Cost Tracking

AgentLens tracks token usage and estimated costs across all your agents, giving you visibility into LLM spending.

How It Works

Agents log cost_tracked events with token counts and estimated cost:

Tool: agentlens_log_event
Arguments: {
  "sessionId": "01HXYZ...",
  "agentId": "my-agent",
  "eventType": "cost_tracked",
  "payload": {
    "provider": "anthropic",
    "model": "claude-sonnet-4-20250514",
    "inputTokens": 1500,
    "outputTokens": 800,
    "totalTokens": 2300,
    "costUsd": 0.0092,
    "trigger": "search_database"
  }
}

Cost Payload Schema

Field	Type	Required	Description
provider	string	✅	LLM provider (e.g., anthropic, openai)
model	string	✅	Model name
inputTokens	number	✅	Input/prompt tokens
outputTokens	number	✅	Output/completion tokens
totalTokens	number	✅	Total tokens
costUsd	number	✅	Estimated cost in USD
trigger	string	—	What triggered this cost (e.g., tool name)

Dashboard Views

Session Cost

Each session shows its total estimated cost in the sessions list and detail view.

Cost Analytics

The Analytics → Costs view shows:

• Cost by agent — Which agents are most expensive?
• Cost over time — Spending trends by hour/day/week
• Token breakdown — Input vs output tokens by agent

Cost Alerts

Set up alerts to catch cost spikes:

curl -X POST http://localhost:3400/api/alerts/rules \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer als_your_key" \
  -d '{
    "name": "Daily cost spike",
    "condition": "cost_exceeds",
    "threshold": 50.0,
    "windowMinutes": 1440,
    "enabled": true
  }'

API Endpoints

Query cost data programmatically:

# Cost breakdown by agent and time
curl "http://localhost:3400/api/analytics/costs?from=2026-02-01&to=2026-02-08&granularity=day" \
  -H "Authorization: Bearer als_your_key"

See Analytics API Reference for full details.