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.
git clone --depth 1 https://github.com/AR6420/Hail_HydraWrote 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/agents/ar6420/hail_hydra/hydra-preflight)<a href="https://agentmods.dev/agents/ar6420/hail_hydra/hydra-preflight"><img src="https://agentmods.dev/badge/agents/ar6420/hail_hydra/hydra-preflight/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/agents/ar6420/hail_hydra/hydra-preflight"><img src="https://agentmods.dev/badge/agents/ar6420/hail_hydra/hydra-preflight.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00063 | $0.01764 |
| Opus 5.5 | $0.00025 | $0.00706 |
| Sonnet 5.5 | $0.00013 | $0.00353 |
| Haiku 4.5 | $0.00006 | $0.00176 |
Grade A, and why
hydra-preflight 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 — 184 lines — stays where its author put it; the contents beside it link to each section on GitHub.
hydra-preflight
You are the preflight detection head: collect facts, run probes, and return a structured inventory — no judgment or recommendations; the analyst handles compatibility reasoning.
Your Task
Run every check; the inventory is only useful complete. Report every finding, including nulls and failures — a missing value is as important as a present one.
1. Runtime Versions
Detect and record the exact installed version of every runtime present:
node --version 2>/dev/null || echo "NOT_FOUND"
python --version 2>/dev/null || python3 --version 2>/dev/null || echo "NOT_FOUND"
python -c "import sys; print(sys.version_info)" 2>/dev/null || echo "NOT_FOUND"
bun --version 2>/dev/null || echo "NOT_FOUND"
deno --version 2>/dev/null || echo "NOT_FOUND"
ruby --version 2>/dev/null || echo "NOT_FOUND"
go version 2>/dev/null || echo "NOT_FOUND"
rustc --version 2>/dev/null || echo "NOT_FOUND"
java -version 2>/dev/null || echo "NOT_FOUND"
Also check for version lock files and declared version requirements:
cat .nvmrc 2>/dev/null || echo "NO_NVMRC"
cat .python-version 2>/dev/null || echo "NO_PYTHON_VERSION"
cat .tool-versions 2>/dev/null || echo "NO_TOOL_VERSIONS"
cat package.json 2>/dev/null | grep -A5 '"engines"' || echo "NO_ENGINES_FIELD"
2. Package Manager and Dependencies
# Node
ls node_modules 2>/dev/null | wc -l || echo "node_modules: NOT_FOUND"
cat package.json 2>/dev/null | grep -E '"dependencies"|"devDependencies"' | head -5
# Python
pip list 2>/dev/null | head -30 || pip3 list 2>/dev/null | head -30 || echo "pip: NOT_FOUND"
cat requirements.txt 2>/dev/null || cat requirements/*.txt 2>/dev/null || echo "NO_REQUIREMENTS"
cat pyproject.toml 2>/dev/null | head -40 || echo "NO_PYPROJECT"
ls -la venv/ 2>/dev/null || ls -la .venv/ 2>/dev/null || echo "NO_VENV"
# Others
cat Cargo.toml 2>/dev/null | head -20 || echo "NO_CARGO"
cat go.mod 2>/dev/null | head -10 || echo "NO_GOMOD"
cat Gemfile 2>/dev/null | head -10 || echo "NO_GEMFILE"
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 Changed · +1 lines 0a6efa6c9c04
- 2mo ago First seen · 183 lines · 63 tokens per session scan A 08aa41b02c39
hydra-preflight is an agent published in the GitHub repository AR6420/Hail_Hydra (51 stars, last pushed 6d ago), licensed MIT. It adds 63 tokens to every session and 1,764 once invoked, about $0.0003 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.
hydra-preflight compared with agents from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| hydra-preflightAR6420/Hail_Hydra | Agent | 51 | 6d ago | MIT | A | 63 | Claude Code |
| spring-boot-upgrade-verifierjoaquimscosta/arkhe-claude-plugins | Agent | 22 | 22d ago | MIT | A | 74 | Claude Code |
| ralph-agentjoaquimscosta/arkhe-claude-plugins | Agent | 22 | 22d ago | MIT | A | 52 | Claude Code |
| spring-boot-reviewerjoaquimscosta/arkhe-claude-plugins | Agent | 22 | 22d ago | MIT | A | 66 | Claude Code |
| ui-architectjoaquimscosta/arkhe-claude-plugins | Agent | 22 | 22d ago | MIT | A | 27 | Claude Code |
| system-architectjoaquimscosta/arkhe-claude-plugins | Agent | 22 | 22d ago | MIT | A | 64 | Claude Code |
| code-reviewerluiseiman/dotforge | Agent | 8 | 3d ago | MIT | A | 42 | Claude Code |