semgrep

semgrep is a skill for Claude Code, Codex from FlorianBruniaux/starmapper. It costs 95 tokens per session (2,353 once invoked), scanned A, original, no licence file.

A code scanner that runs Semgrep, a rule-based tool for finding security problems in source code. It can run broad checks or focus on important, high-confidence vulnerabilities, using cross-file data tracking when available.

In plain words
What is it for?
Scanning a codebase, running full or focused security checks, detecting programming languages, and finding vulnerabilities across files when supported.
Why use it?
Manual code review may miss repeated security patterns across a codebase. Automated Semgrep checks help locate those patterns and report them consistently.

Skill for Claude CodeCodex

Part of the static-analysis plugin — 3 skills, 1 agent shipped together

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.

agentmods
npx agentmods add skills/florianbruniaux/starmapper/semgrep
Any agent
npx skills add FlorianBruniaux/starmapper --skill semgrep
Clone the repo
git clone --depth 1 https://github.com/FlorianBruniaux/starmapper

Made for: Claude Code, Codex.

Or install static-analysis, the plugin that ships this one along with the rest of its 3 skills, 1 agent.

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

README.md
[![agentmods](https://agentmods.dev/badge/skills/florianbruniaux/starmapper/semgrep.svg)](https://agentmods.dev/skills/florianbruniaux/starmapper/semgrep)
Your own site
<a href="https://agentmods.dev/skills/florianbruniaux/starmapper/semgrep"><img src="https://agentmods.dev/badge/skills/florianbruniaux/starmapper/semgrep.svg" alt="Measured on agentmods" height="20"></a>
Per session 95 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,353 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00095 $0.02353
Opus 5 $0.00048 $0.01177
Sonnet 5 $0.00019 $0.00471
Haiku 4.5 $0.00010 $0.00235

Measured 5d ago against content hash b12e2130745f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

semgrep 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 5d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/merge_sarif.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

.claude/plugins/static-analysis/skills/semgrep/SKILL.md · 213 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

5 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. 5d ago First seen · 213 lines · 95 tokens per session scan A b12e2130745f

Subscribe to this mod's changes

semgrep is a skill published in the GitHub repository FlorianBruniaux/starmapper (83 stars, last pushed 3d ago), with no licence file. It adds 95 tokens to every session and 2,353 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 2026-08-30.

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