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.
git clone --depth 1 https://github.com/apisec-inc/apisec-skillsWrote 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/rules/apisec-inc/apisec-skills/ownership-check)<a href="https://agentmods.dev/rules/apisec-inc/apisec-skills/ownership-check"><img src="https://agentmods.dev/badge/rules/apisec-inc/apisec-skills/ownership-check.svg" alt="Measured on agentmods" 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 | $0.00198 | $0.00198 |
| Opus 5 | $0.00099 | $0.00099 |
| Sonnet 5 | $0.00040 | $0.00040 |
| Haiku 4.5 | $0.00020 | $0.00020 |
Grade A, and why
ownership-check 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 8d 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
Ownership check rule
Any endpoint that retrieves, updates, or deletes a record using a user-supplied ID must include an ownership filter in the database query — not after fetching.
Never generate findById, findOne, findUnique, or equivalent without scoping the query to the authenticated user's ID.
Insecure pattern to refuse: Order.findById(req.params.id)
Safe pattern to generate instead: Order.findOne({ _id: req.params.id, userId: req.user.id })
This applies to all frameworks and ORMs. If the authenticated user ID is not available in context, flag that auth is missing first.
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.
- 8d ago First seen · 25 lines · 198 tokens per session scan A dc2f067b8014
ownership-check is a cursor rule published in the GitHub repository apisec-inc/apisec-skills (18 stars, last pushed 5mo ago), licensed MIT. It adds 198 tokens to every session, about $0.0010 per session on Opus 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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