# Anthropic Python SDK v1.0.0

- Product: Anthropic Python SDK (https://whatsnew.fyi/product/anthropic-sdk-python)
- Vendor: Anthropic
- Date: 2026-08-20
- Version: v1.0.0
- Original notes: https://github.com/anthropics/anthropic-sdk-python/releases/tag/v1.0.0
- Permalink: https://whatsnew.fyi/product/anthropic-sdk-python/releases/v1.0.0

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **changed** — Upgrade to httpx2 with minor breaking changes
- **fixed** — Stop warning about output_format= on the parse/stream/tool_runner helpers

##### 1.0.0 (2026-08-20)

Full Changelog: [v0.125.0...v1.0.0](https://github.com/anthropics/anthropic-sdk-python/compare/v0.125.0...v1.0.0)

###### ⚠ BREAKING CHANGES

* **client:** upgrade to httpx2 and some minor breaking changes. See MIGRATION.md for details

###### Features

* **client:** upgrade to httpx2 and some minor breaking changes. See MIGRATION.md for details ([33e2967](https://github.com/anthropics/anthropic-sdk-python/commit/33e296749dda59c3b9af85d9bee37ae241b92a28))


###### Bug Fixes

* **beta:** stop warning about `output_format=` on the parse/stream/tool_runner helpers ([59bf261](https://github.com/anthropics/anthropic-sdk-python/commit/59bf26106d3d66cef54b926aeae4268846bf13f2))


###### Chores

* **streaming:** restore the original event imports in lib/streaming/_types.py ([87e9e01](https://github.com/anthropics/anthropic-sdk-python/commit/87e9e0157c08ad4b9bb4c44081171285499b1aa3))


###### Documentation

* **examples:** use adaptive thinking in thinking examples ([b5870af](https://github.com/anthropics/anthropic-sdk-python/commit/b5870afda154cc12ab15fad5ca6f53a280e09ee3))