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Forge

Sign in with ChatGPT

Forge does not ship its own LLM API key. The agent runs against your ChatGPT plan via OAuth. That has three consequences worth knowing:

  • You pay for inference. Your existing ChatGPT subscription covers it.
  • Forge never sees the raw OAuth token. It lives in Windows Credential Manager and is read by the bundled Codex sidecar at session start.
  • Sign-out is a single click. Revoking from chatgpt.com revokes Forge automatically.

The flow

Section titled “The flow”
  1. Click Sign in with ChatGPT on the welcome screen, or Settings → Account → Sign in.
  2. Your default browser opens to ChatGPT’s auth page.
  3. Authorize Forge.
  4. The browser bounces back to a localhost: callback that Forge listens on.
  5. The token is stored in your OS keyring. Forge re-reads it on every launch.

What model gets picked

Section titled “What model gets picked”

After you authorize, Forge picks the latest GPT-5 reasoning model your plan exposes. You can override the default in Settings → Account → Default model, or per-session in the model dropdown next to the prompt input.

For image generation in chat, Forge uses gpt-image-2 by default. Override in Settings → Account → Image model.

Sign out

Section titled “Sign out”

Settings → Account → Sign out clears the keyring entry. The next session prompts for re-auth. Forge cannot run agent turns without a connected account.

Next

Section titled “Next”