Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add melodic-software/claude-code-plugins/plugin install reviewWrote 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/melodic-software/claude-code-plugins/fanout)<a href="https://agentmods.dev/skills/melodic-software/claude-code-plugins/fanout"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/fanout/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/melodic-software/claude-code-plugins/fanout"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/fanout.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 | $0.00101 | $0.03659 |
| Opus 5.5 | $0.00040 | $0.01464 |
| Sonnet 5.5 | $0.00020 | $0.00732 |
| Haiku 4.5 | $0.00010 | $0.00366 |
Grade A, and why
fanout scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Pre-computed context
Current branch: !git branch --show-current 2>/dev/null || echo "unknown"
Working tree status (empty = clean): !{ git status --porcelain 2>/dev/null || echo "(git status unavailable)"; } | head -20
Open PRs (match headRefName to current branch above; baseRefName is the PR's real base): !gh pr list --json number,title,headRefName,baseRefName --limit 10 2>/dev/null || echo "unknown"
Committed diff size vs default-base merge base (recompute against the PR's baseRefName when it differs): !bash "${CLAUDE_PLUGIN_ROOT}/skills/fanout/scripts/diff-vs-base.sh" 2>/dev/null || echo "unavailable"
Uncommitted diff size: !git diff --shortstat HEAD 2>/dev/null || echo "unavailable"
Purpose
Breadth review. Where this plugin's quality-gate skill picks ONE lens per invocation, this skill fans out across MANY finding-producing surfaces at once, then normalizes their incomparable outputs into one severity-ranked report persisted to disk.
The hard problem this skill owns: the surfaces emit heterogeneous free-text on two independent axes (severity, confidence), and most populate only one. A 5-stage normalization pipeline (extraction → severity crosswalk → confidence enum → dedup → agreement/rank) is therefore unavoidable. context/findings-normalization.md.
Review modes report; a separate fix action applies. The default and run-everything modes fan out, normalize, and persist findings, mutating nothing but the findings file. The fix action consumes the persisted findings and is the only mode that touches the working tree.
Shared inputs
- Review diff base, when an open PR exists for the branch, its
baseRefNameis the base: dispatched surfaces diffgit merge-base origin/<baseRefName> HEAD. The pre-computed PR list above is capped; when the current branch is absent from it, rungh pr list --head <current-branch> --json number,baseRefNamebefore concluding no PR exists. Otherwisegit merge-base origin/HEAD HEAD(falling back to the remote's resolved default branch viagit ls-remote --symref, thenorigin/main, thenHEAD). Never a hardcodedgit diff HEAD, which is empty on a clean committed branch. - Severity vocabulary, the project's own review docs when present; else
${CLAUDE_PLUGIN_ROOT}/context/severity.md. - Findings location. Resolve through the plugin binding,
${CLAUDE_PLUGIN_ROOT}/reference/topic-docs.md, which owns the resolution ladder, the<branch-slug>and timestamp spec, the non-interactive collapse, and the self-ignore guard. Resolve the home; never assume its shape, the ladder's rungs do not all compose areviews/<branch-slug>segment, and the review modes' writer and thefixaction's reader must land in the same directory or findings go silently unseen. Read the binding rather than working from the default's shape.
What ships with it
8 files 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.
- 1mo ago First seen · 121 lines · 101 tokens per session scan A ac40bcdccb40
fanout is a skill published in the GitHub repository melodic-software/claude-code-plugins (26 stars, last pushed today), licensed MIT. It adds 101 tokens to every session and 3,659 once invoked, about $0.0004 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 2026-09-03.
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