Add dossaro to ChatGPT

Until dossaro is listed in the ChatGPT app store, add it as a custom MCP app in ChatGPT developer mode. The important part is getting developer mode enabled first, then pasting the exact dossaro MCP endpoint during app creation.

OpenAI documents current availability and setup details in its Help Center article: Developer mode and MCP apps in ChatGPT.

What you need#

• ChatGPT on the web. Custom MCP apps are not set up from mobile.
• A ChatGPT Business, Enterprise or Edu workspace that supports developer mode and custom MCP apps.
• Admin/owner access, or developer-mode access granted by your workspace admin.
• A dossaro account. ChatGPT will send you through dossaro OAuth during setup.

Copy these values#

Use these exact values when ChatGPT asks for the custom app details:

App name: dossaro
MCP server URL: https://mcp.dossaro.com/mcp
Authentication: OAuth

If ChatGPT only asks for the server URL, paste this:

https://mcp.dossaro.com/mcp

Enable developer mode#

Developer mode is controlled by your ChatGPT workspace. If you do not see the settings below, you probably do not have the right workspace role yet.

Business workspaces#

1. Open ChatGPT on the web.
2. Open Settings.
3. Go to Apps.
4. Open Advanced settings.
5. Turn on Developer mode.

Admins and owners can also enable developer mode during app creation:

Workspace settings -> Apps -> Create

On Business plans, each admin or owner turns developer mode on for their own account. The toggle does not automatically enable developer mode for every admin in the workspace.

Enterprise and Edu workspaces#

Workspace admins can grant developer-mode access here:

Workspace Settings -> Permissions & Roles -> Connected Data -> Developer mode / Create custom MCP connectors

After access is granted, the enabled user turns it on here:

Settings -> Apps -> Advanced Settings

Create the custom app#

1. Open ChatGPT on the web.
2. Go to Settings -> Apps.
3. Choose Create.
4. If ChatGPT asks for an app name, enter:

dossaro

1. When ChatGPT asks for the MCP server URL, paste:

https://mcp.dossaro.com/mcp

1. Choose OAuth as the authentication method.
2. Click Scan Tools.
3. Keep the ChatGPT setup tab open while the dossaro authorization window opens.

Authorize dossaro#

1. Sign in to dossaro when the OAuth prompt opens.
2. Approve the ChatGPT connection.
3. Return to the ChatGPT setup flow.
4. Wait until Scan Tools finishes.
5. Click Create.

After creation, ChatGPT should show the app as a draft app. In user settings it may appear under enabled apps with a Dev label.

Use the draft app#

1. Start a new chat.
2. Open the + / tools menu.
3. Select the draft dossaro app.
4. Ask a source-backed company research question, for example:

Find shareholder evidence for Atlas Beteiligungen GmbH.

You can also try invoking the app by name in the prompt if it is enabled for the chat.

See also: Research MCP reference for the tool list, source coverage and jurisdiction limits.

Troubleshooting#

I do not see developer mode#

• Confirm you are using ChatGPT on the web.
• Confirm your workspace is Business, Enterprise or Edu.
• Ask a workspace admin or owner to enable developer mode or grant developer access.
• In Enterprise/Edu workspaces, check both the admin permission path and your own Settings -> Apps -> Advanced Settings toggle.

I do not see Create in Apps settings#

• You may not be an admin/owner or authorized developer.
• Your workspace may not allow custom MCP apps.
• Ask your workspace admin to create the app or grant developer-mode access.

Scan Tools fails#

• Confirm the URL is exactly:

https://mcp.dossaro.com/mcp

• Confirm the authentication method is OAuth.
• Open https://mcp.dossaro.com/mcp in a browser tab only to check reachability; the endpoint is not meant to be used directly by a human.
• Retry Scan Tools after signing in to dossaro in the OAuth prompt.

The OAuth prompt does not return to ChatGPT#

• Keep both the ChatGPT setup tab and the dossaro authorization tab open.
• Complete the dossaro approval step, then return to ChatGPT.
• If the setup flow looks stuck, cancel and create the custom app again.

The app is not visible in a chat#

• Start a new chat after creating the app.
• Open the + / tools menu and check that the draft dossaro app is enabled.
• If an admin published the app for the workspace, check your workspace app access.

Tools changed after setup#

After an app is approved, ChatGPT may use a frozen snapshot of its tools. If dossaro adds or changes tools later, an admin may need to refresh, recreate or republish the custom app depending on the workspace plan and controls.