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

> ## Agent Instructions
> If you are an agent buying services: start with these steps. Every page has a .md version.
> 1. Install the Catalog MCP (live server https://mcp.live.nevermined.app/mcp, sandbox server https://mcp.sandbox.nevermined.app/mcp; rehearse on sandbox with a sandbox API key before live, as keys work only in their own environment; Claude Code and Cursor commands, Codex config.toml entry): https://nevermined.ai/docs/products/catalog/mcp.md
> 2. Get an API key: https://nevermined.ai/docs/agents-guide/get-api-key.md
> 3. Enroll a card and create a delegation (a payment method plus a spend mandate: an amount, an expiry and a number of purchases): https://nevermined.ai/docs/agents-guide/enroll-card.md
> 4. Buy and call a paid agent over x402: https://nevermined.ai/docs/getting-started/ai-agent-purchase.md
> SDK quickstart: https://nevermined.ai/docs/integrate/quickstart/typescript.md. Pricing: https://nevermined.ai/pricing/

# Connect the Catalog from ChatGPT

> Connect the Nevermined Catalog to ChatGPT in minutes — add one MCP app, approve one spending cap, and ChatGPT pays for services as it works. No API key.

ChatGPT can browse the [Nevermined Catalog](/docs/products/catalog/overview) and pay for services as it works, without you handing over an API key. You add one MCP app, approve a single spending cap, and ChatGPT does the rest. This is the per-host walkthrough; for the concept and the other assistants, see [Using the Catalog from your web assistant](/docs/products/catalog/from-your-web-assistant).

<Note>
  This covers the **manual** connection — adding the Catalog as a custom MCP app in Developer mode, which works today. A one-click listing in ChatGPT's connector directory is still in progress — see [From the ChatGPT directory](#from-the-chatgpt-directory).
</Note>

## See it in action

<Frame caption="Connect the Catalog from ChatGPT.">
  <iframe src="https://www.youtube.com/embed/e_-bQlLdRdg" title="Connect the Catalog from ChatGPT" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowFullScreen style={{ width: "100%", aspectRatio: "16 / 9", borderRadius: "0.5rem", border: 0, display: "block" }} />
</Frame>

## Before you connect

<Steps>
  <Step title="A Nevermined account">
    Free, at [nevermined.app](https://nevermined.app). You never share an API key with ChatGPT — the consent cap *is* the credential.
  </Step>

  <Step title="A paid ChatGPT plan">
    Developer mode, where custom MCP apps live, needs a paid plan (Plus or above).
  </Step>

  <Step title="A funded wallet">
    A paid call draws on a **spending cap** you approve during connect — a [commerce grant](/docs/mcp/catalog-mcp/overview#auth-&-transport): a capped, revocable budget funded from your own wallet, not a key. Fund that wallet first with the asset the service settles in — see [Fund your wallet](/docs/products/catalog/router/quickstart#3-fund-your-wallet). You approve the cap itself in [Approve the spending cap](#approve-the-spending-cap).
  </Step>
</Steps>

<Note>
  Start on **sandbox**, where you use testnet funds and nothing costs real money, before you point ChatGPT at **live**.
</Note>

## Add the Catalog to ChatGPT

<Steps>
  <Step title="Turn on Developer mode">
    **Settings → Security and login → Developer mode.** *Plugins* then appears in the sidebar.
  </Step>

  <Step title="Create an MCP app">
    **Plugins → ＋ → Create app → Create MCP app.** (The ＋ menu's *Create plugin* builds a plugin from scratch — not what you want.)
  </Step>

  <Step title="Fill in the dialog">
    * **Name** — read the warning below first; you only get one shot at it.

    * **Connection** — leave it on **Server URL** and paste the URL for your environment:

      | Environment | Server URL |
      | - | - |
      | **Sandbox** — the right place for a first run | `https://mcp.sandbox.nevermined.app/mcp` |
      | **Live** — real merchants, real money | `https://mcp.live.nevermined.app/mcp` |

    * **Authentication** — **OAuth**, with the client ID and secret **empty**. ChatGPT discovers the OAuth settings from the server itself; leave **Advanced OAuth settings** closed.

    * Tick **I understand and want to continue** under the *"Custom MCP servers introduce risk"* notice.
  </Step>
</Steps>

<Warning>
  **Choose the name carefully — a ChatGPT plugin cannot be deleted or renamed.** Names are unique per account, so a name you have used is taken for good, and uninstalling does not free it.
</Warning>

## Approve the spending cap

ChatGPT runs Nevermined's consent **at creation** — immediately, before any tool call. It is the one place a human is required.

<Steps>
  <Step title="Trigger the consent">
    When you create the MCP app, ChatGPT shows *Add Nevermined … to ChatGPT?* and opens the consent page.
  </Step>

  <Step title="Check who and where">
    The page shows the **Sandbox / Live** badge and that **chatgpt.com** is asking. On **live**, the cap is real money.
  </Step>

  <Step title="Set the cap and validity">
    Set the **spending cap** (USDC or EURC) and how long the grant is **valid for**, then **Grant access**. The plugin shows as connected.
  </Step>
</Steps>

That approval is a **commerce grant**: it spends only from the budget you just approved, only through the [Router](/docs/products/catalog/router/overview), and you can revoke it any time. Nevermined's routing fee comes out of the same cap, and the grant can also read your payment history and wallet balance — [the cap bounds what it can spend, not what it can see](/docs/mcp/catalog-mcp/overview#what-the-consent-page-asks).

## Make your first paid call

Ask for something only live data can answer, and name the connector so ChatGPT reaches for it rather than answering from memory.

<Steps>
  <Step title="Browse for free">
    In a new chat the plugin is available automatically. Ask *"list the Nevermined catalog categories"* — a free call, no sign-in.
  </Step>

  <Step title="Ask it to buy">
    *"Buy the service with slug `<slug>` through the Nevermined connector and show me the response."* Each paid call first asks *Allow ChatGPT to use Nevermined …?* — **Allow** (once, or always), and it returns the merchant's response.
  </Step>
</Steps>

<Tip>
  If ChatGPT answers without paying, it answered from its own knowledge — name the connector and ask for live data. Confirm the connection by asking for the Catalog categories, which is a free call that either works or doesn't. More on phrasing: [Catalog MCP tips](/docs/mcp/catalog-mcp/overview#connect-from-your-assistant).
</Tip>

## Disconnect

* **Revoke the budget (Nevermined side).** Open [Connections](https://nevermined.app/connections) and disconnect ChatGPT. The credential stops working on its next call; discovery still works. On the next paid call ChatGPT shows a **Reconnect Nevermined** card (its wording says the connection "expired" even when you revoked it).
* **Remove the connector (ChatGPT side).** Uninstall the plugin from **Plugins**. Note the plugin **cannot be deleted or renamed**, and uninstalling does not free its name.

To spend again — after you disconnect, or after a cap is used up — re-run the connect step and approve a **new** cap. A budget is never widened or extended in place.

## From the ChatGPT directory

<Note>
  A one-click listing in ChatGPT's app directory — so you can add the Catalog without Developer mode — is coming. Until then, use the manual path above.
</Note>

## Next

<CardGroup cols={2}>
  <Card title="Using the Catalog from your web assistant" icon="comments" href="/docs/products/catalog/from-your-web-assistant">
    The concept and the other assistants.
  </Card>

  <Card title="Catalog MCP — full reference" icon="plug" href="/docs/mcp/catalog-mcp/overview#connect-from-your-assistant">
    Every click path, the consent details, and every refusal code.
  </Card>
</CardGroup>


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