> ## Documentation Index
> Fetch the complete documentation index at: https://docs.entire.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> Learn what checkpoints are, why they matter, and how Entire captures them.

## What is a checkpoint?

A checkpoint is an addressable record of the context behind an AI-assisted change. After you [enable Entire](/quickstart) in a repository, the [CLI](/platforms/cli) uses Git hooks and [agent hooks](/agents/overview) to capture session data as you work. When you or your agent commit, Entire saves that captured context as a checkpoint and links it to the commit.

## Why checkpoints matter

* Review agent work without guessing what happened
* Trace a commit back to the prompt, transcript, and session that produced it
* Understand what changed, why it changed, and who edited what
* Search past agent work later

## How checkpoints connect to Git

Each checkpoint has a 12-character ID. Entire adds that ID to the commit message with an [`Entire-Checkpoint` trailer](/glossary#entire-checkpoint) and stores checkpoint metadata on the [`entire/checkpoints/v1` branch](/security#where-your-data-lives).

Your normal Git history stays clean. Entire does not add extra commits to your working branch.

## What a checkpoint stores

A checkpoint stores the available context behind the change, including:

* the linked Git commit
* the agent session or sessions behind the change
* prompts and transcript
* tool activity
* changed files
* token usage, when available
* [AI attribution](/guides/sessions/sessions-in-entire-io#files-and-attribution) for the changed lines in the checkpoint

## Where to review checkpoints

You can review checkpoints from the CLI or in Entire.io.

Use [Review Checkpoints](/guides/checkpoints/review-checkpoints) to choose the right surface and see the common review flows. Use the [CLI reference](/cli-reference/checkpoint) when you need exact command syntax.