openai-agents-python v0.21.0

Key Changes

This minor release does not introduce a known breaking SDK behavior change. The minor version bump is for the new provider-neutral testing APIs and the OpenAI Python v3 compatibility update.

Highlights:

• Added agents.testing, agents.realtime.testing, and agents.voice.testing utilities for deterministic Agent, Sandbox, Realtime, and Voice workflow tests without provider requests.
• Updated OpenAI provider compatibility to openai>=3.0.0,<4, including HTTPX2-aware request, response, transport, and exception handling.
• Hardened RunState interruption snapshots, recursive agent-tool approvals, max-turn finalization, streaming cleanup, and sensitive-error redaction.
• Improved MCP lifecycle snapshot isolation and added configurable retry backoff ceilings.
• Added Sandbox Runloop existing-secret support and tightened view-image path grants.
• Added stricter Voice validation for invalid channels, frame rates, incomplete multichannel frames, and non-finite audio rates.

What’s Changed

• feat: support OpenAI Python 3 and HTTPX2 by @seratch in https://github.com/openai/openai-agents-python/pull/4380
• feat: add scripted model test utilities by @seratch in https://github.com/openai/openai-agents-python/pull/4362
  • fix: freeze public testing module contracts by @seratch in https://github.com/openai/openai-agents-python/pull/4386
  • fix: freeze public testing API state contracts by @seratch in https://github.com/openai/openai-agents-python/pull/4404
  • fix(core): preserve scripted annotation streaming across Python SDK releases by @apcha-oai in https://github.com/openai/openai-agents-python/pull/4422
• fix(core): isolate interruption results by @hsusul in https://github.com/openai/openai-agents-python/pull/4384
• fix(core): close the model stream when a streamed turn ends in a terminal failure by @Luccacvb in https://github.com/openai/openai-agents-python/pull/4366
• fix(core): redact tool output value from output-type validation errors by @hsusul in https://github.com/openai/openai-agents-python/pull/4396
• fix(core): align Responses parallel tool calls with converted tools by @seratch in https://github.com/openai/openai-agents-python/pull/4405
• fix(core): max-turn handler session semantics by @seratch in https://github.com/openai/openai-agents-python/pull/4412
• fix(core): detach RunState interruption snapshots by @seratch in https://github.com/openai/openai-agents-python/pull/4409
• fix(core): isolate RunState checkpoint tool decisions by @seratch in https://github.com/openai/openai-agents-python/pull/4413
• fix(core): resume recursive agent tool approvals by @seratch in https://github.com/openai/openai-agents-python/pull/4414
• fix(mcp): stop handing the tools cache to callers by @chinmayv095 in https://github.com/openai/openai-agents-python/pull/4424
• fix(mcp): protect manager lifecycle state snapshots by @seratch in https://github.com/openai/openai-agents-python/pull/4407
• fix(mcp): isolate manager lifecycle results by @hsusul in https://github.com/openai/openai-agents-python/pull/4368
• fix(mcp): add configurable retry backoff ceiling by @seratch in https://github.com/openai/openai-agents-python/pull/4379
• fix(realtime): handle non-finite audio rates by @hsusul in https://github.com/openai/openai-agents-python/pull/4419
• fix(sandbox): expose the scripted sandbox session type by @seratch in https://github.com/openai/openai-agents-python/pull/4406
• fix(sandbox): apply stacked anchors sequentially by @seratch in https://github.com/openai/openai-agents-python/pull/4369
• fix(sandbox): snapshot HTTP proxy headers by @hsusul in https://github.com/openai/openai-agents-python/pull/4397
• fix(sandbox): snapshot per-op audit policies by @hsusul in https://github.com/openai/openai-agents-python/pull/4398
• fix(sandbox): honor view_image extra path grants by @sylvesterkaczmarek in https://github.com/openai/openai-agents-python/pull/4417
• fix(sessions): handle zero conversation history limits by @hsusul in https://github.com/openai/openai-agents-python/pull/4365
• fix(voice): honor WAV sample width by @FU-max-boop in https://github.com/openai/openai-agents-python/pull/4361
• fix(voice): reject incomplete multichannel audio frames by @seratch in https://github.com/openai/openai-agents-python/pull/4370
• fix(voice): reject non-positive audio channels by @hansu650 in https://github.com/openai/openai-agents-python/pull/4372
• fix(voice): reject non-positive audio frame rates by @hsusul in https://github.com/openai/openai-agents-python/pull/4382
• fix(voice): stop buffering audio when audio tracing is disabled by @rxits in https://github.com/openai/openai-agents-python/pull/4411
• fix(extensions): gate AnyLLM parallel tool calls on converted tools by @weivwang in https://github.com/openai/openai-agents-python/pull/4363
• fix(extensions): preserve resume argument ordering by @viyatb-oai in https://github.com/openai/openai-agents-python/pull/4400
• fix(extensions): let managed_secrets reference existing Runloop secrets by @xumaple in https://github.com/openai/openai-agents-python/pull/4378

Documentation & Other Changes

• docs: synchronize v0.20.0 features by @seratch in https://github.com/openai/openai-agents-python/pull/4280
• docs: clarify PGP key location by @jaideeppyne in https://github.com/openai/openai-agents-python/pull/4371
• test: order test spans by start sequence, not by started_at alone by @ErenAta16 in https://github.com/openai/openai-agents-python/pull/4392
• release: 0.21.0 by @seratch in https://github.com/openai/openai-agents-python/pull/4387

New Contributors

• @FU-max-boop made their first contribution in https://github.com/openai/openai-agents-python/pull/4361
• @weivwang made their first contribution in https://github.com/openai/openai-agents-python/pull/4363
• @jaideeppyne made their first contribution in https://github.com/openai/openai-agents-python/pull/4371
• @hansu650 made their first contribution in https://github.com/openai/openai-agents-python/pull/4372
• @xumaple made their first contribution in https://github.com/openai/openai-agents-python/pull/4378
• @viyatb-oai made their first contribution in https://github.com/openai/openai-agents-python/pull/4400
• @ErenAta16 made their first contribution in https://github.com/openai/openai-agents-python/pull/4392
• @apcha-oai made their first contribution in https://github.com/openai/openai-agents-python/pull/4422
• @sylvesterkaczmarek made their first contribution in https://github.com/openai/openai-agents-python/pull/4417

Full Changelog: https://github.com/openai/openai-agents-python/compare/v0.20.0…v0.21.0

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Source openai/openai-agents-python · v0.21.0 · 2026-08-15 · upstream release

Mirrored verbatim for indexing. All rights belong to the upstream project.