Can it handle multiple Gmail accounts?
Yes. Approve each Gmail account you want available, then identify the work or personal inbox in your prompt.
Finally connect multiple Gmail accounts and Slack workspaces to Claude, ChatGPT, or Codex.
One simple setup keeps every inbox and workspace connected without constantly logging out, switching accounts, or losing the thread.
Want the whole dashboard?Build a custom Life OS prompt from your accounts, work, family, and interests. →
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Jump To The Steps
AI result
Prompt
Search personal-gmail, work-gmail, agency-slack, and client-a-slack for the renewal thread. Label every source.
Renewal timing from Mara
Inbox match from Tuesday morning
work-gmail
Thread in #partner-renewals
Two replies mention the same date
client-a-slack
Old invoice email found
Useful context, not the newest source
personal-gmail
Clean answer
The renewal appears to be waiting on finance approval. Most recent source is client-a-slack, then work-gmail.
Safety default
Read and summarize first. Ask before posting or sending anything.
How do you connect multiple Gmail accounts and Slack workspaces to an AI?
Multi Connector is a free setup guide for connecting more than one Gmail account and Slack workspace to Claude, ChatGPT, or Codex through Composio. Create one free Composio account, add its connector to the AI app you use, and sign in to every Gmail account or Slack workspace you choose to approve. Then, when you ask your AI to find something, say “Use Composio” and name the inbox or workspace you want it to search. This keeps the accounts separate while making it easier to find the latest thread, compare context, or prepare for a meeting without logging out and back in. It does not bypass company permissions or turn your accounts into a shared inbox.
Can it handle multiple Slack workspaces?
Yes. Connect every workspace you are allowed to authorize, including team and client workspaces.
Who controls access?
You do. Every connection uses your own login and can be removed from Composio or your AI app settings.
A practical fix for annoying one-account limits.
1
Create your free Composio account.
Start here so Composio has somewhere to manage the accounts you approve. You will use this same account whether you connect it to Claude, ChatGPT, or Codex.
https://login.composio.dev/sign-up
Open
2
Connect Composio to the AI you use.
Choose your app below. The setup is slightly different in each one.
In Claude
Open Settings, go to Connectors, choose Add custom connector, and paste this URL. Name it "Multi Connector," then complete the Composio sign-in.
https://connect.composio.dev/mcp
In ChatGPT on the web
Open Settings > Apps > Advanced settings and turn on Developer Mode. Choose Create app, paste the URL below, select OAuth, scan the tools, approve the Composio sign-in, and create the app. In a new chat, select Composio from the tools menu before using it.
https://connect.composio.dev/mcp
Let Codex handle the setup
Paste this into a Codex task. Codex will add the MCP server and open the Composio authorization flow. You will still approve the OAuth screen yourself. When it is finished, start a new task so the Composio tools load.
Add the Composio MCP server globally using https://connect.composio.dev/mcp. Walk me through the OAuth login, then verify that Composio is enabled and authenticated. Do not connect Gmail or Slack yet.
3
Ask it to connect Gmail and Slack.
Your AI should open browser approval links through Composio. Sign in with the account you want to connect, review the permissions, and approve only what you understand.
Use Composio to connect my Gmail and Slack accounts. Start with read/search use cases only.
4
Repeat the connection flow for every extra account.
If it says Gmail and Slack are already connected, that only means one of each is active. Ask for a fresh connection link for the next Gmail account or the next Slack workspace.
Using only Composio, help me add another Gmail account and another Slack workspace. Generate fresh OAuth connection links for each one. Do not reuse the Gmail or Slack connection that is already active.
5
Add friendly labels only where the default names are unclear.
Most Gmail addresses and Slack workspace names are already useful. Add simple labels only when you want a more natural way to refer to them, like personal email, main work email, or client Slack.
Using only Composio, list my connected Gmail accounts and Slack workspaces. Keep the existing email addresses and workspace names, but help me add friendly labels for any that are ambiguous, like personal email or client Slack.
When you use it, tell your AI to use Composio.
Composio is the connector that can see the accounts you approved. Try: "Use Composio to search my work Gmail" or "Use Composio to access my personal Gmail."
Boom. You should be good to go!
Copy-paste prompts that make multiple accounts useful.
Find one topic across everything
Use Composio to search all connected Gmail accounts and Slack workspaces for “[topic/person/company]”. Return the most relevant results grouped by source. For each result, show the email address or Slack workspace, date, sender, and why it matters.
Morning catch-up
Use Composio to check my connected business Gmail accounts and Slack workspaces from the last 24 hours. Summarize only items that likely need my attention. Group by: urgent, waiting on me, useful context, and can ignore.
Thread recovery before a call
I have a call about [client/project] in 20 minutes. Use Composio to search connected Gmail and Slack sources for recent context. Give me a briefing with: latest decision, unresolved questions, people involved, and links or identifiers for the source messages.
Find the source of truth
Use Composio to search across connected Gmail and Slack for [topic]. Tell me which source appears most current and authoritative. Separate confirmed facts from guesses. If Gmail and Slack disagree, show the conflict clearly.
Personal versus work split
Use Composio to search my personal Gmail and business Gmail separately for “[topic]”. Keep the results in two sections. Do not mix personal and business context unless the same person or thread appears in both.
Draft, do not send
Use Composio to review the latest Gmail and Slack context about [topic], then draft a reply I could send from [email account]. Do not send it. Include the source messages you used so I can verify the draft.
Security tidbits
Good first uses
- Search multiple Gmail accounts for a thread, receipt, or contact.
- Summarize Slack activity across workspaces before a meeting.
- Compare Gmail and Slack context for the same project.
- Find the newest source and show which account it came from.
Keep guarded
- Do not allow write actions until you are comfortable with the setup.
- Do not click Allow always for tools you do not recognize.
- Do not connect accounts you would be nervous to expose to any third-party connector.
- Disconnect accounts from Composio or your AI app's settings if anything feels wrong.
Is something stuck?
It only searches one account.
Ask it to list the connected Gmail and Slack accounts it can see through Composio. If the second account is missing, connect it again and give it a clear alias.
The OAuth link expired.
Ask your AI to retry the connection. Composio approval links can expire, so a fresh link is usually enough.
A Slack workspace needs admin approval.
Some Slack workspaces require an owner or admin to approve app installs. That is a workspace policy, not an AI-app issue.
I want to remove access.
Disconnect Composio in your AI app's settings and remove the connected account from Composio. You can also revoke Google and Slack access from their own security settings.
Does the safety prompt apply everywhere?
No. If you paste it into one chat, it guides that chat. For persistence, add it to that app's project or profile instructions when available. For real enforcement, keep risky connector tools set to needs approval or disabled.
Send to a friend.
Know someone juggling multiple Gmail inboxes or Slack workspaces? Send them this setup guide so their AI can search across the accounts they actually use.