Codex Core Agent — Applied AI Engineer

Jobzhr; San Francisco, Northern (CA, KY); Hybrid; USD 230,000 - 385,000; Full time

Job summary

OpenAI is seeking applied AI engineers to advance Codex agents from demos to dependable tools. You will improve performance on real software tasks, closing the gap between research and production and delivering measurable gains in solve rate and user value.

You’ll collaborate with research, infrastructure, and product to ensure agents are powerful, steerable, and reliable in practice, turning model potential into real-world usefulness for users in San Francisco and beyond.

Qualifications

• Experience building or shipping machine learning or LLM-powered products.
• Strong in Python and comfortable with modern ML tooling.
• Experience with model evaluation, fine‑tuning, or prompt design.
• Think in terms of systems and user outcomes, not just model metrics.
• Enjoy debugging messy, real-world failures and turning them into improvements.
• Want to work in the layer that turns research and model potential into systems that actually work for users.

Responsibilities

• Design and iterate on agent behaviors across real-world coding tasks and long-horizon workflows.
• Work closely with research to develop and run evals to measure agent performance, regressions, failure modes, and edge cases.
• Improve performance through prompting, tool-use strategies, context construction, and model-facing experimentation.
• Analyze failures in production and systematically improve robustness and reliability.
• Build feedback loops and data systems that get better real-task data into evaluation and research.
• Work with product teams to shape user-facing agent experiences and the interfaces the agent depends on.
• Help define what “good” looks like for agents completing complex tasks end-to-end.

Skills

Python

ML tooling

model evaluation

prompt design

systems thinking

debugging real-world failures

LLM-powered products

Tools

Agent frameworks

Developer tooling

Code generation models

Job description

OpenAI is seeking applied AI engineers to advance Codex agents from demos to dependable tools. You will improve performance on real software tasks, closing the gap between research and production and delivering measurable gains in solve rate and user value.

You’ll collaborate with research, infrastructure, and product to ensure agents are powerful, steerable, and reliable in practice, turning model potential into real-world usefulness for users in San Francisco and beyond.