semgrep-rule-creator

semgrep-rule-creator is a skill for Claude Code, Codex from ASK191225/bugbounty-kit. It costs 37 tokens per session (1,729 once invoked), scanned A, original, no licence file.

A tool for creating Semgrep rules. Semgrep is a code-scanning tool that searches source code for security problems, bugs, and other patterns.

In plain words
What is it for?
Use it to write custom checks for vulnerabilities, bug patterns, and other code patterns.
Why use it?
It helps turn a security concern or repeated code mistake into a check that can find matching code automatically.

Skill for Claude CodeCodex

Written for Claude Code and Codex: allowed-tools in frontmatter, but also agents/openai.yaml present.

Good fit Use it to write custom checks for vulnerabilities, bug patterns, and other code patterns.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/ask191225/bugbounty-kit/semgrep-rule-creator
Install

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.

Any agent
npx skills add ASK191225/bugbounty-kit --skill semgrep-rule-creator
Clone the repo
git clone --depth 1 https://github.com/ASK191225/bugbounty-kit

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for semgrep-rule-creator

README.md
[![agentmods](https://agentmods.dev/badge/skills/ask191225/bugbounty-kit/semgrep-rule-creator.svg)](https://agentmods.dev/skills/ask191225/bugbounty-kit/semgrep-rule-creator)
Your own site
<a href="https://agentmods.dev/skills/ask191225/bugbounty-kit/semgrep-rule-creator"><img src="https://agentmods.dev/badge/skills/ask191225/bugbounty-kit/semgrep-rule-creator.svg" alt="Measured on agentmods" height="20"></a>
Per session 37 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,729 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00037 $0.01729
Opus 5 $0.00018 $0.00864
Sonnet 5 $0.00007 $0.00346
Haiku 4.5 $0.00004 $0.00173

Measured 7d ago against content hash 82093e2a5d69, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

semgrep-rule-creator 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 7d 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.

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

pattern: os.system("rm " + $VAR)
skills/semgrep-rule-creator/SKILL.md · 166 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

Files

What ships with it

4 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.

Changes

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.

  1. 7d ago First seen · 166 lines · 37 tokens per session scan A 82093e2a5d69

Subscribe to this mod's changes

semgrep-rule-creator is a skill published in the GitHub repository ASK191225/bugbounty-kit (3 stars, last pushed 1mo ago), with no licence file. It adds 37 tokens to every session and 1,729 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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