1.6
Sessions And The Commands That Matter
Why this exists
There are a handful of commands you'll use every single day, and they're all one word with a slash in front. Learn them now, in ten minutes, and you'll use them for years. Skip them and you'll spend months doing manually what a five-character command does instantly.
This lesson is the controls. Next week explains what they're doing and why it matters — that's 2.2. For now, just learn where the buttons are.
The idea
A session is one conversation, and it has a weight.
Every message you send, every file it reads, every answer it gives — all of it stays in the session and adds up. There's a limit to how much fits, and long before you reach the limit you'll feel it: slower answers, vaguer answers, it forgetting things you said earlier.
You don't need to understand why yet. You need the controls.
| Command | What it does |
|---|---|
/help |
Lists everything available. Your way out of any "what was that command" moment. |
/context |
Shows how full the session is, and what's filling it |
/compact |
Squashes the conversation down, keeps what matters |
/clear |
Wipes it. Fresh start, same folder |
| Plan mode | It works out what it would do and shows you, before doing anything |
Three habits, and they'll carry you a long way:
Check /context when it starts feeling dim. Slower or vaguer answers are a symptom with a number behind it. Look at the number rather than guessing.
/clear when you change topic. Not because you have to — because the previous conversation is now noise competing with your new question. Clearing costs you nothing. There's no penalty, nothing lost, no progress forfeited.
Plan mode before anything that changes real files. It tells you what it intends to do and waits. You read it, and either say go or correct the plan while correcting is still cheap. This is the single most useful habit in the whole course and almost nobody builds it, because saying "just do it" is faster right up until the once in twenty times it isn't.
One thing that'll save you confusion: a new session is not a new project. Clearing wipes the conversation, not the folder. Your files are untouched, and the next session is standing in exactly the same place. The conversation is temporary; the folder is permanent. That distinction is most of what makes Level 3 make sense.
Do
Use the sandbox folder from 1.3.
- Run
/help. Skim it. You're not learning it, just seeing what exists. - Have a real back-and-forth with Claude about the files in
sandbox— ten messages or so. Ask it to change things, ask follow-ups. Build up some history. - Run
/context. Write down the number and what's filling it. - Run
/compact, then/contextagain. Write down the new number. - Run
/clear. Then askwhat files are in this folder?— confirm for yourself that your files are untouched. - Turn on plan mode. Ask for something that would change more than one file. Read the plan. Then reject it and ask for something different.
- Turn plan mode off, ask for the same thing, and notice what's different about how that felt.
- Write
commands.md— the five, each with one line in your own words about when you'd use it.
Step 6 is the habit worth building. Reading a plan and rejecting it, once, deliberately, is what makes you reach for plan mode later when it actually matters.
Done when
Never do
Don't run something that changes multiple files without plan mode. Not this week, not while everything is still novel. Reading the plan takes fifteen seconds and it's the cheapest possible place to catch a misunderstanding — before it's happened, rather than after.