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

# Connect with ChatGPT

> Add AI Baseline as a custom MCP connection in ChatGPT and query S&P 500 SEC filings.

Connect ChatGPT to AI Baseline to retrieve SEC filing evidence and use it in your
answers. Add the remote MCP server as a custom plugin, authorize it, and select it
in your conversation.

These steps use the S\&P 500 knowledge base as an example. To connect another
knowledge base, use its supplied `https://mcp.ai-baseline.dev/{org}/{base}` URL,
a matching connection name, and a key with access to that base. The same domain
can serve several separate bases; [the URL selects the base](/guides/knowledge-bases).

## Before you start

Have an AI Baseline API key with access to the S\&P 500 collection. Use ChatGPT on
the web with permission to add custom MCP servers. Your account and workspace
policies determine whether this option is available; a workspace administrator
may need to enable it.

These steps follow OpenAI's
[custom MCP server setup](https://developers.openai.com/api/docs/guides/custom-mcp-server).

## Add the connection

1. Open [ChatGPT Plugins](https://chatgpt.com/plugins).

2. Select **+ → Add custom MCP server**.

3. Name the connection **AI Baseline S\&P 500**. Under **Connection**, enter this
   exact server URL:

   ```text theme={null}
   https://mcp.ai-baseline.dev/baseline/sandp500
   ```

4. Choose **OAuth** for authentication. Leave optional client ID and client secret
   fields empty for automatic client setup. AI Baseline supports both
   [CIMD and DCR](/connect-mcp#client-registration).

5. Review the connection details and the permission warning, then select
   **Create as a plugin**. Review the discovered tools and install the resulting
   plugin from your personal or workspace plugins.

6. Complete authorization when prompted. On the AI Baseline sign-in page, enter
   your AI Baseline API key, then review and approve access to the collection.
   Enter the key on that page, rather than in ChatGPT's OAuth client fields.

7. Start a new conversation, type **@**, and select **AI Baseline S\&P 500**.

## Try your first question

With the connection selected, send:

```text theme={null}
Use AI Baseline S&P 500 to tell me which filings and date ranges are available.
```

ChatGPT should call the collection overview tool and describe the returned
coverage. A successful tool call confirms that authorization worked.

Then ask a question that needs filing evidence:

```text theme={null}
Use AI Baseline S&P 500 to explain the supply chain risks Apple disclosed in its
10-K filings. Cite the supporting filing evidence and identify the filing years.
```

ChatGPT should retrieve evidence and use its source references in the answer.
The [citation guide](/guides/citations) explains how source links work and when
they expire.

## If something goes wrong

| Problem | What to do |
| - | - |
| **Add custom MCP server** is unavailable | Check your account's custom MCP access and workspace permissions with your administrator. |
| Creation or tool discovery fails | Check that the server URL matches the one above exactly and that OAuth is selected. |
| AI Baseline rejects your key or access | Check that the key is valid and grants access to this collection with the person who supplied it. |
| ChatGPT does not use the connection | Confirm the plugin is installed, select it with **@** in a new conversation, and explicitly ask ChatGPT to use it. |
| The search returns no supporting evidence | Check the collection's coverage and narrow the question. Connection success does not guarantee evidence for every question. |


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