> ## Documentation Index
> Fetch the complete documentation index at: https://012e27a-docs-2.manicule.dev/llms.txt
> Use this file to discover all available pages before exploring further.
> For every page in one file, fetch https://012e27a-docs-2.manicule.dev/llms-full.txt (large).
> To search and read these docs as tools, connect the MCP server at https://012e27a-docs-2.manicule.dev/api/mcp.
> Every agent surface: https://012e27a-docs-2.manicule.dev/.well-known/llms-manifest.json

# Multi-File Visual Diff Viewer (/desktop/diff-viewer)

<!-- agent-signals: reading_time_min: 1 · est_tokens: 369 · updated: 2026-11-12 -->
Related: [Desktop Workspace Overview](/desktop/overview.md), [Agentic Canvas Mode](/desktop/agentic-mode.md), [Code Editor & Highlight-to-Ask AI](/desktop/code-editor.md), [Transparency Dock & Approval Gates](/desktop/transparency.md), [Integrated PTY Terminal](/desktop/terminal.md)

> Review AI edits with hunk-by-hunk accept/reject and instant checkpoint rollback.

When an agent touches several files, review comes before merge. The diff viewer is where you
decide what survives.

## Review modes

* **Unified or split**: inline diffs or side-by-side comparison.
* **Syntax-aware colour**: green additions, red deletions, and word-level highlights for
  changed characters.
* **Hunk-by-hunk approval**: accept (`✓`) the improvements you want and reject (`✗`) the rest.

## Review actions

<Tabs>
<Tab title="Per hunk">Accept or reject an individual block of changes. Ideal for long files where only part of
the agent's edit is useful.</Tab>

  <Tab title="Per file">
    * **Accept file** applies every change in the current file to your working directory.
    * **Discard file** restores it to its exact pre-prompt state.
  </Tab>

<Tab title="Whole session">Click **Rollback to checkpoint** in the toolbar to return the entire working tree to the
state before the prompt was submitted.</Tab>
</Tabs>

## Checkpoints

Every completed agent task records an ephemeral **Git checkpoint snapshot**:

* Checkpoints act as a local undo stack.
* They do not pollute your permanent commit history.
* You can roll back at any time, then keep working forward from that state.

<Note title="Checkpoints are not commits">Nothing enters your Git history until you commit. Use the
[PTY terminal](/desktop/terminal) or your normal Git workflow when you are ready.</Note>