<a href="https://agentmods.dev/skills/laa-software-engineering/terfyn/feature"><img src="https://agentmods.dev/badge/skills/laa-software-engineering/terfyn/feature.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00039 | $0.00353 |
| Opus 5.5 | $0.00016 | $0.00141 |
| Sonnet 5.5 | $0.00008 | $0.00071 |
| Haiku 4.5 | $0.00004 | $0.00035 |
Grade A, and why
feature 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 1mo 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
Feature
Workflow
- Clarify scope — Read
docs/DESIGN_DOC.mdand nearby code before coding. Prefer the smallest change that meets the ask. - Implement — Match patterns in the same package (
cmd/terfyn,internal/*). Avoid unrelated refactors. - Tests — Add or update unit/integration coverage. For intentional CLI output changes:
GO_UPDATE_GOLDEN=1 go test ./internal/cli/... -run TestGolden_ - Verify — Run
make ci(verify-fmt, vet, test). Fix failures before claiming done. - Changelog — If user-visible or breaking, add an entry under Unreleased in
CHANGELOG.md. - Pull request — When opening a PR, read
.github/PULL_REQUEST_TEMPLATE.mdand use that exact structure for the body (HEREDOC withgh pr create). Fill Summary, Test plan, and Checklist. Do not invent a different format.
Layout reminders
| Area | Path |
|---|---|
| CLI entry | cmd/terfyn |
| Commands / goldens | internal/cli |
| Spec / project load | internal/spec, internal/project |
| Plan / apply / engine / policy | internal/plan, internal/apply, internal/engine, internal/policy |
| E2E | test/integration |
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.
- 1mo ago First seen · 27 lines · 39 tokens per session scan A af1ac2653702
feature is a skill published in the GitHub repository LAA-Software-Engineering/terfyn (4 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 39 tokens to every session and 353 once invoked, about $0.0002 per session on Opus 5.5. 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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example-time-skill
Teaches the agent to format all times as ISO-8601 UTC with an explicit timezone label.
using-superpowers
Use when starting any conversation - establishes how to find and use skills, requiring Skill tool invocation before ANY response including clarifying questions.
wttr-weather
Weather via wttr.in GET (no key). Use for weather/forecast; prefer os.http.request.
jk
Manage Jenkins controllers with jk, including jobs, runs, logs, artifacts, credentials, nodes, queues, and plugins.
engineering-principles
Practical engineering judgement: smallest change, subtract before adding, data structures before logic, idempotent operations, migrate callers then delete. Use when designing, building, or reviewing changes.
financial-analysis
Financial figures done carefully: periods and fiscal calendars, units and currencies, reconciliation, magnitude sanity checks, sourced assumptions. Use for statements, budgets, pricing, and diligence numbers.