You're out of premium credits
Windsurf meters premium-model usage in prompt credits; agentic Cascade sessions burn them fastest. When credits run out you're on base models until the cycle resets, you buy add-ons, or you move agent work to an unmetered provider.
Credit systems punish exactly the workflows agents are for — iterate-until-done loops. If your usage pattern is “let it run”, metered credits will always be the bottleneck.
Windsurf doesn't take a custom base URL for its premium models — but Cline and Roo Code in VS Code do the same agentic work pointed at Standard Compute: flat monthly price, no credits to count. Guides: /integrations/cline, /integrations/roo-code.
On standard monthly plans, no — they reset each billing cycle. Add-on packs follow their own terms.