brain-score

brain-score is a command for coding agents from itsribbZ/Godspeed. It costs 27 tokens per session (370 once invoked), scanned A, original, MIT.

A command that rates a written prompt on a severity scale from S0 to S5 and prints a suggested model, effort level, score, and signal breakdown.

In plain words
What is it for?
Use it to inspect prompts based on their length, code, file references, and reasoning demands, while receiving the tool's raw classification output.
Why use it?
It helps decide how much model capacity and reasoning effort a prompt may need before running it.

Command

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the godspeed plugin — 18 skills, 3 commands, 1 agent, 5 hooks shipped together

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.

agentmods
npx agentmods add commands/itsribbz/godspeed/brain-score
Clone the repo
git clone --depth 1 https://github.com/itsribbZ/Godspeed

Or install godspeed, the plugin that ships this one along with the rest of its 18 skills, 3 commands, 1 agent, 5 hooks.

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 brain-score

README.md
[![agentmods](https://agentmods.dev/badge/commands/itsribbz/godspeed/brain-score.svg)](https://agentmods.dev/commands/itsribbz/godspeed/brain-score)
Your own site
<a href="https://agentmods.dev/commands/itsribbz/godspeed/brain-score"><img src="https://agentmods.dev/badge/commands/itsribbz/godspeed/brain-score.svg" alt="Measured on agentmods" height="20"></a>
Per session 27 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 370 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00027 $0.00370
Opus 5 $0.00014 $0.00185
Sonnet 5 $0.00005 $0.00074
Haiku 4.5 $0.00003 $0.00037

Measured 4d ago against content hash da62af35f30f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

brain-score 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 4d 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.

plugins/godspeed/commands/brain-score.md · 48 lines

What it actually says

/brain-score — Toke Brain Prompt Classifier

Classify the prompt in $ARGUMENTS against the live routing manifest.

Arguments received: $ARGUMENTS

Execution

Run this exact command via the Bash tool and echo the full output verbatim — no preamble, no rewrite, no summary. Users want the raw classifier signal.

python ${CLAUDE_PLUGIN_ROOT}/automations/brain/brain_cli.py score "$ARGUMENTS"

Output contract

brain score prints in this shape (do not reformat):

Tier:    S<N>
Model:   <haiku|sonnet|opus>    Effort: <low|medium|high>
Score:   0.<NNN>
Reason:  score=... | top:<signals> | <escalation-notes>

Signals:
  prompt_length   0.NNN  #####
  code_blocks     0.NNN
  file_refs       0.NNN
  reasoning       0.NNN
  ...

Guardrails fired: <list, if any>

Rules

  • NEVER ask for confirmation — execute immediately.
  • If $ARGUMENTS is empty, print: usage: /brain-score <prompt text> and stop.
  • If the Python command errors, show stderr verbatim — never swallow the error.
  • This command is read-only. No file writes, no settings edits.
  • Do not add interpretation beyond the raw classifier output unless the user explicitly asks for analysis after.
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. 4d ago First seen · 48 lines · 27 tokens per session scan A da62af35f30f

Subscribe to this mod's changes

brain-score is a command published in the GitHub repository itsribbZ/Godspeed (1 stars, last pushed 2mo ago), licensed MIT. It adds 27 tokens to every session and 370 once invoked, about $0.0001 per session on Opus 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 2026-08-31.