google/mantis is a modular set of security-review skills that coding agents use to find, reproduce, and patch software vulnerabilities. It is for adapting automated security testing to application, infrastructure, machine-learning, hardware, and firmware projects, with expert review required for results. The catalogue skills and instruction provide the workflow for using Mantis with coding agents.
Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/google/mantisnpx agentmods add skills/google/mantis/mantis-researcherWrote 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/google/mantis/mantis-researcher)<a href="https://agentmods.dev/skills/google/mantis/mantis-researcher"><img src="https://agentmods.dev/badge/skills/google/mantis/mantis-researcher/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/google/mantis/mantis-researcher"><img src="https://agentmods.dev/badge/skills/google/mantis/mantis-researcher.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 | $0.00057 | $0.06057 |
| Opus 5.5 | $0.00023 | $0.02423 |
| Sonnet 5.5 | $0.00011 | $0.01211 |
| Haiku 4.5 | $0.00006 | $0.00606 |
Grade A, and why
mantis-researcher 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 1mo 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 — 430 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mantis Researcher (/mantis-researcher)
System Goal
Resilience Code Auditor. Performs rapid triage and deep-dive reviews of source files to identify boundary checks, preconditions, missing sanitization, and interface violations.
Command Definition
- Command:
/mantis-researcher - Description: Audits production source code files based on the strategy in
workspace/plan.json. - Arguments (optional; supplied by the orchestrator, consumed by Block A):
--snapshot_root/SNAPSHOT_ROOT: absolute path to the pinned, read-only code snapshot for this pass. This is the CODE_ROOT that all snapshot-relative path fields resolve against (Block A step 1b).--snapshot_id/SNAPSHOT_ID: the pass snapshot identifier. Used for the sentinel check (Block A step 2) and stamped verbatim into every finding'sdiscovery_commit.--state_root: absolute path to theworkspace/state directory (plan.json,.mantis_state.json,findings/,kb/). State paths are STATE-RELATIVE and are NEVER prefixed with CODE_ROOT (Block A step 3).--target_root(authoritative override, Block A step 1a) is also honored if supplied.- All flags absent -> DEGRADED/legacy mode: CODE_ROOT falls back to the
current directory,
snapshot_pinnedis treated as false, and behavior matches today's exactly (nodiscovery_commitis written).
Input/Output Contract
- Reads:
workspace/plan.json(falls back to codebase sweep if missing/empty).workspace/.mantis_state.json(to track current loop pass).- referenced Markdown files in
"kb_references"(e.g.workspace/kb/entities/*.md). - Target source code files.
workspace/kb/structural_index/manifest.json(to check structural index availability/status).workspace/helpers/query_structural_index.py(to invoke bounded structural-index queries).
- Writes:
- Raw finding files to
workspace/findings/<uuid>.json(createsworkspace/findings/if missing).
- Raw finding files to
- Preconditions:
- Target files must be accessible.
- Idempotency Guarantee:
- Writes new findings as separate files with unique UUIDs. Rely on
mantis-dedupeto cluster and merge duplicate findings on subsequent steps.
- Writes new findings as separate files with unique UUIDs. Rely on
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.
- 1mo ago First seen · 430 lines · 57 tokens per session scan A 3f8203e26347
mantis-researcher is a skill published in the GitHub repository google/mantis (2,474 stars, last pushed today), licensed Apache-2.0. It adds 57 tokens to every session and 6,057 once invoked, about $0.0002 per session on Opus 5.5. 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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query-performance-safety
A code-review guide for database access and recursive processing. It applies when code makes queries inside loops, fetches many IDs, uses IN clauses, or nests service calls.
storage-url-safety
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