Software Engineer, Agent Harness Engineering San Francisco

Our mission is to automate coding. The first step in our journey is to build the best tool for professional programmers, using a combination of inventive research, design, and engineering. Our organization is very flat, and our team is small and talent dense. We particularly like people who are truth-seeking, passionate, and creative. We enjoy spirited debate, crazy ideas, and shipping code.

As a Software Engineer on the Agent Harness team at Cursor, you’ll build the core agent behavior and capabilities that power agent experiences across Cursor products. This spans agent orchestration, tools, guardrails, and model behavior tuning—designed as a platform that Cursor engineers can extend and depend on.

Your work will also define the default Cursor agent experience ("Auto"), where users trust us to make the right model choices under real-world constraints.

• Advancing the agent harness (agent loop, tools, prompts, execution environment, capabilities) used across Cursor products. This would shape and empower experiences like multi-agent coordination.
• Improving the default Cursor agent experience (the “Auto” model setting): making smart model choices based on user needs, model capabilities, and cost appetite.
• Shaping the default Cursor agent’s personality.
• Launching new models on Cursor end-to-end — partnering with foundational model providers and our research team on integration, evaluation, and rollout.

• You have built complex agentic products or infrastructure.
• You have strong software engineering fundamentals and enjoy shipping production systems.
• You have taste and strong opinions on model and agent behaviors. You stay up-to-date and informed on emerging research and industry trends.
• You make good calls in the gray area: weighing data, user experience, and product taste when there isn’t a single “right” answer.
• Experience building eval datasets or frameworks to understand and improve the performance of AI systems is a plus.
• Experience building products or tools used by other engineers is a plus.

Anysphere, Inc. provides equal employment opportunities to applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, or disability.

We invite all applicants to voluntarily self-identify their race, ethnicity, and gender. Submission of the information on this form is strictly voluntary and refusal to provide it will not subject you to any adverse treatment. Information obtained will be retained in a confidential file and separate from personnel records. This information may only be used in accordance with the provision of applicable federal laws, executive orders, and regulations.

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