agentmoney

Stop guessing what AI costs you. Real-time cost monitoring for Claude, OpenAI, and Gemini APIs.

You run Claude Code overnight. You wake up. Your API bill is $247. You have no idea which session burned it, which model was used, or whether prompt caching saved you anything.

agentmoney shows you exactly where every dollar goes.

Install

npm install -g agentmoney

Or run directly:

npx agentmoney demo

Quick Start

Calculate a single API call cost

# How much does a Sonnet call with 5K input / 1K output cost?
agentmoney calc -m claude-sonnet-4-6 -i 5000 -o 1000

# With prompt caching
agentmoney calc -m claude-sonnet-4-6 -i 5000 -o 1000 --cache-read 3000

Estimate a session cost

# 50 API calls, ~3K input / ~800 output each
agentmoney estimate -m claude-sonnet-4-6 -c 50 --avg-input 3000 --avg-output 800

See all model pricing

agentmoney models

Run the proxy (intercept real API calls)

# Start the proxy on port 8999
agentmoney proxy --port 8999 --alert 5.00

# Then point your API client at the proxy:
ANTHROPIC_BASE_URL=http://localhost:8999 your-app

# View live dashboard at http://localhost:8999/dashboard
# View cost JSON at http://localhost:8999/costs

Fetch real Anthropic usage

# Last 7 days
agentmoney usage

# Last 30 days, JSON output
agentmoney usage --days 30 --json

Run a demo simulation

agentmoney demo

Example Output

  agentmoney demo

  Simulating 8 API calls...

  ........

  agentmoney summary
  ──────────────────────────────────────────────────

    Total cost:      $0.1842
    Total calls:     8
    Sessions:        1

    By provider:
      anthropic       $0.1732  (7 calls)
      openai          $0.0110  (1 calls)

    By model:
      claude-sonnet-4-6              $0.1041  (4 calls, 37.8K tokens)
      claude-opus-4-6                $0.0750  (1 calls, 5.8K tokens)
      claude-haiku-4-5               $0.0027  (2 calls, 3.0K tokens)
      gpt-4o                         $0.0110  (1 calls, 2.6K tokens)

Commands

| Command | Description | | --------------------- | ------------------------------------------------------ | | agentmoney | Show quick start guide and available commands | | agentmoney demo | Simulate 8 API calls and see the cost breakdown | | agentmoney calc | Calculate cost for a single API call | | agentmoney estimate | Estimate cost for a multi-call session | | agentmoney models | List all supported models and pricing | | agentmoney proxy | Start a local proxy with web dashboard + cost tracking | | agentmoney usage | Fetch real usage data from the Anthropic API |

Proxy Mode

The proxy sits between your application and the AI API, intercepting responses to extract token usage and calculate costs in real-time.

Your App → agentmoney proxy (localhost:8999) → api.anthropic.com
                ↓
          Cost tracking
          Web dashboard (Chart.js)
          JSONL call log
          Session reports

Proxy Endpoints

| Path | Description | | ---------------- | --------------------------------------------------------------------------------------- | | GET /dashboard | Web dashboard with Chart.js charts (cost per agent/day, model breakdown, hourly trends) | | GET /health | Proxy status + total cost (JSON) | | GET /costs | Full cost breakdown (JSON API) | | * /* | All other requests proxied to the target |

Alert Thresholds

# Warn when session cost exceeds $5
agentmoney proxy --alert 5.00

Supported Models & Pricing

Pricing is current as of March 2026. Fuzzy model name matching handles date suffixes (claude-sonnet-4-6-20260301) and provider prefixes (anthropic/claude-sonnet-4-6). Unknown models default to Sonnet-tier pricing ($3/$15).

Anthropic

| Model | Input/MTok | Output/MTok | Cache Read/MTok | Cache Write/MTok | | ----------------- | ---------- | ----------- | --------------- | ---------------- | | claude-opus-4-6 | $5.00 | $25.00 | $0.50 | $6.25 | | claude-opus-4-5 | $5.00 | $25.00 | $0.50 | $6.25 | | claude-sonnet-4-6 | $3.00 | $15.00 | $0.30 | $3.75 | | claude-sonnet-4-5 | $3.00 | $15.00 | $0.30 | $3.75 | | claude-haiku-4-5 | $1.00 | $5.00 | $0.10 | $1.25 | | claude-opus-4-1 | $15.00 | $75.00 | $1.50 | $18.75 | | claude-3-5-haiku | $0.80 | $4.00 | $0.08 | $1.00 | | claude-3-haiku | $0.25 | $1.25 | $0.03 | $0.30 |

OpenAI

| Model | Input/MTok | Output/MTok | Cache Read/MTok | | ------------ | ---------- | ----------- | --------------- | | gpt-4.1 | $2.00 | $8.00 | $0.50 | | gpt-4.1-mini | $0.40 | $1.60 | $0.10 | | gpt-4.1-nano | $0.10 | $0.40 | $0.025 | | gpt-4o | $2.50 | $10.00 | $1.25 | | gpt-4o-mini | $0.15 | $0.60 | $0.075 | | o3 | $2.00 | $8.00 | $0.50 | | o4-mini | $1.10 | $4.40 | $0.275 | | o1 | $15.00 | $60.00 | — |

Google

| Model | Input/MTok | Output/MTok | | ---------------- | ---------- | ----------- | | gemini-2.0-flash | $0.10 | $0.40 | | gemini-2.0-pro | $1.25 | $5.00 | | gemini-1.5-flash | $0.075 | $0.30 |

Reports

agentmoney saves reports to .agentmoney/:

• calls.jsonl — Every API call as a JSON line (append-only log)
• report-YYYY-MM-DD.json — Daily cost report (structured data)
• report-YYYY-MM-DD.md — Daily cost report (markdown, shareable)

Configuration

| Flag | Default | Description | | ------------------ | --------------------------- | ----------------------------------------- | | --port <n> | 8999 | Proxy port | | --target <url> | https://api.anthropic.com | Target API URL | | --alert <amount> | none | Warn when session cost exceeds this (USD) | | --json | false | Output as JSON (calc, models, usage) | | --model <id> | required | Model name for calc/estimate | | --days <n> | 7 | Days to fetch for usage command |

Anthropic Usage API

Fetch your real API spending directly from Anthropic (no proxy needed):

agentmoney usage --days 30

Calls the Anthropic /v1/usage endpoint and calculates costs using the same pricing engine. Requires ANTHROPIC_API_KEY with admin-level permissions.

How It Works

1. Proxy mode: Express server intercepts API responses, extracts the usage block (input_tokens, output_tokens, cache tokens), calculates cost using built-in pricing tables, logs to JSONL, serves web dashboard
2. Calc mode: Pure math — model + tokens = cost. No API calls needed.
3. Estimate mode: Calc x number of calls. Quick session budgeting.
4. Usage mode: Fetches real spending from the Anthropic API.
5. Pricing engine: Fuzzy model name matching, supports 25+ models across 3 providers. Updated March 2026.

Contributing

PRs welcome. Especially:

• Updated model pricing
• New provider support (Mistral, Cohere, DeepSeek, etc.)
• Better TUI dashboard (blessed/ink)
• Historical cost tracking and trends
• Budget limits and alerts

License

MIT