In short
The written record of how a system works. Here, the agent keeps it current, so the person who was not in the room can take over.
Documentation is what makes software transferable. Without it, a system belongs to whoever built it. With it, anyone can read how it works, why it was built that way, and what to do when it breaks.
Most documentation rots because writing it is a chore nobody is paid for. We solve that by making it the agent's job. After every change, the agent updates the docs. After every incident, it records what happened and what was changed. The docs are always current because keeping them current is part of the instructions.
This is also why hand-off works. When a team takes the keys on day 90, the documentation is already complete, because it was never allowed to fall behind.
Example
What it looks like.
A change log entry the agent wrote:2026-08-17. The deploy fired but production did not update. Added a check that waits for the new build and forces a deploy if none appears. Runs after every publish.
Related
Read next.
- instruction fileThe Markdown file that tells an agent who it is, what it owns, and what it may never do. The agent's job description, readable by the agent.Read the definition
- hand-offDay 90. We hand over the keys, the instructions and the files. Your team already runs it. Nothing is held.Read the definition
- portabilityYour agents are files. They move to any harness, any model, any host. Leaving is copying a folder.Read the definition