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 fusengine/agents --skill sniper-checkgit clone --depth 1 https://github.com/fusengine/agentsWrote 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/fusengine/agents/sniper-check)<a href="https://agentmods.dev/skills/fusengine/agents/sniper-check"><img src="https://agentmods.dev/badge/skills/fusengine/agents/sniper-check/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/fusengine/agents/sniper-check"><img src="https://agentmods.dev/badge/skills/fusengine/agents/sniper-check.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- 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 | $0.00026 | $0.00625 |
| Opus 5.5 | $0.00010 | $0.00250 |
| Sonnet 5.5 | $0.00005 | $0.00125 |
| Haiku 4.5 | $0.00003 | $0.00063 |
Grade A, and why
sniper-check 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 — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Target: $ARGUMENTS
Sniper Check
Overview
Quick code quality validation using the sniper agent in an isolated forked context. Executes the full 6-phase workflow without polluting the main conversation context.
| Feature | Detail |
|---|---|
| Context | Forked (isolated sub-agent) |
| Agent | sniper (Sonnet) |
| Phases | 6-phase code-quality workflow |
| Result | Only final report returns to parent |
When to Use
| Scenario | Use |
|---|---|
| After code modifications | /sniper-check src/ |
| Validate specific file | /sniper-check path/to/file.ts |
| Full project check | /sniper-check . |
| After refactoring | /sniper-check src/components/ |
Workflow
Execute the mandatory 6-phase code-quality workflow:
- PHASE 1+2 (PARALLEL): Launch both in parallel:
explore-codebase(Haiku) → Architecture discoveryresearch-expert(Sonnet) → Documentation verification
- PHASE 3: Grep all usages → Impact analysis
- PHASE 4: Run linters → Detect errors
- PHASE 5: Apply corrections → Minimal changes
- PHASE 6: Re-run linters → Zero errors
CRITICAL: Phases 1+2 must run in PARALLEL (two Task calls in one message).
Critical Rules
| Rule | Reason |
|---|---|
| Never skip phases 1+2 | Documentation-backed fixes only |
| Always run phases in order | Dependencies between phases |
| Zero linter errors | Non-negotiable exit criteria |
| Minimal changes only | Smallest fix necessary |
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 · 79 lines · 26 tokens per session scan A 6654068db9a6
sniper-check is a skill published in the GitHub repository fusengine/agents (33 stars, last pushed 8d ago), licensed MIT. It adds 26 tokens to every session and 625 once invoked, about $0.0001 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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