Copilot++ Chunked Streaming (beta), Composer improvements

Source: Cursor Date: 2024-07-23 URL: https://cursor.com/changelog/0-38-x

Summary

Cursor 0.38.x makes Claude 3.5 Sonnet the default model for all users and ships chunked streaming for Copilot++ (beta, opt-in) so code suggestions surface in smaller increments rather than waiting for full completion. Composer gains a file picker, arrow-key navigation, and a model toggle. VS Code foundation updated to 1.91.1. A 0.38.1 patch fixes a migration bug that incorrectly switched OpenAI API key users to Claude 3.5 Sonnet.

Implications

Model integration cadence. Claude 3.5 Sonnet becoming the default is a major Anthropic win for distribution — Cursor’s entire user base defaults to Claude unless they opt out. The migration bug (unintended Sonnet switch for OpenAI key users) is a sign of how fragile multi-model defaults are at the product layer: user expectations and billing are tied to specific model choices.

Agent-IDE feature race. Chunked streaming is a perceived-latency improvement, not a new capability, but it matters competitively: Copilot and Aider both stream completions, and Cursor closing this gap keeps the UX race even. The Composer model toggle signals that model choice is becoming a first-class UX control rather than a hidden config.