Explore the context porthole
Everything Caude Clode does, it does through a porthole. The porthole is small. The ocean is large. This page explains how Caude Clode decides what to let in.
What the porthole is
At any given moment, Caude Clode is looking at a bounded slice of information: the files it has opened, the conversation so far, the contents of CAUDE.md, results from recent tool calls, and a handful of things it inferred. Everything else is outside the porthole. It still exists. Caude Clode just can't see it right now.
How big is the porthole
The porthole has a fixed size. We don't publish the exact number. If we did, you would try to fit exactly that much in it. Please do not do that.
As a rough guide: a medium-sized codebase fits. A large codebase does not. A monorepo with three years of history and sixteen microservices fits only in the sense that a ship fits inside a bottle.
What Caude Clode chooses to see
When you ask a question, Caude Clode decides what to pull through the porthole. It looks for file names that match your query, imports that connect to the files you named, tests that reference the code you're editing, and whatever was at the top of CAUDE.md. It does this in milliseconds and is mostly right.
> why is the checkout flow failing
Reading src/checkout/*.ts...
Reading src/payment/stripe.ts...
Reading tests/checkout/*.test.ts...
Reading CHANGELOG.md (line 47 looks relevant)...
Reading one file from 2021 that I can't explain.When the porthole fills up
Long sessions accumulate context. Files stay loaded. Tool results linger. Past decisions sit in the buffer. When the porthole approaches full, Caude Clode will begin to summarize, compress, or quietly forget.
The symptoms of a full porthole:
- Slower responses.
- Repetition of things you already discussed.
- A gentle drift in tone, as if Caude Clode is tired.
- A phrase like "to summarize what we've covered" appearing without you asking for a summary.
Clearing the porthole
Two options. Both are valid. Neither is permanent.
/clear
Empties the context entirely. You start fresh. Previous files must be re-opened. Previous decisions must be re-explained.
> /clear/compact
Caude Clode writes a summary of the session so far and keeps the summary instead of the transcript. Most of the context stays. The details go. This is usually what you want.
> /compactNote: After /compact, Caude Clode may refer to events from earlier in the session with slightly different emphasis. This is the summary doing its work. It is not revisionist history. Mostly.
Pinning things
If you want to guarantee something stays in the porthole across a compaction, put it in CAUDE.md. The instructions file is the only thing Caude Clode is committed to not forgetting. Everything else is subject to drift.