What is agentmeter CLAUDE.md?

A project instruction file for AgentMeter, a command-line tool that tracks AI-agent token use and estimated costs in a local SQLite database. It also documents the terminal reports, web dashboard, exports, budget alerts, and development commands.

Use it when building, testing, type-checking, developing, or modifying AgentMeter and its Claude Code tool-use hook.

It gives coding agents the repository’s architecture, data flow, supported commands, and test expectations so they can change the project consistently.

How ymstar/agentmeter configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to ymstar/agentmeter. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/ymstar/agentmeter/master/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/ymstar/agentmeter

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/ymstar/agentmeter/claude-md/github.svg)](https://agentmods.dev/instructions/ymstar/agentmeter/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/ymstar/agentmeter/claude-md"><img src="https://agentmods.dev/badge/instructions/ymstar/agentmeter/claude-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/ymstar/agentmeter/claude-md"><img src="https://agentmods.dev/badge/instructions/ymstar/agentmeter/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 1,296 This file is loaded in full into every session.

When invoked 1,296 The same file — it is already loaded in full.

Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.01296	$0.01296
Opus 5.5	$0.00518	$0.00518
Sonnet 5.5	$0.00259	$0.00259
Haiku 4.5	$0.00130	$0.00130

Measured 2mo ago against content hash 89619d9f2f63, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade B, and why

agentmeter CLAUDE.md 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 2mo 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.

1. `init` command writes a `PostToolUse` hook into `~/.claude/settings.json` that runs `npx -y @ymstar/agentmeter hook`

CLAUDE.md · 106 lines

How it starts

The opening of the file, as written. The whole thing — 106 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

What is AgentMeter?

AgentMeter (@ymstar/agentmeter) is a CLI that tracks token consumption for AI agents (Claude Code, Cursor, Gemini CLI). It hooks into Claude Code's PostToolUse event to capture every tool call, records token usage and estimated costs into a local SQLite database, and provides terminal stats, a web dashboard, CSV/JSON export, and budget alerts.

Commands

npm run build          # Compile TypeScript to dist/ + copy dashboard static assets
npm run test           # Run all tests (vitest run)
npm run dev            # Watch mode compilation (tsc --watch)
npx tsc --noEmit       # Type-check only (used in CI lint job)

There is no linter or formatter configured. CI type-checks with npx tsc --noEmit on Node 20 and 22.

Architecture

ES modules ("type": "module" in package.json). Target ES2022 with Node16 module resolution.

Data Flow

init command writes a PostToolUse hook into ~/.claude/settings.json that runs npx -y @ymstar/agentmeter hook
Claude Code fires the hook after every tool use, passing tool name, input, response, session_id, model, agent_type, cwd via stdin JSON
hook command parses stdin, detects model/agent type via fallback chains, estimates tokens (three-layer: parse MCP usage fields → estimate from text at 4 chars/token ASCII, 2 chars/token CJK → character count), calculates cost, inserts into SQLite
SQLite lives at ~/.agentmeter/meter.db

Key Modules

src/index.ts — CLI entry point using node:util parseArgs. Routes to: init, hook, stats, dashboard, budget, export
src/commands/hook.ts — Core data collection. Contains detectModel() (input → env vars → settings file → default Sonnet) and detectAgentType() (input → env vars → UUID pattern → ~/.claude existence)
src/db/client.ts — MeterDB class wrapping better-sqlite3. Single tool_calls table with migration support (adds columns via ALTER TABLE based on PRAGMA table_info). WAL mode enabled
src/token/pricing.ts — Hardcoded MODEL_PRICING table for Claude, GPT, and Gemini models. Unknown models default to Claude Sonnet pricing
src/dashboard/server.ts — Raw node:http server (no framework). REST API at /api/overview, /api/daily, /api/tools, /api/sessions, /api/models, /api/agents, /api/calls. Default port 3940

Read the full file on GitHub · 106 lines

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.

2mo ago First seen · 106 lines · 1,296 tokens per session scan B 89619d9f2f63

Subscribe to this mod's changes

agentmeter CLAUDE.md is an instructions file published in the GitHub repository ymstar/agentmeter (1 stars, last pushed 5mo ago), licensed MIT. It adds 1,296 tokens to every session, about $0.0052 per session on Opus 5.5. 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 2026-08-31.

Analytics and metrics Claude Code ai-agent ai-cost anthropic cli-tool cost-monitoring

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 9,715 tokens

agentmeter: Instructions file for Claude Code