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 balsm-health/Balsm-AI --skill exploiting-mass-assignment-in-rest-apisgit clone --depth 1 https://github.com/balsm-health/Balsm-AIWrote 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/balsm-health/balsm-ai/exploiting-mass-assignment-in-rest-apis)<a href="https://agentmods.dev/skills/balsm-health/balsm-ai/exploiting-mass-assignment-in-rest-apis"><img src="https://agentmods.dev/badge/skills/balsm-health/balsm-ai/exploiting-mass-assignment-in-rest-apis/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/balsm-health/balsm-ai/exploiting-mass-assignment-in-rest-apis"><img src="https://agentmods.dev/badge/skills/balsm-health/balsm-ai/exploiting-mass-assignment-in-rest-apis.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 | $0.00041 | $0.02206 |
| Opus 5 | $0.00020 | $0.01103 |
| Sonnet 5 | $0.00008 | $0.00441 |
| Haiku 4.5 | $0.00004 | $0.00221 |
Grade A, and why
exploiting-mass-assignment-in-rest-apis scanned grade A with 1 finding 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 12d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -H "Authorization: Bearer USER_TOKEN" http://target.com/api/users/me | jq . The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
What ships with it
3 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.
- 12d ago First seen · 239 lines · 41 tokens per session scan A 23393f7b1470
exploiting-mass-assignment-in-rest-apis is a skill published in the GitHub repository balsm-health/Balsm-AI (2 stars, last pushed 1mo ago), with no licence file. It adds 41 tokens to every session and 2,206 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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