API Changelog

The chat-latest snapshot now points to the latest model available in ChatGPT for Plus, Pro, Business, and Enterprise users, with the underlying snapshot updated regularly. Production API usage should use the GPT-6 model family; chat-latest is for testing the latest chat improvements.

API usage tiers are simplified from five to three: Build, Launch, and Grow. Organizations automatically upgrade as total credit purchases reach tier minimums.

Released the Decisions API in beta with gpt-6-luna, turning text and images into typed answers 10x faster than the Responses API.

Admins of eligible organizations can now accept the standard Business Associate Agreement and enable HIPAA compliance support directly from Organization settings > General.

Ultrafast mode for GPT-6 Astra is available in the Responses API via service_tier: "ultrafast", reducing the time between generated output tokens. It is subject to rate limits, restricted to global processing and US data residency, and EU and other regional inference residency aren't supported.

Computer use is now available in the Agents API, letting agents complete tasks in an OpenAI-hosted browser, with website access approvals and sign-in handled by the calling application.

GPT-6.1 Sol (gpt-6.1-sol) is available for complex coding and professional work at a lower cost than GPT-6 Astra, priced at $2 input, $0.10 cached input, $2.50 cache write, and $10 output per 1M tokens for prompts up to 272K input tokens. It also supports Multi-agent in beta, letting the model delegate work to subagents in a Responses API request.

An image encoding bug that degraded image understanding in GPT-6 Sol and GPT-6 Luna is fixed, improving results on visual tasks in the API and Codex, including computer use. OpenAI recommends rerunning evaluations and retrying workflows that use image inputs.

GPT-6 Sol and GPT-6 Luna are released as reasoning models that accept text and image inputs and generate text through the Responses and Chat Completions APIs. Standard pricing per 1M tokens for prompts up to 272K input tokens is $2 input, $0.20 cached input, and $10 output for Sol, and $0.10 input, $0.01 cached input, and $0.50 output for Luna.

Administrators can now restrict API key creation at the organization and project levels to service-account keys only, user-owned project keys only, or disable new key creation entirely, with organization restrictions taking precedence over project settings. Existing API keys are unaffected.

Project API keys can now be created with expiration dates, and administrators can enforce a maximum key lifetime at the organization or project level in Platform settings so newly created keys expire within the configured limit.

GPT-Live 1 is now generally available in the API for full-duplex voice conversations that continue while a backend model or agent handles reasoning and tools, using Responses delegation with an OpenAI model or client delegation to a custom backend. Voice sessions cost $0.05 per minute, billed per second, with backend model and tool usage charged separately.

OpenAI released the Agents API in public beta, letting developers build agents on a managed Codex harness while OpenAI handles session orchestration, context compaction, and recovery. Durable sessions carry work across turns with progress streaming, custom tools and MCP servers, and sandboxes either OpenAI-hosted or from your own infrastructure or a supported provider.

Prompt Cache Diagnostics is now generally available in the Responses API for GPT-5.6 and later supported models. It lets developers compare cache reuse against a previous response, identify reasons for cache misses, and follow troubleshooting guidance to improve cache reuse.

GPT-Rosalind (gpt-rosalind-research) is now generally available through the trusted-access program for approved internal life sciences research. Standard pricing is $5 per 1M input tokens, $0.50 per 1M cached input tokens, and $25 per 1M output tokens, with billing beginning October 5, 2026.

GPT Image 2.5 Sunburst and GPT Image 2.5 Flare are available for image generation and editing through the Image API and the Responses API image generation tool. Both support new xhigh and max quality settings and use GPT Image 2 token rates.

Prompt Cache Diagnostics is now generally available in the Responses API for GPT-5.6 and later supported models. It lets developers compare cache reuse against a previous response, identify reasons for cache misses, and follow troubleshooting guidance to improve cache reuse.

GPT Image 2.5 Sunburst and Flare are available for image generation and editing through the Image API and the Responses API image generation tool. Both support the new xhigh and max quality settings and use GPT Image 2 token rates.

GPT-6 Astra opens for general use, bringing new reasoning, coding, computer-use, and agent capabilities. It drops custom reasoning effort controls — only preset effort levels are supported — and requires tool calling through the Responses API.

The Responses API gains async tool results for long-running tool calls and new steering controls, including the ability to adjust reasoning effort mid-conversation and send in-flight updates over WebSocket.