# Editing Toolkit
Use the Editing Toolkit to apply content changes from your own AI agents, chat interfaces, backend workflows, or scripts to CKEditor 5 documents. Your code or service produces the revised content, and the toolkit compares it with the original so users can review and accept the changes in the editor.
The toolkit has two components:
* [Compare](#compare) finds the differences between the original and revised content and applies them, directly or as suggestions. You can also use Compare without AI, for example to apply updates from a script or an HTML version edited elsewhere.
* [Coauthor](#coauthor-ckeditor-mcp) lets AI agents read and edit documents on the server through the Model Context Protocol (MCP). Your backend can also call the same tools over REST without using an AI model.
Both components treat each difference as a separate, granular change. For example, a reworded phrase can appear as an individual change for users to review, be recorded as a Track Changes suggestion, or be applied to the content directly.
In the video, a backend job runs two agents over several documents. The second agent checks the work of the first one, and a person reviews their suggestions. The [backend agent workflows](use-cases/editing-toolkit-backend-agents.md) guide describes this setup.
## Highlights
* Have an agent update a document on the server and leave [Track Changes](../collaboration/track-changes/track-changes.md) suggestions for a person to review later. [Coauthor](#coauthor-ckeditor-mcp) runs the editor on the backend, so nobody needs to have the document open in a browser.
* Connect your existing AI chat to the document and let users review its edits where they appear, using the [Proposed changes UI](compare/editing-toolkit-proposing-changes.md). Users can apply or reject individual changes, or handle all of them at once.
* Let people keep editing while your agent works. [Compare](compare/editing-toolkit-comparing-documents.md) merges the agent’s changes with the edits made in the meantime, including other users’ edits in [real-time collaboration](../collaboration/real-time-collaboration/real-time-collaboration.md).
> **Note**
>
> For an off-the-shelf product that combines CKEditor 5 with AI features, an agent, and an AI service, see the [CKEditor AI](../ai/ckeditor-ai-overview.md) guide. You can also use CKEditor AI with the Editing Toolkit, as described in the [Using with CKEditor AI](use-cases/editing-toolkit-with-ckeditor-ai.md) guide.
## Compare
[Compare](compare/editing-toolkit-comparing-documents.md) provides document comparison APIs and the Proposed changes UI for CKEditor 5. Your integration takes a snapshot of the document, processes its content with your code or service, and passes the revised content back to Compare to compute and apply the differences.
* [Comparing documents](compare/editing-toolkit-comparing-documents.md) – The `DocumentCompare` API takes a snapshot of the document, lets your code or service process it, computes the differences, and applies them as granular changes or suggestions.
* [Proposing changes](compare/editing-toolkit-proposing-changes.md) – The Proposed changes UI lists the computed differences in a panel before they appear in the document. Users can apply or reject each change, or record it as a Track Changes suggestion for collaborators to review later.
> **Unlock this feature with the Custom Plan**
>
> Try this feature for **free during your trial** — no credit card required.\
> After the trial, it’s available as a premium add-on in the [CKEditor Custom Plan](https://ckeditor.com/pricing/).
>
> [Sign up for a free trial ](https://portal.ckeditor.com/checkout?plan=free)[Contact sales](https://ckeditor.com/contact-sales/)
## Coauthor (CKEditor MCP)
[Coauthor](editing-toolkit-coauthor.md) is the backend part of the toolkit. It exposes documents to AI agents through MCP and runs a CKEditor 5 instance on the server. Agents use its tools to read, edit, and verify content. Backend code can call the same tools over REST. Compare applies changes inside that server-side editor, so agents can work without anyone having the document open in a browser.
The server-side editor runs the same editor bundle that you upload to Cloud Services, so it uses the same features, plugins, and configuration as the editor your users see. Coauthor works with both real-time collaboration and non-real-time setups.
> **Available in early access**
>
> Contact us to enable Coauthor in your trial or existing environment. We will help you with the server-side setup.
>
> [Contact us ](https://ckeditor.com/contact-sales/)[View plans](https://ckeditor.com/pricing/)
## Use cases
These guides cover integrations with agents, chat interfaces, backend services, and scripts. The agent app, custom chat, and backend workflow guides use Coauthor.
* [Working from agent apps](use-cases/editing-toolkit-agent-apps.md) – Start editing tasks in an app such as Claude or ChatGPT and review the results in CKEditor 5.
* [Custom chat implementation](use-cases/editing-toolkit-custom-chat.md) – Build your own AI features: Compare handles the review in the editor, and Coauthor helps your agent produce content the editor accepts.
* [Backend agent workflows](use-cases/editing-toolkit-backend-agents.md) – Run server-side flows, for example one agent drafts and a second one reviews.
* [Using with CKEditor AI](use-cases/editing-toolkit-with-ckeditor-ai.md) – Let the CKEditor AI Document Processing endpoint produce the changes and the toolkit propose them.
* [Scripts and external versions](use-cases/editing-toolkit-deterministic-scripts.md) – Review changes from scripts or compare an updated Word file with the current document.
## Related features
* [Track Changes](../collaboration/track-changes/track-changes.md) – Apply toolkit changes as suggestions that users can accept or reject.
* [CKEditor AI](../ai/ckeditor-ai-overview.md) – A complete AI stack with ready-made editor features, an AI agent, and an AI service.
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Full index of the CKEditor 5 documentation: [llms.txt](../../../llms.txt)