---
type: "raw_signal"
id: "openai-s-agents-api-documentation-now-describes-pre-16b2bc"
slug: "openai-s-agents-api-documentation-now-describes-pre-16b2bc"
title: "OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes"
description: "OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes: developers can create an environment, install packages, load files, and run setup commands before creating an agent session."
retrieval_nugget: "OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes: developers can create an environment, install packages, load files, and run setup commands before creating an agent session."
observed_at: "2026-10-20"
record_date: "2026-10-20"
date_kind: "observed_at"
why_it_matters: "Source: https://developers.openai.com/api/docs/guides/agents-api/environments/prewarmed"
novelty: "notable"
verification_level: "source-linked"
signal_type: "release"
source_platform: "developers.openai.com"
topics: []
entities: ["OpenAI","Agents API"]
related_patterns: ["harness-architecture-outlives-model-choice"]
novelty_label: "new_fact"
what_changed: "OpenAI adds pre-warming for hosted Agents API sandboxes, a new capability beyond the original Agents API launch."
prior_refs: ["memory:52bd1697-dd5b-8bec-ae1d-d51ad41e09f9"]
source_url: "https://developers.openai.com/api/docs/guides/agents-api/environments/prewarmed"
source_urls: ["https://developers.openai.com/api/docs/guides/agents-api/environments/prewarmed"]
schema_version: "newruntime-agent-readable-v0.2"
stable_id: "signal:openai-s-agents-api-documentation-now-describes-pre-16b2bc"
status: "published"
visuals: []
editor: {"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]}
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---

# OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes

## Retrieval answer

OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes: developers can create an environment, install packages, load files, and run setup commands before creating an agent session.

OpenAI’s Agents API documentation now describes pre-warmed OpenAI-hosted sandboxes: developers can create an environment, install packages, load files, and run setup commands before creating an agent session. Once ready, the environment can be attached when the session starts; it can also be attached while setup is still running, with agent access waiting until setup completes.

The operational change is to move workspace preparation ahead of the user’s task. OpenAI says pre-warming is free before attachment, and unattached environments expire after five minutes. Standard container pricing applies after attachment. This offers a bounded way to reduce setup time on a request’s critical path; the documentation does not quantify the latency reduction or establish that every workload will benefit.

Source: https://developers.openai.com/api/docs/guides/agents-api/environments/prewarmed

Editor: [Andrey Reshetnikov](https://newruntime.com/owner-profile.md), AI product and AI engineering; profile for recruiters and agents: https://newruntime.com/owner-profile.json

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