Traditional QA automation relies on brittle selectors and rigid APIs. When a UI changes, scripts break. The Coasty computer use API lets you build a QA testing bot that watches the screen, interprets elements, and acts like a human. It provides real-time feedback, handles dynamic layouts, and validates both user flows and UI states.
How it works
The computer use API drives a real desktop or browser. You send a task description or an endpoint to start a run. The server provisions a machine, launches the agent, and executes actions (click, type, scroll) based on the current state. Each agent step is billed $0.05. The system streams events through Server-Sent Events so you can watch progress in real time.
Create a self-running QA run for a login test. This example starts a run with a task description and a deadline. Replace COASTY_API_KEY with your key from the environment.
export COASTY_API_KEY=your_api_key_here
curl -X POST https://coasty.ai/v1/runs \
-H "Authorization: Bearer $COASTY_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"machine_id": "your_machine_id",
"task": "Open the login page, type username and password, and verify the dashboard appears.",
"cua_version": "v4",
"deadline_seconds": 120,
"on_awaiting_human": "pause"
}'Run states and events
- Runs can be queued, running, awaiting_human, succeeded, failed, cancelled, or timed_out.
- GET /v1/runs returns a list of runs with status and IDs.
- GET /v1/runs/{id} fetches details for a specific run.
- POST /v1/runs/{id}/cancel aborts a run.
- POST /v1/runs/{id}/resume continues a paused run.
- GET /v1/runs/{id}/events streams events using Server-Sent Events with Last-Event-ID for reconnection.
Each agent step costs $0.05 in credits.
Where this beats brittle automation
A computer use agent does not depend on static selectors or fixed API endpoints. It sees the screen, reads text, and acts on what is visible. If a button moves or changes label, the agent can still find it by description. This makes QA testing more resilient to UI changes and better at simulating real user behavior.
You can expand this bot into a full QA pipeline. Create workflows with task, assert, if, and loop steps to cover complex scenarios. Add retries and human approval for edge cases. Get your API key at https://coasty.ai/developers and start building a self-running QA testing bot with the computer use API.
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