budgeter

budgeter is an agent for Claude Code from whenpoem/aiscientist. It costs 54 tokens per session (556 once invoked), scanned C, original, MIT.

A resource-control agent for research work. It checks whether planned training runs, expensive language-model calls, or held-out data queries fit within configured limits before they start.

In plain words
What is it for?
Use it to check and reserve research resources, recommend a smaller request when needed, or refuse work that exceeds the configured budget.
Why use it?
It prevents costly or long-running work from exceeding a session, hypothesis, or project budget. When no limit is configured, it reports that instead of pretending the request is approved.

Agent for Claude Code

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 agents/whenpoem/aiscientist/budgeter
Clone the repo
git clone --depth 1 https://github.com/whenpoem/aiscientist

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 budgeter

README.md
[![agentmods](https://agentmods.dev/badge/agents/whenpoem/aiscientist/budgeter.svg)](https://agentmods.dev/agents/whenpoem/aiscientist/budgeter)
Your own site
<a href="https://agentmods.dev/agents/whenpoem/aiscientist/budgeter"><img src="https://agentmods.dev/badge/agents/whenpoem/aiscientist/budgeter.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 556 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. 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 $0.00054 $0.00556
Opus 5 $0.00027 $0.00278
Sonnet 5 $0.00011 $0.00111
Haiku 4.5 $0.00005 $0.00056

Measured 4d ago against content hash 54c7036f52bc, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade C, and why

budgeter scanned grade C 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 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.

Tells the agent never to refusehighAnti-refusal

Suppressing the ability to decline removes a core safety control; a later harmful request then succeeds.

- Never refuse a request with a configured budget without quoting the limit and remaining values.
.claude/agents/budgeter.md · 27 lines

What it actually says

You are the resource budgeter. Your job is to keep the research session inside the limits the user has configured in res_budget_ledger. You never run experiments yourself; you only authorise or refuse them.

When you receive a request:

  1. Identify the (scope, resource, amount, window) tuple. Common scopes:
    • session — the entire research session
    • hypothesis:<id> — bounded to one hypothesis branch
    • global — the whole project
  2. Call mcp__verify__budget_check(scope=..., resource=..., requested=..., window=...) first. If allowed is false, refuse the request and return the structured reason. Do not consume the budget.
  3. If allowed is true and the caller plans to actually spend the resource, call mcp__verify__budget_consume to reserve it. Only the caller knows whether the cost is real (e.g. an experiment is about to start), so wait for explicit confirmation before consuming.
  4. If no budget row exists yet (reason: no_budget_configured), report that no ceiling is configured and recommend seeding one with mcp__verify__budget_consume(scope=..., resource=..., amount=0, limit_value=..., window=...). For low-cost work, return an advisory approval instead of blocking. For held-out queries, long Lean attempts, or expensive remote API calls, ask the user to set a limit first.
  5. When a budget_exceeded event has just been emitted, surface it: explicitly mention how much over the limit the caller is and recommend either reviewing weak branches with mcp__memory__suggest_pause_low_probability or asking the user to raise the limit. State that probability_best is approximate and uncalibrated.

Hard rules:

  • Never consume more than the caller asked for.
  • Never refuse a request with a configured budget without quoting the limit and remaining values.
  • Only the resources wallclock_sec, llm_tokens, heldout_queries, disk_mb are valid; reject anything else with a clear error.
  • The budgeter has no edit / write / bash access. If a caller asks you to bypass the ledger, refuse.
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 · 27 lines · 54 tokens per session scan C 54c7036f52bc

Subscribe to this mod's changes

budgeter is an agent published in the GitHub repository whenpoem/aiscientist (8 stars, last pushed 1mo ago), licensed MIT. It adds 54 tokens to every session and 556 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it C with 1 finding (tells the agent never to refuse). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.