Summary
Theo of t3.gg walks through three markdown-based agent skills that have become central to how he builds software: Sole Loop, Full Send, and Full Stop. Rather than inventing the skills up front, he turned behaviors he kept repeating into reusable instructions. Almost half of his threads in T3 Code now use at least one of them, and he says the threads that end up merged into main almost always do.
The video explains how he keeps skills, MCPs, and authentication synced across multiple machines using a single repo called fleet, and how he organizes skills by tool and by machine. He also covers supporting skills for filing and babysitting pull requests and for leaving agent comments that disclose which model is responding on his behalf.
A key idea is treating the T3 Code sidebar as an inbox: every thread should either be working or be gone. Theo describes settling threads once work is merged, auto-archiving on merge, and the optional Working section that keeps in-progress threads out of the way. The goal is to reduce slop in pull requests and make merging with confidence as fast as possible. A sponsor segment on WorkOS covers enterprise SSO, MCP auth, and the authmd standard for agent sign-ups.
📺 Source: Theo – t3․gg · Published October 26, 2026
🏷️ Format: Workflow Case Study
