mantis-history

mantis-history is a skill for Claude Code, Codex from google/mantis. It costs 76 tokens per session (2,952 once invoked), scanned A, original, Apache-2.0.

A security-analysis step that studies version-control history, the record of past code changes, to find earlier vulnerabilities and security fixes.

In plain words
What is it for?
Use it before later security stages to create historical findings and lessons from commits, diffs, and repository structure.
Why use it?
Past fixes and recurring problem patterns can reveal risks that a review of the current code alone may miss.

Skill for Claude CodeCodex

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/google/mantis/mantis-history
Any agent
npx skills add google/mantis --skill mantis-history
Clone the repo
git clone --depth 1 https://github.com/google/mantis

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 mantis-history

README.md
[![agentmods](https://agentmods.dev/badge/skills/google/mantis/mantis-history.svg)](https://agentmods.dev/skills/google/mantis/mantis-history)
Your own site
<a href="https://agentmods.dev/skills/google/mantis/mantis-history"><img src="https://agentmods.dev/badge/skills/google/mantis/mantis-history.svg" alt="Measured on agentmods" height="20"></a>
Per session 76 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,952 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00076 $0.02952
Opus 5 $0.00038 $0.01476
Sonnet 5 $0.00015 $0.00590
Haiku 4.5 $0.00008 $0.00295

Measured 4d ago against content hash ef777063f09b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mantis-history 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 4d 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.

mantis-history/SKILL.md · 240 lines

How it starts

The opening of the file, as written. The whole thing — 240 lines — stays where its author put it; the contents beside it link to each section on GitHub.

History Analyzer (/mantis-history)

System Goal

Historical Vulnerability Extractor. Analyzes repository's version control system (VCS) history to extract past vulnerabilities, security-related fixes, patches, and associated files, creating a historical learnings database to inform downstream skills.

Command Definition

  • Command: /mantis-history
  • Description: Analyzes repository's version control system (VCS) history to extract past vulnerabilities and fixes, producing a structured historical learnings file (workspace/historical_learnings.jsonl).
  • Arguments (optional; supplied by the orchestrator, consumed by Block A): --snapshot_root/--snapshot_id/--state_root. History reads VCS logs from the LIVE repository root (Block A step 5), not the snapshot; it uses --state_root only to place its cache/output/script. All absent -> DEGRADED (behaves as today, live cwd).

Input/Output Contract

  • Reads:
    • workspace/.mantis_state.json (to track current loop pass).
    • Codebase directory structure and key files (to determine stack).
    • VCS history logs (commit messages, titles, diffs).
    • mantis-summary.md (optional, if available).
    • Internal history analysis cache (optional, if exists).
  • Writes:
    • VCS extraction script (written on-the-fly to workspace).
    • workspace/historical_learnings.jsonl.
    • Internal history analysis cache.
    • All under --state_root/workspace/ (cache, historical_learnings.jsonl, extraction script): kept outside the target tree. Optional history_status marker (UNSUPPORTED_VCS / PARTIAL_SHALLOW).
  • Preconditions:
    • Target repository and VCS logs must be accessible.
  • Idempotency Guarantee:
    • The cache is the source of truth: the output DB is rebuilt from it every run and is never truncated to empty while the cache is non-empty. The cache is invalidated on VCS-history rewrite (_analyzed_head no longer reachable) or a vcs_type/repo-identity change. On none/unknown VCS the stage writes an empty DB + history_status=UNSUPPORTED_VCS and exits.

Read the full file on GitHub · 240 lines

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. 4d ago First seen · 240 lines · 76 tokens per session scan A ef777063f09b

Subscribe to this mod's changes

mantis-history is a skill published in the GitHub repository google/mantis (853 stars, last pushed 6d ago), licensed Apache-2.0. It adds 76 tokens to every session and 2,952 once invoked, about $0.0004 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.