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Connect ChatGPT

Connect ChatGPT

ChatGPT has two different setup paths:

  • Hosted connector: use this for ChatGPT web at chatgpt.com when it asks for a remote HTTPS connector URL.
  • Local MCP surface: use this only when your ChatGPT client explicitly supports launching a local MCP server by stdio or connecting to loopback HTTP.

Hosted connector for ChatGPT web

Use hosted mode for ChatGPT’s custom connector/app flow. ChatGPT connects from OpenAI’s infrastructure, so it cannot reach http://127.0.0.1:8765/mcp on your laptop.

  1. In ChatGPT, open your profile menu and go to Settings > Apps & Connectors.

  2. Open Advanced settings at the bottom of the page and enable Developer mode if your account or workspace allows it.

  3. Go to Settings > Connectors > Create.

  4. Fill in the connector metadata:

    FieldValue
    Connector nameicuvisor
    DescriptionConnects ChatGPT to my intervals.icu training data through hosted icuvisor. Use for athlete profile, fitness, wellness, activities, events, training plans, workouts, and safe write workflows. Do not invent unavailable data.
    Connector URLhttps://connect.icuvisor.app/mcp

  5. Click Create.

  6. Complete the hosted icuvisor authorization flow, choose hosted preferences, continue to Intervals.icu, and approve the requested OAuth scopes. Choose core for normal ChatGPT use; use compact only if a smaller/local-compatible ChatGPT surface struggles with the tool catalog, or full for expert workflows that need every tool.

  7. Start a new ChatGPT conversation, click +, choose More, and add the icuvisor connector to the chat.

Verify with:

Use icuvisor to tell me my current FTP and timezone. Do not estimate.

Hosted mode uses Intervals.icu OAuth. Do not paste an Intervals API key into ChatGPT, the connector metadata, or chat.

Provider reference: OpenAI: Connect from ChatGPT.

Local MCP surfaces

Use this section only when the ChatGPT surface you are using explicitly supports local MCP servers. ChatGPT web custom connectors should use the hosted flow above.

Before you start

  • Install icuvisor and run setup.
  • Confirm the binary starts with icuvisor version.
  • Know your non-secret athlete ID and timezone.

Stdio configuration shape

Use the same stdio server definition as the Claude clients when ChatGPT asks for a local MCP server command:

macOS:

{
  "mcpServers": {
    "icuvisor": {
      "command": "/Applications/icuvisor.app/Contents/MacOS/icuvisor",
      "env": {
        "INTERVALS_ICU_ATHLETE_ID": "i12345",
        "ICUVISOR_TIMEZONE": "America/Sao_Paulo",
        "ICUVISOR_TRANSPORT": "stdio",
        "ICUVISOR_TOOLSET": "core"
      }
    }
  }
}

Windows:

{
  "mcpServers": {
    "icuvisor": {
      "command": "C:\\Users\\<you>\\AppData\\Local\\Programs\\icuvisor\\icuvisor.exe",
      "env": {
        "INTERVALS_ICU_ATHLETE_ID": "i12345",
        "ICUVISOR_TIMEZONE": "Europe/Brussels",
        "ICUVISOR_TRANSPORT": "stdio",
        "ICUVISOR_TOOLSET": "core"
      }
    }
  }
}

If your ChatGPT MCP surface expects a single server object rather than a full mcpServers map, use the icuvisor object from the example as that server definition. ICUVISOR_TOOLSET=core is the recommended default for ChatGPT; switch to compact for reduced-catalog compatibility only after starting a fresh conversation.

HTTP alternative

If your ChatGPT MCP surface expects an HTTP URL, start icuvisor with Streamable HTTP on loopback:

macOS:

ICUVISOR_TRANSPORT=http /Applications/icuvisor.app/Contents/MacOS/icuvisor

Windows PowerShell:

$env:ICUVISOR_TRANSPORT = "http"
& "$env:LOCALAPPDATA\Programs\icuvisor\icuvisor.exe"

Then point the client at:

http://127.0.0.1:8765/mcp

Do not bind icuvisor to a LAN address unless you intentionally want other machines to reach the unauthenticated local MCP server. The HTTP transport guide covers the security tradeoff in more detail.

If a ChatGPT UI asks only for a remote HTTPS connector URL, use the hosted connector instead. Do not tunnel the local server with cloudflared, ngrok, or a similar public tunnel; that would expose an unauthenticated MCP endpoint using the intervals.icu credentials configured for the local process.

Verify

Start a fresh ChatGPT conversation after saving the MCP configuration, then ask a simple profile question such as What's my FTP? The expected tool call is get_athlete_profile. After that, try What can I ask icuvisor? for concrete starter prompts. If ChatGPT keeps using old tool names, old schemas, or stale timezone/zone assumptions, follow the stale conversation troubleshooting guide.

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