Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add motlin/claude-code-plugins/plugin install codeWrote 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/motlin/claude-code-plugins/test-data)<a href="https://agentmods.dev/skills/motlin/claude-code-plugins/test-data"><img src="https://agentmods.dev/badge/skills/motlin/claude-code-plugins/test-data/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/motlin/claude-code-plugins/test-data"><img src="https://agentmods.dev/badge/skills/motlin/claude-code-plugins/test-data.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 | $0.00040 | $0.00368 |
| Opus 5.5 | $0.00016 | $0.00147 |
| Sonnet 5.5 | $0.00008 | $0.00074 |
| Haiku 4.5 | $0.00004 | $0.00037 |
Grade A, and why
test-data 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 22d 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 Data Guidelines
Literal values in tests must be recognizable as fabricated. A reader should never wonder whether a value was copied from production.
Timestamps
Use memorable boundary dates, not specific-looking times:
# Bad: looks recorded from a real system
2023-11-14T22:13:20.000Z
# Good
1999-12-31T00:00:00.000Z
2000-01-01T00:00:00.000Z
Names and identifiers
Use the Alice/Bob/Charlie series or obviously generic names, with example.com (reserved by RFC 2606) for email:
# Bad: could be a real person, or the developer's own identity
user: "jsmith"
email: "[email protected]"
# Good
user: "alice"
email: "[email protected]"
Numeric IDs
Use round numbers or boundary values, not arbitrary numbers that look like real database IDs:
# Bad
id: 8847291
# Good
id: 100
id: 0
id: 2_147_483_647
id: 9_999_999
Paths and URLs
No real usernames, home directories, or system paths:
# Bad
path: "/Users/jsmith/.config/app/settings.json"
# Good
path: "/tmp/test/settings.json"
url: "https://example.com/api/v1/resource"
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.
- 22d ago Changed · -11 lines · +7 tokens per session c1ecca95e552
- 1mo ago First seen · 75 lines · 33 tokens per session scan A 1096d3d537c9
test-data is a skill published in the GitHub repository motlin/claude-code-plugins (20 stars, last pushed yesterday), licensed Apache-2.0. It adds 40 tokens to every session and 368 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 2026-08-30.
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