# How Lee Robinson actually uses coding agents

ML at SpaceX, ex-Cursor, Vercel

**If you take one thing:** `Plan mode`, before every long agent run. he plans each change with the model in Cursor, then hands it to a cloud agent and walks away. That is how he built a whole Rust library without writing code by hand.

- **Agent:** Grok Bot (app) ([source, 2026-08-27](https://x.com/leerob/status/2092786147156246906))
- **Agent:** Cursor (web) ([source, undated](https://leerob.com/cursor))
- **Model:** Claude Opus 4.5 ([source, 2025-12](https://leerob.com/pixo))
- **Model:** GPT-5.1-Codex-Max ([source, 2025-12](https://leerob.com/pixo))
- **Review:** Reviews most of the code and tests it; Bugbot reviews every PR ([source, 2025-12](https://leerob.com/pixo))
- **Harness:** Always-running Grok Bots on their own cloud computer, connected to his X and Gmail ([source, 2026-08-22](https://x.com/leerob/status/2091265397056016677))
- **Rules file:** AGENTS.md (pixo), added only after the model made mistakes ([source, 2025-12](https://leerob.com/pixo))
- **Skills:** next-best-practices, vercel-react-best-practices ([source, 2026-03-16](https://github.com/leerob/march-arena/tree/95e10f33b695f8c535aedd6b27f88ba8fadbf6cb/.cursor/skills))

## In their words

> I started by using Bot for personal tasks instead of work things, but it quickly took over the majority of my tokens.

> I'm very opinionated about products for engineers, and a heavy user of Cursor myself, so I often gathered customer feedback and made sure we were building the right thing.

> The spend was about 70% Opus, 30% Codex due to their API pricing.

> Throughout the project, I flipped between Opus 4.5 and GPT-5.1-Codex-Max. Both performed very well, although I used them differently. For example, Codex performed better for long-running tasks, while Opus was significantly better at writing.

> It’s worth noting that I did review most of the code and tested changes both manually and with automated tests. I also had Bugbot review all my PRs (example).


Archetype (our label): Orchestrator. Newest source: 2026-08-27.
Card: https://www.prehistoriq.com/stacks/leerob/ · Data: https://github.com/prehistoriq/stacks/blob/main/data/stacks/leerob.json