hydra

hydra is a skill for Claude Code from AR6420/Hail_Hydra. It costs 83 tokens per session (6,887 once invoked), scanned A, original, MIT.

A multi-agent workflow for Claude Code that divides coding work among specialised helper agents and checks changes with safety scans. It defines when to run those checks and how to respond to their findings.

In plain words
What is it for?
Use it during coding tasks that involve delegation, file exploration, testing, documentation or checking changes for security and quality issues.
Why use it?
It provides a shared process for delegating routine work while keeping review and security checks in the loop.

Skill for Claude Code

Written for Claude Code: PostToolUse hook event. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions subagents.

Good fit Use it during coding tasks that involve delegation, file exploration, testing, documentation or checking changes for security and quality issues.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/ar6420/hail_hydra/content
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.

Any agent
npx skills add AR6420/Hail_Hydra --skill content
Clone the repo
git clone --depth 1 https://github.com/AR6420/Hail_Hydra

Made for: Claude Code.

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 hydra

README.md
[![agentmods](https://agentmods.dev/badge/skills/ar6420/hail_hydra/content/github.svg)](https://agentmods.dev/skills/ar6420/hail_hydra/content)
Your own site
<a href="https://agentmods.dev/skills/ar6420/hail_hydra/content"><img src="https://agentmods.dev/badge/skills/ar6420/hail_hydra/content/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.

agentmods 80×15 button for hydra

Your own site · 80×15
<a href="https://agentmods.dev/skills/ar6420/hail_hydra/content"><img src="https://agentmods.dev/badge/skills/ar6420/hail_hydra/content.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 83 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 6,887 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 7 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high YARA Match · line 432
    YARA rule matched a hack tool or exploit indicator (offensive tools, reconnaissance, privilege escalation, or exploit frameworks).
    Fix: Remove offensive tool references and exploit code. Legitimate agent skills should not contain penetration testing tools, exploit frameworks, or reconnaissance utilities.
  • medium Excessive Agency · line 47
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • medium Agent Snooping · line 98
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
  • medium Excessive Agency · line 380
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • medium MCP Rug Pull · line 526
    npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.
    Fix: Pin the version: npx @scope/[email protected]
  • medium MCP Rug Pull · line 570
    npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.
    Fix: Pin the version: npx @scope/[email protected]
  • medium MCP Rug Pull · line 571
    npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.
    Fix: Pin the version: npx @scope/[email protected]
How audits are shown
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 5.1 $0.00083 $0.06887
Opus 5.5 $0.00033 $0.02755
Sonnet 5.5 $0.00017 $0.01377
Haiku 4.5 $0.00008 $0.00689

Measured 1mo ago against content hash 1c3fafb6e012, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

hydra 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.

content/SKILL.md · 603 lines

How it starts

The opening of the file, as written. The whole thing — 603 lines — stays where its author put it; the contents beside it link to each section on GitHub.

🐉 Hydra — Multi-Headed Speculative Execution

You are the orchestrator of a multi-agent toolkit: route substantial work to cheaper specialized heads, and keep your own reasoning for planning, verification, and genuinely hard problems.

Core Protocols

The sentinel scan is the safety guarantee that replaces the orchestrator re-reading every diff — run it after every code change.

Protocol 1: Sentinel Scan After Code Changes

When any agent returns output containing ⚠️ HYDRA_SENTINEL_REQUIRED, dispatch hydra-sentinel-scan with the files and changes listed in the trigger block — before presenting results to the user, before running any other agents.

This is blocking: the user does not see the code changes until sentinel completes.

Sequence:

  1. Receive agent output containing ⚠️ HYDRA_SENTINEL_REQUIRED
  2. Immediately dispatch hydra-sentinel-scan AND hydra-guard in parallel
  3. Wait for both to complete
  4. If sentinel-scan finds issues → dispatch hydra-sentinel (deep analysis)
  5. Wait for deep analysis
  6. Then present results to the user

If the agent output contains ✅ HYDRA_NO_CODE_CHANGES, skip sentinel. Present results immediately.

Protocol 2: Sentinel Fix Decision Tree

When hydra-sentinel confirms real issues:

TRIVIAL (auto-fix without asking): Import renames, file path updates, barrel file re-exports. → Dispatch hydra-coder to fix. Re-run sentinel-scan to verify. → Tell user: "Sentinel caught [issue]. Auto-fixed."

MEDIUM (present to user, offer to fix): API contract mismatches, missing env vars, signature mismatches. → Show the sentinel report. Ask: "Want me to fix these?"

COMPLEX (report only): Architectural changes, migration needed, business logic decisions. → Show the report. Let user decide.

Response Compression — Orchestrator

Apply light compression to your responses: keep full grammar and natural prose, remove the waste. Done right, a careful reader notices responses are tighter and nothing sounds robotic.

Read the full file on GitHub · 603 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. 1mo ago First seen · 603 lines · 83 tokens per session scan A 1c3fafb6e012

Subscribe to this mod's changes

hydra is a skill published in the GitHub repository AR6420/Hail_Hydra (49 stars, last pushed 12d ago), licensed MIT. It adds 83 tokens to every session and 6,887 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.

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