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 frankxai/claude-skills-library --skill neutron-loggit clone --depth 1 https://github.com/frankxai/claude-skills-libraryWrote 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/frankxai/claude-skills-library/neutron-log)<a href="https://agentmods.dev/skills/frankxai/claude-skills-library/neutron-log"><img src="https://agentmods.dev/badge/skills/frankxai/claude-skills-library/neutron-log/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/frankxai/claude-skills-library/neutron-log"><img src="https://agentmods.dev/badge/skills/frankxai/claude-skills-library/neutron-log.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 | $0.00065 | $0.01002 |
| Opus 5.5 | $0.00026 | $0.00401 |
| Sonnet 5.5 | $0.00013 | $0.00200 |
| Haiku 4.5 | $0.00006 | $0.00100 |
Grade A, and why
neutron-log 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 yesterday.
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.
Neutron log
A savings figure from a README is a claim. A figure from your own session is a result. This skill produces results.
What counts as a result
A result needs all four:
- Same task, same repo, same starting commit for the baseline and the candidate.
- Quality held. The tests, checks or acceptance criteria that passed in the baseline pass in the candidate. A cheaper wrong answer is a loss.
- A named unit. Bytes, estimated tokens, or billed tokens. Say which. RTK estimates tokens as bytes divided by four, so its percentages are reliable and its absolute token counts are not.
- A date and a machine. Tool versions drift. Record them.
Anything else is written down as unmeasured.
Fast check: command output
For shell-output compressors, compare raw and compressed output on real commands in a real repo:
node <pack>/scripts/neutron.mjs bench # table
node <pack>/scripts/neutron.mjs bench --md # markdown, for docs
node <pack>/scripts/neutron.mjs bench --json # with RTK version, platform and repo commit
<pack> is the plugin root, or .claude/neutron after install.mjs. Run it from the repo you care about. Its git diff HEAD~5 needs at least six commits.
The bench only compares commands whose filtered output is meant to carry the same information. A row is skipped, not counted as a saving, when the filter fails or exits differently from the raw command.
This measures bytes only. It proves the filter shrinks the output. It does not prove the agent still has what it needs, so spot-check one compressed output by hand for each command class before trusting it.
Full check: a session
- Pick two or three tasks you actually do. A bug fix with a failing test, a repo-wide search and summary, a review of a medium diff.
- Run each task twice from the same commit: once with the candidate off, once on. Use a fresh session each time.
- Record, for each run: tokens in, tokens out, cache read and cache write if shown, tool-call count, wall time, and whether the acceptance check passed.
- Read the sources:
ccusage sessionfor per-session tokens and cost.rtk gainfor what RTK filtered, andrtk gain --historyif you need per-command detail.headroom perffor proxy-side savings, with the proxy running.
- Compare. Report the delta per metric and the quality verdict side by side.
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.
- yesterday First seen · 79 lines · 65 tokens per session scan A 972860a629cb
neutron-log is a skill published in the GitHub repository frankxai/claude-skills-library (47 stars, last pushed yesterday), licensed MIT. It adds 65 tokens to every session and 1,002 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 2026-10-15.
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