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

# Chat Integrations (aka MCP Servers)

> Connect tools like HubSpot, Slack, Notion, and Linear to Hercules so it can read and act in them while you chat and build. Personal to you.

Chat Integrations (also known as MCP servers) let Hercules read and act in the tools you use, like HubSpot, Slack, Notion, and Linear, while you chat and build. Pick from the catalog or add your own. The same integrations work in the App Builder and in [Chat](/docs/agents/chat).

<Warning>
  Chat Integrations are for Hercules, not for your app. Your published app cannot use them. To let
  your app read or write data in a service, connect it in [App Integrations](/docs/apps/app-connectors).
</Warning>

<div className="screenshot ocean">
  <img src="https://mintcdn.com/zeus-0f6dadbf/z4_tZc5L3OISSRTH/images/ai/chat-connectors-catalog.png?fit=max&auto=format&n=z4_tZc5L3OISSRTH&q=85&s=519a00e4738166e503a3d200cebcb2b4" alt="Chat Integrations catalog showing connectors like Linear, Notion, Sentry, Stripe, GitHub, and Slack with categories and an Add Custom Connector button" width="1024" height="501" data-path="images/ai/chat-connectors-catalog.png" />
</div>

### How do I use Chat Integrations?

1. Connect the integration
2. Tell Hercules what you want to do in that tool

<div className="screenshot ocean">
  <img src="https://mintcdn.com/zeus-0f6dadbf/z4_tZc5L3OISSRTH/images/ai/chat-connectors-step-read-answer.png?fit=max&auto=format&n=z4_tZc5L3OISSRTH&q=85&s=a465818eb07bd80d7750da45efbe58d7" alt="Hercules fetching a Notion page through the Notion connector and reading its content to build a website" width="906" height="576" data-path="images/ai/chat-connectors-step-read-answer.png" />
</div>

### How do I set up Chat Integrations?

1. Open an app, then click **Chat Integrations** in the sidebar
2. Choose the service you want to connect
3. Sign in to that service

### Can I control when Hercules uses an integration?

Yes. Turn integrations on or off from the chat input.

Click **+** → **Integrations** and toggle on the ones you want. To point Hercules at one integration, type **@** and pick it.

<div className="screenshot mint">
  <img src="https://mintcdn.com/zeus-0f6dadbf/z4_tZc5L3OISSRTH/images/ai/chat-connectors-chat-menu.png?fit=max&auto=format&n=z4_tZc5L3OISSRTH&q=85&s=38d355258275ecb9aaa99e786f20bdea" alt="Chat input menu with Integrations expanded, showing toggles for Linear, Notion, and Slack" width="922" height="436" data-path="images/ai/chat-connectors-chat-menu.png" />
</div>

### What's the difference between Chat Integrations and App Integrations?

Both connect the same kinds of services. The difference is who uses the connection.

| Feature | Who uses it | Example |
| - | - | - |
| **Chat Integrations** (this page) | Hercules, while you chat and build | "Read my Notion spec and build the app" |
| [**App Integrations**](/docs/apps/app-connectors) | Your published app, after you publish it | "Post to Slack when a new order comes in" |
| [Hercules MCP](/docs/hercules-mcp) | Other AI assistants (ChatGPT, Claude...) | "Use Hercules from inside ChatGPT" |

Connecting a service in one place does not connect it in the other. If you want Hercules to read Slack and your app to post to Slack, connect Slack in both.

### Are Chat Integrations shared with my teammates?

No. Chat Integrations are personal to you. Teammates in your organization cannot see or use yours.

### How do I add a custom integration?

1. Open **Chat Integrations**
2. Click **Add custom integration**
3. Paste in the MCP server URL (the address of the service's AI connection)

Hercules will then prompt you to authenticate.

<div className="screenshot purple">
  <img src="https://mintcdn.com/zeus-0f6dadbf/z4_tZc5L3OISSRTH/images/ai/chat-connectors-add-custom.png?fit=max&auto=format&n=z4_tZc5L3OISSRTH&q=85&s=424893c121bfff98f2b3ddbd671b087b" alt="Add custom connector dialog with an MCP Server URL field, an Advanced section, and Cancel and Add buttons" width="870" height="510" data-path="images/ai/chat-connectors-add-custom.png" />
</div>

Custom integrations appear under the **Custom** category in the catalog.

### How do I control Chat Integration permissions?

Open a connected integration's detail page to see its tools, grouped as **Read** or **Write**. For each tool, set:

| Permission | What it does |
| - | - |
| **Always allow** | The Agent can call the tool without asking |
| **Ask for approval** | You approve each call before it runs |
| **Blocked** | The Agent cannot call the tool |

Write tools default to **Ask for approval**. Read tools default to **Always allow**. Change permissions per tool, or set them for a whole section at once.

### Additional FAQ

<AccordionGroup>
  <Accordion title="Where do I find the catalog?">
    You can open the same catalog from three places:

    | Location | How to get there |
    | - | - |
    | **Hercules App Builder** | Open an app → **Chat Integrations** in the sidebar |
    | **Dashboard** | **Integrations** in the left sidebar |
    | **Settings** | **Settings** → **Chat Integrations** |
  </Accordion>

  <Accordion title="Do Chat Integrations work across all my apps?">
    Yes. Once you install and enable an integration, Hercules can use it in every app you build in
    that organization. Toggling an integration on or off from chat or the integration detail page
    applies everywhere, not only the current app.
  </Accordion>

  <Accordion title="What is the difference between disable, disconnect, and remove?">
    **Disable** turns an integration off for Hercules but keeps it installed. **Disconnect** signs you
    out of an OAuth integration while keeping it installed. **Remove** uninstalls the integration and
    deletes stored credentials. You can add it again from the catalog later.
  </Accordion>

  <Accordion title="What if I do not see the integration I need?">
    Click **Request integration** at the bottom of the catalog. Tell us which service you want and we
    will consider adding it. You can also add a custom integration with the server's URL.
  </Accordion>

  <Accordion title="Is there a limit on how many integrations I can use at once?">
    You can enable as many as you want. Hercules works best when you enable only the ones you need.
  </Accordion>

  <Accordion title="What does it cost?">
    Connecting and using Chat Integrations is free. Messages where Hercules uses an integration use AI
    credits the same as any other build chat. See [AI Credits](/docs/platform/billing/ai-credits) for
    details.
  </Accordion>

  <Accordion title="Are my credentials safe?">
    Tokens and OAuth secrets are encrypted at rest. Hercules never shows stored secrets again after
    you save them. OAuth sign-in happens in your browser, the same as connecting any other account.
  </Accordion>
</AccordionGroup>


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