AI Coding Giants Windsurf and Cursor Face Off Over Shared Prompts

The coding landscape is undergoing a rapid transformation due to AI, with U.S.-based startups leading the charge. Companies like GitHub and OpenAI have introduced AI-powered tools, Copilot and Codex, respectively, which are designed to help developers write, optimize, and debug code more efficiently. These tools allow developers to focus on complex problem-solving, while AI handles repetitive tasks. Additionally, startups like Tabnine and DeepCode offer AI solutions that provide real-time code improvements and bug identification, enabling developers to create robust applications faster. As AI continues to advance, these companies are redefining software development, streamlining workflows, and making coding accessible to a wider audience.

But two companies generating the most buzz in the coding ecosystem right now are Windsurf and Cursor.

The rivalry between Windsurf and Cursor is a fascinating one because it reflects a broader philosophical divide in the development of AI tools: adaptability versus autonomy. Windsurf takes the approach of adaptability; its core strength is learning from the user and tailoring suggestions to fit their unique style and needs. This makes Windsurf incredibly powerful for developers who want a tool that evolves with them over time and grows more intelligent based on their habits. On the other hand, Cursor embraces autonomy; it seeks to reduce the developer’s input as much as possible, letting the AI take control and automate as many parts of the coding process as it can. Cursor’s vision is a future where developers spend less time writing boilerplate code and more time solving complex, high-level problems. In some ways, Cursor is pushing the envelope by reducing human intervention, while Windsurf leans more toward a balance of assistance and evolution, empowering the developer without taking full control.

Therefore, both have emerged as innovators in this space. But recently, a curious discovery has raised some eyebrows in the tech community: both companies appear to be using nearly identical system prompts to power their coding tools.

“You are pair programming with a USER to solve their coding task. The task may require … or simply answering a question.”

This exact wording can be found in both Windsurf and Cursor’s system prompts, setting the tone for their AI to assist developers with coding tasks. But the real question is, how did this happen? Are these prompts a coincidence, or is there something more at play here?

This “weird” discovery was first posted by Matt Ambrogi on X. 

It’s the same structure, the same language, and it seems to serve the same purpose, i.e., to tell the AI that it is assisting a developer, much like a pair programmer would. The similarities don’t stop there; even the majority of the features, from file editing tool commands to the details in the code editing section, are the same, Ambrogi noted in a series of posts.

Both companies are vying for dominance in a market that is quickly becoming crowded with AI-powered development tools. And the question looms: is this a case of shared transformation, or has one company copied the other’s playbook?

Kevin Hou, Windsurf’s head of product engineering, was quick to point out that Windsurf launched on November 13th with the prompt in question. This was before Cursor launched agent mode on November 24th, utilizing Windsurf’s prompting to expedite their process.

Some believe that Cursor is the one doing the borrowing. After all, Windsurf’s focus on context-aware coding assistance and its natural language interface were first to market, and its system prompt has been a key part of the company’s brand. The similarity in the prompts could be viewed as a sign that Cursor was trying to replicate the magic that Windsurf created.

To be fair, some developers have shrugged off the controversy, arguing that system prompts aren’t proprietary. After all, you can’t copyright a sentence, or can you? And in the high-stakes world of AI startups, what constitutes theft versus inspiration is a blurry, gray zone.

What makes the Cursor–Windsurf rivalry even more explosive is the shadow of OpenAI, the crown jewel of the AI boom, looming over both startups but in very different ways.

On the surface, it appears OpenAI has chosen a side. Windsurf is reportedly in acquisition talks with OpenAI for nearly $3 billion, according to Reuters. That’s a massive bet on Windsurf’s vision of adaptable, human-in-the-loop AI coding tools and a huge validation of its approach to developer-first interfaces.

But beneath the headlines, OpenAI may have already funded Windsurf’s biggest rival.

In February 2024, Cursor quietly received funding from OpenAI’s Startup Fund, the same vehicle that has previously backed Anthropic and Harvey AI. While the amount remains undisclosed, the partnership was enough to grant Cursor early access to GPT-4-turbo and other powerful OpenAI APIs. This let Cursor leapfrog competitors in launching advanced features like agent-based editing, inline suggestions, and full-repo context awareness, many of which closely mirrored Windsurf’s own capabilities.

This looks like a classic Silicon Valley double play: back one company to move fast and push the limits, then buy the one with defensible product-market fit and developer love. But to others, it’s a murkier ethical issue: Did OpenAI give Cursor privileged access to tech and prompting strategies that helped it “reproduce?”