Codex

Overview

Codex is OpenAI's coding agent, powered by ChatGPT. ZoomInfo ships as a Codex plugin, so a single install gives Codex the hosted ZoomInfo MCP server and our GTM skills at once. If your Codex build doesn't expose plugins yet, add the MCP server by hand through the Custom MCP form. Both connect to the same endpoint and authenticate over OAuth.

Setup

Next - run your first session. Once ZoomInfo is connected, paste this into a new Codex session. It orients from your GTM context and only runs after you approve:

(Use the ZoomInfo MCP tools if available; otherwise use the GTM CLI.)

I just connected ZoomInfo. Help me get real value from my ZoomInfo credits today - I want to spend them on the most valuable first thing to do. Don't run anything I haven't picked yet.

1. Call get_gtm_context - it's free (no credits). Use whatever it returns, plus my company name and email domain, to work out what we sell and who we target. Don't ask me, just figure it out.

2. Say it back in one line: "You're <Company>, selling <offering> to <ICP>." Check I agree. Once I confirm, save it by calling update_gtm_context so my GTM context is set for next time. If I'm not an admin, the save will fail - that's fine, just continue.

3. Offer me 3 concrete first actions grounded in my context, using our named ZoomInfo skills:
   • Run **Meeting Prep** for an upcoming call - decision-ready brief with talking points
   • Run **Account Research** on a target company - firmographics, signals, buying committee
   • Run **Build List** to find companies matching our ICP - ranked, exportable

If none of those fit, I can also ask for any of our other named skills. Let me pick one, or tell you my own goal.

4. Only once I've chosen: tell me which ZoomInfo tools you'll run and roughly how many credits it'll cost. Go ahead - that's what they're for. Just tell me the cost before running so I stay in control.

Keep it fast. A quick, real win - not a tour and not a list I didn't ask for.

What the Plugin Adds

The plugin bundles the hosted MCP server at https://mcp.zoominfo.com/mcp plus a set of GTM skills, prewritten workflows that chain the underlying tools into finished output: account briefs, target lists, buying-committee maps, and lead scores. To run one explicitly, type @ in the Codex prompt and pick the skill. Otherwise describe the outcome and Codex selects the skill that fits.

For the full skill list and a deeper walkthrough, see the Codex setup guide.

Prefer the Manual Route? Custom MCP

If your Codex build doesn't expose plugins, or you want the server without the bundled skills, add it through the Custom MCP form:

Troubleshooting

You don't see ZoomInfo in the Plugin Directory: the listing may not have reached your directory search yet. Fall back to the Custom MCP route above.

Codex doesn't show a Custom MCP option: your Codex plan or workspace may not have Custom MCP enabled. Check with your OpenAI admin or workspace owner.

Authentication fails on sign-in: confirm you're using your personal ZoomInfo credentials, not a shared or admin-only account.

Codex doesn't see any ZoomInfo tools: for the plugin, confirm it shows as installed and enabled in /plugins. For Custom MCP, confirm the entry is listed and the URL is exactly https://mcp.zoominfo.com/mcp.

Credit errors on enrichment or research calls: MCP requires bulk data credits. Confirm with your ZoomInfo admin that your account has bulk credits enabled, not recurring monthly credits.

What's Next

For the full walkthrough including every GTM skill, see How to Add ZoomInfo to Codex. For the same setup in Anthropic's CLI, see Claude Code. For the full tool reference, see the MCP Tools documentation.