OpenAI’s GPT-4.1 has some pretty standout results on SWE-bench Verified, Aider’s polyglot diff, and this leads to immediate adoption by top AI coding IDEs like Windsurf and Cursor.

SWE-bench: Real-World Coding, Real Progress

  • GPT-4.1 scores 54.6% on SWE-bench Verified, up from 33.2% for GPT-4o and 38% for GPT-4.5—a 21.4% absolute gain over 4.0 (OpenAI).
  • SWE-bench tests the model’s ability to solve real software engineering tasks in open-source Python repos, including bug fixes and feature additions.
  • This jump means GPT-4.1 is much better at exploring codebases, generating code that runs, and passing tests—crucial for devs building agents or automation.

Aider Polyglot: Multi-Language, Diff-Based Coding

  • Aider’s polyglot diff benchmark measures how well models handle code changes across multiple languages and output only the necessary diffs.
  • GPT-4.1 more than doubles GPT-4o’s score and beats GPT-4.5 by 8% absolute (OpenAI).
  • The model is specifically trained to follow diff formats more reliably, saving time and reducing merge conflicts for devs who rely on precise, minimal code changes.
  • For those who prefer full file rewrites, GPT-4.1’s output token limit is now 32,768—double that of GPT-4o.

Windsurf: Real-World IDE Impact

  • Windsurf now supports GPT-4.1, free for all users from April 14–21 (Windsurf Changelog, Reddit).
  • Performance gains:
    • 60% higher coding accuracy vs. GPT-4o
    • 30% more efficient tool calling
    • 50% fewer repeated/unnecessary edits
    • 40% fewer unnecessary file reads
    • 70% fewer incorrect file modifications
    • 50% less verbosity (details).
  • These improvements mean faster iteration, smoother workflows, and more accepted code changes on first review for engineering teams.

Cursor: GPT-4.1 Now Live

  • Cursor IDE has added GPT-4.1 as a selectable model—just enable it in Settings → Models (Cursor Forum, Reddit).
  • It’s currently free to try, letting users experience the new coding and tool-calling capabilities firsthand.
  • Cursor’s integration means developers can leverage GPT-4.1’s improved multi-language, diff, and instruction-following skills in a familiar, VS Code-like environment (Dr. Lee's Blog).

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