Cost Optimization

WebRun charges for session time and token usage. Three quick changes can cut your costs by 50% or more.

Quick Wins

1. Terminate Sessions Explicitly

Set terminateOnCompletion: true on your final task, or call terminate explicitly. This alone reduces costs by 50% if you’re currently letting sessions timeout.

// Single task - auto-terminates
const result = await fetch("https://connect.webrun.ai/start/run-task", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Authorization": `Bearer ${API_KEY}`
  },
  body: JSON.stringify({
    taskDetails: "Extract data from this page"
  })
});

// Multi-task - terminate on last task
const finalTask = await fetch("https://connect.webrun.ai/start/send-message", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Authorization": `Bearer ${API_KEY}`
  },
  body: JSON.stringify({
    sessionId,
    message: {
      actionType: "newTask",
      taskDetails: "Final task here",
      terminateOnCompletion: true
    }
  }
});

2. Write Concise Task Descriptions

Shorter descriptions = fewer input tokens. Be specific, not verbose. ❌ Verbose (150 tokens):

"Please navigate to the Amazon website and then perform a search for wireless keyboards. After you get the results, I need you to look through them carefully and find the ones that have good ratings, preferably above 4 stars, and then return me a list of the top 5 products with their titles, prices, and rating information."

✅ Concise (35 tokens):

"Go to Amazon, search 'wireless keyboard'. Return top 5 with rating ≥ 4.0 as JSON: title, price, rating."

Impact: 75% reduction in input tokens for this task.

3. Set `startingPoint` When Known

Skip navigation by providing the starting URL directly.

{
  "mode": "default",
  "initialTask": {
    "taskDetails": "Search for products",
    "startingPoint": "https://amazon.com"  // Skips "go to amazon.com" step
  }
}

Impact: Saves 5-10 seconds and ~500-1000 tokens per task.

Additional Optimizations

Set Appropriate `maxDuration`

Limit task duration to prevent runaway costs:

{
  "taskDetails": "Quick search task",
  "maxDuration": 30000  // 30 seconds max task duration
}

Guidelines:

Simple searches: 30,000ms (30s)
Form filling: 60,000ms (1 min)
Multi-step workflows: 120,000ms (2 min)

Reuse sessions for related tasks instead of creating new ones. ❌ Expensive:

await runTask("Go to amazon.com");      // New session
await runTask("Search for keyboards");  // Another new session
await runTask("Get first result");      // Yet another session

✅ Optimized:

const session = await startSession("Go to amazon.com");
await sendTask(session, "Search for keyboards");
await sendTask(session, "Get first result", { terminateOnCompletion: true });

Impact: 3x reduction in session overhead costs.

Limit Token Usage

For simple tasks, reduce token limits:

{
  "taskDetails": "Get product price",
  "maxInputTokens": 10000,   // Lower for simple tasks (default: 100000)
  "maxOutputTokens": 1000    // Lower for short responses (default: 100000)
}

Use `avoidDomains` to Prevent Detours

Block unnecessary domains to prevent wasted navigation:

{
  "taskDetails": "Research this topic",
  "avoidDomains": ["facebook.com", "twitter.com", "ads.example.com"]
}

Monitoring Costs

Real-time: Check usage.cost in every API response.

{
  "success": true,
  "sessionId": "abc123",
  "taskId": "xyz789",
  "type": "task_completed",
  "data": {
    "message": "Task completed successfully"
  },
  "usage": {
    "prompt_tokens": 12450,
    "completion_tokens": 3200,
    "total_tokens": 15650,
    "completion_time": 23.5,
    "cost": 0.0124
  }
}

Dashboard: View historical usage at app.webrun.ai/usage. During polling: The usage object updates in real-time as tasks execute.