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 agentmods add skills/appsvortex/arness/arn-code-feature-spec-teamsnpx skills add AppsVortex/arness --skill arn-code-feature-spec-teamsgit clone --depth 1 https://github.com/AppsVortex/arnessWhat 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 | $0.00123 | $0.04898 |
| Opus 5 | $0.00062 | $0.02449 |
| Sonnet 5 | $0.00025 | $0.00980 |
| Haiku 4.5 | $0.00012 | $0.00490 |
Grade B, and why
arn-code-feature-spec-teams scanned grade B with 1 finding 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 2d 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.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
- Add to `~/.claude/settings.json` under `"env"`: How it starts
The opening of the file, as written. The whole thing — 328 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Arness Feature Spec Teams
Develop a feature idea through structured debate between specialist teammates — architects and UX experts — before synthesizing a specification. Uses Claude Code's experimental Agent Teams feature for direct inter-agent communication. Each teammate proposes, critiques, and revises independently, producing a richer spec than a single-agent approach.
Pipeline position:
arn-code-feature-spec-teams (team: propose -> critique -> revise -> resolve) -> /arn-code-plan
This is an alternative to arn-code-feature-spec (single-agent). Use this when:
- The feature is complex enough to benefit from multiple perspectives
- There is a significant UI/UX component that needs specialist advocacy
- Multiple architectural approaches are viable and warrant debate
- You want trade-offs and disagreements surfaced explicitly
Prerequisites
If no ## Arness section exists in the project's CLAUDE.md, inform the user: "Arness is not configured for this project yet. Run /arn-planning to get started — it will set everything up automatically." Do not proceed without it. For standard single-agent feature spec, use arn-code-feature-spec instead.
Limitations compared to arn-code-feature-spec:
- XL feature decomposition is not supported. Use
arn-code-feature-specfor features that need to be broken into sub-features. - Draft file management is not supported. If the session crashes, re-run the skill from the beginning.
Workflow
Step 1: Check Agent Teams Availability
Run via Bash: echo $CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS
If the variable is NOT set to "1": Inform the user: "This skill requires Claude Code's experimental Agent Teams feature."
Provide setup instructions:
- Add to
~/.claude/settings.jsonunder"env":"CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS": "1" - Or set the environment variable before running Claude Code:
CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 claude
Suggest the alternative: "You can use /arn-code-feature-spec instead, which uses a single architect agent and doesn't require Agent Teams."
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 2d ago First seen · 328 lines · 123 tokens per session scan B 376af6efcaf4
arn-code-feature-spec-teams is a skill published in the GitHub repository AppsVortex/arness (33 stars, last pushed 1mo ago), licensed MIT. It adds 123 tokens to every session and 4,898 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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