Windsurf

Windsurf is built by Codeium and centres on Cascade, an agentic AI that operates differently from standard code completions. Instead of waiting for you to type and then suggesting what comes next, Cascade reads your entire codebase, understands the goal you've described, and then executes a plan — creating files, modifying multiple functions across different modules, running the code, reading the error output, and iterating until the task is done. For multi-file refactoring tasks or adding a feature that touches several layers of the stack, the difference from Copilot or Tabnine is dramatic. You describe what you want, and Cascade figures out the implementation order.

The free plan is generous by the standards of this category — you get Cascade flows, the full IDE and autocomplete without paying anything, though the number of Cascade 'actions' (each LLM call Cascade makes during a task) is capped. In practice, a single complex Cascade run can consume 20-40 actions, which burns through the free allocation in a session or two. Pro at $15/mo gives you significantly more. Compared directly to Cursor, which is the main competitor at a similar price point, Windsurf's Cascade tends to be less conservative — it takes more initiative, which cuts both ways. It can accomplish more with less prompting, but it also occasionally makes changes you didn't ask for. The autocomplete engine from Codeium is fast and accurate for line completions, which makes Windsurf viable as an everyday editor even when you're not running Cascade tasks.