#Fast Mode

Fast Mode requests the upstream high-priority lane: shorter queues, faster first tokens. It can be forced directly on an API key — no client changes needed — which is especially useful for clients without a Fast switch of their own.

#Setting it

1. Open the API Keys page.
2. Create a new key or edit an existing one.
3. Set the Fast Mode policy dropdown and save.

SCREENSHOT

#The three policies

Force off removes only the Fast flag; other priority parameters set by the client are untouched.

Below the policy sits a fallback on unavailability switch: when the high-priority lane is unavailable, requests fall back to the regular lane (billed at regular prices) instead of failing. Recommended for reliability-first automation.

#Scope and timing

• Applies to all requests on the key, regardless of client or interface;
• Changes take effect immediately — even long-lived connections pick up the new policy on the next turn, no reconnect.

#When force-on does not apply

These cases are silently skipped (no error; sent as regular):

• The upstream platform or credential type behind this request has no priority lane;
• The model itself does not support the priority lane;
• A platform-wide Fast policy set by the administrator overrides per-key settings.

To confirm whether it took effect, check whether the per-request charge on the usage page is in the 2× bracket.

#Related

• Create an API Key — key creation flow
• Billing — billing units and multipliers
• Codex guide — a common Fast use case