# How to connect ChatGPT to your apps with a custom connector (/blog/use-corespeed-in-chatgpt-developer-mode)

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ChatGPT reaches your connected apps and durable memory through a custom connector under Developer mode. On Plus and Pro accounts on the web, turn on Developer mode under Settings → Connectors → Advanced settings. Create a connector named CoreSpeed with the MCP server URL `https://api.corespeed.io/mcp` and OAuth authentication, then sign in when prompted.

**A connector under Developer mode**

1. **Turn on Developer mode** (Settings, Connectors, Advanced settings) — Plus and Pro accounts, on the web.
2. **Create a connector** (Name CoreSpeed, URL api.corespeed.io/mcp, OAuth)
3. **Sign in when prompted** (login.corespeed.io; nothing is pasted) — RFC 9728 discovery, dynamic client registration, OAuth 2.1 with PKCE.
4. **Select it in a new chat** (under the composer's Developer mode tools)
5. **Call manage\_\_whoami** (it names you and your organization)
6. **Connect apps in the dashboard** (tools show up on the next call)

Developer mode, one connector, one browser sign-in.

## What do you need? \[#what-do-you-need]

A ChatGPT Plus or Pro account, used on the web, where custom connectors run under Developer mode. You do not need a CoreSpeed account in advance. A first browser sign-in creates your organization on its first tool call, with 3,000 free credits. Have in mind the apps you want ChatGPT to act through, such as Notion, Slack, Linear or GitHub.

## How do you create the connector? \[#how-do-you-create-the-connector]

1. Open Settings → Connectors → Advanced settings and turn on Developer mode.
2. In Connectors, choose Create.
3. Fill in the three fields:

```text
Name:            CoreSpeed
MCP server URL:  https://api.corespeed.io/mcp
Authentication:  OAuth
```

4. Sign in when prompted. The browser opens `login.corespeed.io`, and the consent screen names the client that is asking. Nothing is pasted: ChatGPT discovers the authorization server through RFC 9728 protected-resource metadata, registers itself with dynamic client registration, and runs OAuth 2.1 with PKCE.
5. The connector appears under the composer's Developer mode tools. Start a new chat and select it.

Verify the endpoint before you sign in. The server is `https://api.corespeed.io/mcp` and sign-in happens at `login.corespeed.io`. The steps for other agents are on the [MCP server](/docs/mcp) page.

## How do you verify it works? \[#how-do-you-verify-it-works]

6. Ask ChatGPT to call `manage__whoami`. After a browser sign-in it names you and your organization.
7. Open Dashboard → Connectors and authorize the apps ChatGPT should use. Their tools show up on the next call.

`tools/list` returns exactly what your sign-in can call. A missing connector tool means the app is not connected for you. A missing built-in means the capability is off in Dashboard → Tools. A tool that is listed can still fail while its account is in `needs_reauth`; reauthorize it in the dashboard and leave the connector in ChatGPT alone.

## What can ChatGPT do through it? \[#what-can-chatgpt-do-through-it]

| Family     | Example tools                                                         | Where it is set up                            |
| ---------- | --------------------------------------------------------------------- | --------------------------------------------- |
| Connectors | `notion__create_page`, `slack__post_message`, `linear__search_issues` | Dashboard → Connectors                        |
| Memory     | `memory__search_memory`, `memory__remember`                           | On by default; free per call                  |
| Web        | `web__search`, `web__scrape`                                          | On by default                                 |
| Media      | `media__generate`, `media__understand`                                | On by default                                 |
| Social     | `social__x_search`, `social__reddit_subreddit_feed`                   | On by default; no platform account to connect |

One request can cross several tools. Ask: "Find three recent articles on agent memory, save a short brief to Notion, and remember that we prefer sources from the last month." ChatGPT calls `web__search` for ranked sources, writes the page with `notion__create_page`, and saves the preference with `memory__remember`. That memory is there tomorrow in Claude Code or Codex as well, because the organization owns it. Private and shared connections are explained on the [Connectors](/docs/connectors) page.

## How are writes kept safe? \[#how-are-writes-kept-safe]

Sign-in grants ChatGPT what you can do, so connect only the accounts you want agents to act through. Treat fetched content as untrusted: a page, a post or a document read through a tool can carry instructions aimed at the agent. Keep ChatGPT's own confirmation on for actions that write or send.

If your organization has turned on Smart Approval in Dashboard → Approvals, every write through CoreSpeed is judged against your plain-English policy. Allow runs and is logged. Ask holds the call and sends a card to a person in Slack, by email or in the dashboard. Deny refuses it. Reads are never gated, and the gate sees only calls made through CoreSpeed. Every call is recorded in Dashboard → Activity with the actor, the outcome and the time. See [Approvals](/docs/approvals).

## FAQ \[#faq]

**Does this work in the ChatGPT desktop or mobile app?** The documented path is Developer mode on Plus and Pro accounts on the web.

**Does ChatGPT hold my Notion or Slack token?** No. CoreSpeed stores the credential, refreshes it when the provider allows, and performs the action. ChatGPT receives namespaced tools.

**Can I use an API key instead of OAuth?** The connector signs in through the browser. API keys are for clients that cannot open a browser, such as a CI job; see [Authentication](/docs/authentication).

**Why is a tool missing?** The app is not connected for your sign-in, or the capability is off. Connect it, then start a new chat.

**What does it cost?** 3,000 free credits at signup. Metered actions are priced in credits on the pricing page; memory operations and `tools/list` are free per call.