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 HigorAlves/orc --skill tddgit clone --depth 1 https://github.com/HigorAlves/orcWrote 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/higoralves/orc/tdd)<a href="https://agentmods.dev/skills/higoralves/orc/tdd"><img src="https://agentmods.dev/badge/skills/higoralves/orc/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/higoralves/orc/tdd"><img src="https://agentmods.dev/badge/skills/higoralves/orc/tdd.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 | $0.00013 | $0.01238 |
| Opus 5.5 | $0.00005 | $0.00495 |
| Sonnet 5.5 | $0.00003 | $0.00248 |
| Haiku 4.5 | $0.00001 | $0.00124 |
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 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.
How it starts
The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test-Driven Development
TDD is the red → green → refactor loop. This skill is the reference that makes that loop produce tests worth keeping: what a good test is, where tests go, the named anti-patterns, and the rules of the loop. This is orc iron rule #2 — the failing test comes before the production code, every cycle.
When exploring the codebase, use the project's domain glossary (and GLOSSARY.md if it exists) so test names and interface vocabulary match the project's language, and respect ADRs in the area you're touching.
What a good test is
Tests verify behavior through public interfaces, not implementation details. Code can change entirely; tests shouldn't. A good test reads like a specification — "user can checkout with valid cart" tells you exactly what capability exists — and survives refactors because it doesn't care about internal structure.
See references/tests.md for good/bad examples and references/mocking.md for mocking guidelines.
Seams — where tests go
A seam is the public boundary you test at: the interface where you observe behavior without reaching inside.
Test only at pre-agreed seams. Before writing any test, write down the seams under test and confirm them with the user. No test is written at an unconfirmed seam. You can't test everything — agreeing the seams up front is how testing effort lands on critical paths and complex logic instead of every possible edge case.
Ask: "What should the public interface look like, and which seams should we test?" Give each proposed seam a one-line note on what it catches and what it misses — the user is choosing where testing effort lands, so show them the trade.
When the shape of the interface is itself in question — how deep the module is, where the seam belongs — consult orc:codebase-design for the module/interface/depth/seam vocabulary, plus references/deep-modules.md (small interface, deep implementation) and references/interface-design.md (designing for testability).
What ships with it
5 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.
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 Changed · +1 lines · -23 tokens per session 53340e53a1cf
- 1mo ago First seen · 86 lines · 36 tokens per session scan A 9d50bf3e2a9b
tdd is a skill published in the GitHub repository HigorAlves/orc (7 stars, last pushed yesterday), licensed MIT. It adds 13 tokens to every session and 1,238 once invoked, about $0.0001 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 2026-09-03.
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