Reviewing diffs

Every edit to an existing file stops and shows you a unified diff before anything is written. This is the one protection that does not depend on your approval mode.

What you see#

 ← Editing  src/auth/login.ts                        +6 −0    export async function login(req: Request) {+    /**+     * Exchanges a set of credentials for a session cookie.+     */     const body = await req.json();  Esc reject · ↑↓ scroll                    Enter apply

The header names the action and the file, and counts the lines added and removed. Added lines carry +, removed lines −.

Key	Action
`Enter`	Apply the edit
`Esc`	Reject it
`↑` `↓`	Scroll, when the diff is longer than the screen
`PgUp` `PgDn`	Scroll a screen at a time
`Home` `End`	Jump to the top or the bottom

The hint row along the bottom shows only the two answers, because they are the decision; the scrolling keys are there whether or not it has room to say so.

Which tools stop here#

Tool	What it does	Approval
`create_file`	Creates a new file with the provided content. Pass an empty string to create an empty file.	Pauses on a unified diff. Nothing is written until you approve it.
`write_file`	Overwrite an existing file.	Pauses on a unified diff. Nothing is written until you approve it.
`edit_file`	Replace text inside an existing file. oldText must match exactly one place in the file, or the edit is refused so the wrong occurrence is never changed.	Pauses on a unified diff. Nothing is written until you approve it.

Creating a new file is also shown before it is written — an empty file is a valid thing to create, and you should still get to see it coming.

Rejecting is a normal move#

Esc is not an error and not a cancellation. The agent is told the edit was declined and continues from there, so the useful pattern is to reject and immediately say what you wanted instead:

Not quite — keep the existing return type and only add the docstring.

The rejected edit stays in the conversation as context, so you do not have to re-explain the whole task.

To stop the turn entirely rather than decline one edit, use CtrlC. Esc rejects what is in front of you; it does not stop the agent.

Reading a long diff#

Diffs longer than the screen scroll with the arrow keys. Two habits help:

Check the counts first. +6 −0 on a docstring is expected. +6 −40 is worth reading closely.

Check the file path. It is the fastest way to catch an edit aimed at the wrong file — a test instead of the source, or a generated file that will be overwritten.

Why the review is here and not in git#

An agent that writes first and lets you inspect afterwards is faster right up until it is wrong, and then you are reading git diff reconstructing what happened and why. Reviewing before the write means the change never lands, the agent learns immediately, and your working tree is never in a state you did not choose.

When it does not work#

A diff appeared for a file you did not expect — Reject it. The agent inferred the wrong target; say which file you meant.

The diff is enormous — Reject and narrow the request. A turn that produces a several-hundred-line diff has usually misunderstood the scope, and reviewing it properly costs more than redoing the ask.

No diff appeared and a file changed anyway — That was a shell command, not an edit tool. Check your approval mode with /status.

Next#

Approval modes — the other gate
Keyboard — every key

Added in woopcode@0.6.0