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 EresusSecurity/appsec-skills --skill eresus-pr-security-reviewgit clone --depth 1 https://github.com/EresusSecurity/appsec-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/skills/eresussecurity/appsec-skills/eresus-pr-security-review)<a href="https://agentmods.dev/skills/eresussecurity/appsec-skills/eresus-pr-security-review"><img src="https://agentmods.dev/badge/skills/eresussecurity/appsec-skills/eresus-pr-security-review/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/eresussecurity/appsec-skills/eresus-pr-security-review"><img src="https://agentmods.dev/badge/skills/eresussecurity/appsec-skills/eresus-pr-security-review.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 | $0.00090 | $0.00871 |
| Opus 5 | $0.00045 | $0.00436 |
| Sonnet 5 | $0.00018 | $0.00174 |
| Haiku 4.5 | $0.00009 | $0.00087 |
Grade A, and why
eresus-pr-security-review 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 11d 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 — 130 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Security PR Review
Purpose
Review changed code with a security-review mindset: prioritize introduced bugs, exploitable regressions, and missing coverage in the modified attack surface. Focus on what the diff changes, not on writing a general audit of the whole repository.
Scope Rules
- Prioritize vulnerabilities introduced or exposed by the diff.
- Inspect surrounding code when needed to confirm reachability, auth context, or sanitizer behavior.
- Mention pre-existing issues only when the change makes them reachable, worse, or security-relevant now.
- Findings come first; summary is secondary.
Workflow
Step 1: Read the Diff as an Attack Surface Change
Identify:
- newly added endpoints, handlers, controllers, jobs, or CLI paths
- changed authorization checks or middleware wiring
- new deserialization, template rendering, file, network, or command execution paths
- config changes that weaken defaults or widen trust boundaries
Step 2: Map New Sources, Sinks, and Guards
For changed code, locate:
- attacker-controlled inputs
- dangerous sinks
- sanitization, validation, auth, and feature-flag guards
Do not stop at the edited hunk if the actual sink or protection lives nearby.
Step 3: Trace Security-Sensitive Data Flow
Apply lightweight taint reasoning through:
- helper calls
- serializers and DTOs
- middleware layers
- ORM/query helpers
- template/view rendering
- background job enqueue/dequeue boundaries
Step 4: Review Diff-Specific Risk Patterns
Pay extra attention to:
- string-built queries, filters, or shell commands
- unsafe deserialization, polymorphic typing, object revival, or parser feature flags
- auth checks moved later in the flow
- newly trusted headers, cookies, or client-supplied role fields
- open redirects added through
next,returnTo, orredirect_url - debug logging of secrets, tokens, or PII
- upload handling, archive extraction, or path joins
- new outbound HTTP fetches or webhook callbacks
- security settings changed from strict to permissive
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.
- 11d ago First seen · 130 lines · 90 tokens per session scan A b992b9760487
eresus-pr-security-review is a skill published in the GitHub repository EresusSecurity/appsec-skills (7 stars, last pushed 5mo ago), licensed Apache-2.0. It adds 90 tokens to every session and 871 once invoked, about $0.0005 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 2026-08-31.
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