Selenium vs TinyFish

Selenium

Selenium is stable, Apache-2.0 software on 4.51.0 with bindings in five languages, CI passing on trunk, an llms.txt and an agent guide added in September 2026. It has no MCP server of its own, Selenium Manager sends usage statistics by default, and Grid accepts unauthenticated sessions unless a username and password are set.

TinyFish

OpenAPI documents are published for five APIs, errors carry typed codes and request IDs, and Search and Fetch are free within daily allowances. The terms let Tiny Fish train its models on customer data, run creation takes no idempotency keys, and the status page shows an hour or more of downtime on several days for the Browser and Search APIs.

Selenium

1. Install with pip install selenium (Python 3.10 or later) and let Selenium Manager fetch drivers. Do not set driver paths
2. Use WebDriverWait with expected conditions, never fixed sleeps, and do not mix implicit and explicit waits
3. Set SE_AVOID_STATS=true to stop Selenium Manager sending usage statistics
4. Point coding agents at https://www.selenium.dev/llms.txt. Most Selenium 2 and 3 era examples use removed APIs
5. Set --username and --password before exposing a Grid beyond localhost. Check http://localhost:4444/status before creating sessions

TinyFish

1. Check result as well as status. A run can be COMPLETED while the goal failed, with result.status set to failure
2. Don't retry POST /v1/automation/run blindly after a timeout. There are no idempotency keys, so list runs first to avoid duplicates
3. Use /v1/automation/run-async or /run-sse when a run may need cancelling. Runs started with the synchronous endpoint can't be cancelled
4. Allow 60 seconds for Browser session creation, connect Playwright to cdp_url (not base_url), and DELETE the session when done because billing is per minute
5. Never put passwords in goal, which is logged. Pass use_vault: true with credential_item_ids, or use_profile: true for saved login state