ChatGPT

Create Valency once on the web for ChatGPT in the browser, desktop app, and mobile app. Codex CLI needs a separate connection.

ChatGPT setup steps

Already connected? Click + beside the message box and look for Valency. If it is there, select it and skip setup.

1. Add Valency to ChatGPT

   On mobile: Tapping a ChatGPT link may open the app, where the setup form isn't available. Paste the copied address into the address bar of a new browser tab instead. After setup, Valency works in the app too.

   Open ChatGPT Plugins ↗, click Add → Add custom MCP server, then fill in the form with:

   Copy the ChatGPT Plugins address and paste it into your browser's address bar. Click Add → Add custom MCP server, then fill in the form with: Copy web address

   Name	Valency	Copy
   Description	Infrastructure for Agentic Science	Copy
   Connection (Server URL)	https://mcp.valency.io/	Copy

   Leave Authentication on OAuth, check I understand and want to continue, and click Create as a plugin.

2. Sign in with Valency

   Click Sign in with Valency, continue through Valency's consent screen, and sign in with Google, GitHub, or Microsoft.

3. Verify the connection

   Return to your ChatGPT conversation, refresh the browser page if needed, click + beside the message box, and select Valency. Then ask:

   Use Valency to list the sources it can search. Copy

   If Valency has not appeared in the desktop or mobile app yet, fully close and reopen the app.

Can't find Add custom MCP server?

In the desktop app, the alternate route is Customize → Plugins → Add → Add custom MCP server. If neither route shows the MCP server form, contact support@valency.io with the screen you see.

Use it in the mobile app

After creating Valency in your mobile browser, start a new ChatGPT conversation in the mobile app and ask it to use Valency to list the sources it can search. If Valency is not available yet, fully close and reopen the app, then try again. Complete setup in your browser; the mobile app cannot create a custom MCP app.

Use it in the desktop app

Chat and Work Cloud

The MCP app follows your ChatGPT account. In a desktop Chat or Work conversation, click + beside the message box, choose Plugins, and select Valency — Infrastructure for Agentic Science. Ask ChatGPT to use Valency to list its sources. A returned source list verifies that the tools work in that conversation.

If Valency is missing from the + menu, check Customize → Plugins → Personal. If it is connected there, click ... → Try now if available to open a chat with Valency selected. Otherwise fully quit and reopen the desktop app, then check the + menu again. Do not create a duplicate app while it is present in Plugins settings.

Work Local

In Work → Local, the same browser-created app is available; no marketplace plugin is needed. If Valency is connected but absent from the conversation's + menu, check Customize → Plugins → Personal. If available, click Valency's ... → Try now to open a Work conversation with it selected. Otherwise fully quit and reopen the desktop app, then try again. Do not create a duplicate connection while it is present in Plugins settings.

Codex mode

In Codex mode inside the desktop app, the same account connection is available. If it does not appear yet, fully quit and reopen the app, start a Codex conversation, and ask Codex to call Valency's list_sources tool. Codex CLI is a separate terminal product with its own MCP setup.

If the browser form is unavailable

The desktop app has an alternate route to create the same account MCP app. In ChatGPT mode, open Customize → Plugins → Add → Add custom MCP server. Enter the name, description, and server URL shown in step 1 above. No API token, client ID, or secret is needed. Leave Authentication on OAuth, check I understand and want to continue, and click Create as a plugin, then Continue to Valency and complete browser sign-in.

ChatGPT returns to the plugin list, but Valency may take a few seconds to appear under Installed. Wait for the green confirmation toast. Once it appears, return to your conversation, click + → Plugins, and select Valency — Infrastructure for Agentic Science. If it is connected under Customize → Plugins → Personal but still absent from the chat picker, use ... → Try now if available. Otherwise fully quit and reopen the app and start another conversation. Do not create a second MCP app while the connection is updating.

Troubleshooting

Valency is missing from the browser chat's + menu? Refresh a chat that was open before you created the app. Search the + menu for Valency; some layouts put it under Plugins or More. If it remains missing, select it in a new chat. Do not create a duplicate app.

The app is selected but its tools are unavailable? Check that Sign in with Valency was completed after Create as a plugin. Try a new conversation with Valency selected and ask for its source list again.

Desktop controls are missing? Update to the current ChatGPT desktop app. The older Classic app does not have this plugin flow. If two Valency entries appear, choose Valency — Infrastructure for Agentic Science for the ChatGPT MCP app.

Authorization fails or times out? Retry sign-in and check which Valency account you used. Your Valency email does not have to match your ChatGPT email. A Valency account is created automatically on first sign-in.

If neither the browser nor desktop route shows Add custom MCP server, custom MCP app creation may be unavailable in this account or workspace. Contact support@valency.io with the screen you see. See Troubleshooting for other connection issues.