OpenAI Agents API changelog

Every change to OpenAI Agents API that Modelpeers has recorded, newest first, each with the source it came from. The record starts Sep 10, 2026.

All (3)Releases (2)Prices/limits (1)

October 2026

OpenAI Agents API

API at OpenAI

Now available2w

Ultrafast mode added to the Agents API

The Agents API now supports Ultrafast mode by setting agent.service_tier to ultrafast with a supported model, to reduce the time between generated tokens.

OpenAI Agents API

API at OpenAI

Price change3w

Agents API sandbox compute billed only during active turns

OpenAI-hosted sandbox compute in the Agents API is now billed only during active turns, not idle time between turns.

Who is affected:: Agents API customers using OpenAI-hosted sandboxes.
What to do:: No action needed. Costs drop automatically.

September 2026

OpenAI Agents API

API at OpenAI

New releaseSep 10, 2026

Agents API released in public beta

OpenAI released the Agents API in public beta: agents run on a managed Codex harness with durable sessions, in OpenAI-hosted or self-hosted sandboxes.

3 incidents are listed on the OpenAI Agents API page. Get this changelog in a feed reader with the RSS feed.