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 skills add lfyxhappy/lfcode --skill test-fixture-designergit clone --depth 1 https://github.com/lfyxhappy/lfcodeWrote 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/lfyxhappy/lfcode/test-fixture-designer)<a href="https://agentmods.dev/skills/lfyxhappy/lfcode/test-fixture-designer"><img src="https://agentmods.dev/badge/skills/lfyxhappy/lfcode/test-fixture-designer/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/lfyxhappy/lfcode/test-fixture-designer"><img src="https://agentmods.dev/badge/skills/lfyxhappy/lfcode/test-fixture-designer.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 | $0.00060 | $0.00357 |
| Opus 5.5 | $0.00024 | $0.00143 |
| Sonnet 5.5 | $0.00012 | $0.00071 |
| Haiku 4.5 | $0.00006 | $0.00036 |
Grade A, and why
test-fixture-designer 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
Test Fixture Designer
Create test data and environments that reveal behavior instead of hiding it.
Workflow
- Read repository instructions, test framework conventions, target behavior, schemas, existing fixtures, and cleanup helpers.
- Identify the smallest valid data shape, defaults that matter, invalid variants, ownership boundaries, and the relationship between fixture data and assertions.
- Prefer named builders or factories when variation is recurring; keep a literal fixture inline when it is clearer and single-use.
- Make important values explicit, allow each test to override only the values it needs, and avoid opaque random data unless a seed is recorded.
- Use isolated temporary resources and deterministic identifiers. Ensure teardown removes only resources created by that test and remains safe after partial setup.
- Run the focused test repeatedly when lifecycle or isolation is at risk, then inspect for data leakage, order dependence, and hidden shared state.
Boundaries
- Keep fixture review and design read-only unless the user asks to modify tests or test infrastructure.
- Do not copy production records, credentials, personal data, or large unreviewed dumps into fixtures.
- Do not make fixtures so broad that unrelated changes silently pass assertions.
- Do not delete shared files, databases, queues, or cloud resources during cleanup without explicit authorization and verified ownership.
Completion Check
Report fixture ownership, override points, isolation and cleanup behavior, data intentionally omitted, verification commands, and any remaining shared-state risk.
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 · 29 lines · 60 tokens per session scan A 20c074f9401d
test-fixture-designer is a skill published in the GitHub repository lfyxhappy/lfcode (2 stars, last pushed 1mo ago), licensed MIT. It adds 60 tokens to every session and 357 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 2026-09-05.
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