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 fmflurry/settings-opencode --skill tddgit clone --depth 1 https://github.com/fmflurry/settings-opencodeWrote 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/fmflurry/settings-opencode/tdd)<a href="https://agentmods.dev/skills/fmflurry/settings-opencode/tdd"><img src="https://agentmods.dev/badge/skills/fmflurry/settings-opencode/tdd/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/fmflurry/settings-opencode/tdd"><img src="https://agentmods.dev/badge/skills/fmflurry/settings-opencode/tdd.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00000 | $0.03906 |
| Opus 5.5 | $0.00000 | $0.01562 |
| Sonnet 5.5 | $0.00000 | $0.00781 |
| Haiku 4.5 | $0.00000 | $0.00391 |
Grade A, and why
tdd 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.
How it starts
The opening of the file, as written. The whole thing — 247 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test-Driven Development — RED-GREEN-REFACTOR (mandatory baseline + optional ATDD outer loop)
The Core Mandate: RED-GREEN-REFACTOR
Features are built via strict TDD discipline: every behavior emerges via a failing test, minimal production code makes it green, then refactor while tests stay green. Tests and production code never change in the same commit. Hardcoding/faking is expected in the green step, then triangulated away during refactoring or by new tests.
This discipline applies to all layers: domain aggregates, Application handlers, Infrastructure implementations.
Optional: Double-Loop Method (ATDD Outer Loop)
For explicit use-case specification, you may adopt a two-loop structure: the outer loop turns a specification into acceptance tests at the handler level (Application layer); the inner loop builds domain behavior via strict RED-GREEN-REFACTOR. The outer loop helps document and test integration points; it is not mandatory.
OPTIONAL OUTER (ATDD): write the WHOLE shopping list of stub acceptance tests (all scenarios)
│
▼ then, one stub at a time:
flesh stub into real red test ──► create Application artifacts ──► still red
│
▼ domain behavior missing?
INNER (TDD): red ─► green ─► refactor (repeat)
│
▼
acceptance test goes green ─► refactor ─► next stub ─► … ─► done
MANDATORY (all features, all layers):
write test ─► compile shells ─► green code ─► refactor ──┐
└─► next behavior
Input: Specification
Before writing any test, a specification exists. It may come from:
- OpenSpec change spec (
openspec/changes/<change>/specs/<capability>/spec.md) with#### Scenario:WHEN/THEN blocks. - Product Owner work item (issue, backlog story, design doc) enumerating scenarios and examples.
- Finalized use-case documentation in
docs/usecases/<context>/(less common going forward; prefer OpenSpec).
What ships with it
1 file 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.
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 Changed · -2 lines f85cd92d261a
- 1mo ago First seen · 249 lines · 0 tokens per session scan A ddf2ac9ac245
tdd is a skill published in the GitHub repository fmflurry/settings-opencode (171 stars, last pushed 2d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 3,906 tokens. 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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