A thinking partner has to remember you. So the question I most wanted answered was simple. Is Claude getting better at working with me?
The straight answer is that the model doesn't change between sessions. It doesn't remember last Tuesday. What carries over is whatever got written into files: a rulebook it reads at the start, and a folder of short notes.
That's the whole mechanism. It works better than it sounds, and it needs looking after.
What works
I have 69 notes. When I correct Claude and it matters, Claude saves a note: what I said, why, and when to apply it. The next session starts with that note loaded.
41 of the 69 are corrections and preferences. Things like "verify before you tell me it works" and "don't hand me a check you could run yourself". They are still being added. Claude made 36 edits to the notes from my laptop in the first ten days of October alone.
This is real. A new session with my notes behaves differently from a new session without them.
What needs looking after
Then I read the notes properly, start to finish.
They contradicted each other. One note set out the look of my client documents, including an accent colour. My brand rules, in a different file, ban that exact colour. Both were loaded every session. Which one won depended on which Claude noticed first.
They went stale. One note said to revisit a decision "around late May". It was October. The note was still there, still being read, still describing a plan that never happened.
They pointed at things that had moved. My rulebook told Claude to read a memory folder that doesn't exist on my laptop. It existed on my other computer, at a different address.
The same problem broke my skills. I keep one setup synced across two computers. 52 of the 135 skill links on the laptop were dead, because they were written as addresses on the other machine.
None of this produced an error. Claude just worked with what it could find.
Treat it like a handbook
A staff handbook that nobody edits ends up with three policies on the same thing and a fire exit that was bricked up last year. The notes are the same. They need an editor, and the editor is you.
The fix took minutes once I looked. Resolve the contradiction. Rewrite the stale note to say what's true now. Point the rulebook at a folder that exists. Use addresses that work on both machines.
The numbers in this series all come from one audit of my own Claude sessions. Read the full report →