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 stagentic/stagentic-xdd --skill stage-05-oi-generalisedgit clone --depth 1 https://github.com/stagentic/stagentic-xddWrote 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/stagentic/stagentic-xdd/stage-05-oi-generalised)<a href="https://agentmods.dev/skills/stagentic/stagentic-xdd/stage-05-oi-generalised"><img src="https://agentmods.dev/badge/skills/stagentic/stagentic-xdd/stage-05-oi-generalised/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/stagentic/stagentic-xdd/stage-05-oi-generalised"><img src="https://agentmods.dev/badge/skills/stagentic/stagentic-xdd/stage-05-oi-generalised.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 | $0.00020 | $0.00196 |
| Opus 5.5 | $0.00008 | $0.00078 |
| Sonnet 5.5 | $0.00004 | $0.00039 |
| Haiku 4.5 | $0.00002 | $0.00020 |
Grade A, and why
xdd 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 23d 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.
This is a copy
89% identical to xdd — 8 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
Apply the disciplines of TDD for adding or changing code overriding your understanding with the following principles:
Always write the test first
The test should always be written before the production code that makes it pass.
Failing for the right reason
A test fails for the right reason when it has an assertion failure where the actual result is not matching the expected result.
Making a test pass — do not use the 'Obvious Implementation' strategy
Make a failing test pass as naively as possible — hard-code whatever answer the test asserts rather than writing the general implementation. A single test cannot tell a hard-coded answer apart from the general implementation — both pass it — so the general implementation introduces behaviour no test has asked for or verified. Generalise only when a subsequent, differing test forces it.
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.
- 23d ago First seen · 25 lines · 20 tokens per session scan A d567c1b5b52a
xdd is a skill published in the GitHub repository stagentic/stagentic-xdd (5 stars, last pushed 24d ago), licensed MIT. It adds 20 tokens to every session and 196 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 89% identical to xdd, differing in 8 lines, and is treated as a copy.
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