Anthropic Python SDK
The official Python SDK released by Anthropic for calling the Claude series of large language model APIs. It supports enterprise-level permission management, a plugin marketplace, and Managed Agents, serving as the primary toolkit for developers integrating with Claude.
Core Facts
Timeline (last 90 days)
The Python SDK's built-in tool runner encapsulates the complete Agent loop, while the Claude Agent SDK further provides the agent harness capabilities that drive Claude Code.
The Anthropic official Python SDK's retry logic defaults to 2 retries, starting at 0.5 seconds and doubling up to 8 seconds, 75%-100% jitter, and honoring the retry-after header; in a 100-concurrency test only 40 succeeded.
During migration, it is recommended to update the package to version 1.0 via `pip install --upgrade anthropic`, and to search for all `import httpx` call sites and change them to use the corresponding httpx2 interfaces.
If other libraries in the project pin an older version of httpx, upgrading the Anthropic SDK may cause dependency resolution failures, and this needs to be verified separately in a virtual environment.
The Anthropic Python SDK 1.0 removed the Text Completions interface.
The Anthropic Python SDK 1.0 removed the temperature parameter.
The minimum Python version requirement for the Anthropic Python SDK 1.0 was raised to 3.10.
The underlying HTTP client of the Anthropic Python SDK 1.0 switched from httpx to httpx2.
For production systems, it is recommended to keep a rollback path to the old SDK version until the new version has run stably for a period of time.
At the API level, a new user-profiles-2026-09-04 beta value and an external_user_details field in user profiles have been added.
40 more timeline events
All Facts (20)
Anthropic's official Python SDK (anthropic-sdk-python) released version v1.11.0.
90%UnverifiedThe Python SDK's built-in tool runner encapsulates the complete Agent loop, while the Claude Agent SDK further provides the agent harness capabilities that drive Claude Code.
50%UnverifiedThe Anthropic official Python SDK's retry logic defaults to 2 retries, starting at 0.5 seconds and doubling up to 8 seconds, 75%-100% jitter, and honoring the retry-after header; in a 100-concurrency test only 40 succeeded.
50%UnverifiedThe underlying HTTP client of the Anthropic Python SDK 1.0 switched from httpx to httpx2.
50%UnverifiedThe minimum Python version requirement for the Anthropic Python SDK 1.0 was raised to 3.10.
50%UnverifiedIf other libraries in the project pin an older version of httpx, upgrading the Anthropic SDK may cause dependency resolution failures, and this needs to be verified separately in a virtual environment.
50%UnverifiedThe Anthropic Python SDK 1.0 removed the Text Completions interface.
50%UnverifiedFor production systems, it is recommended to keep a rollback path to the old SDK version until the new version has run stably for a period of time.
50%UnverifiedDuring migration, it is recommended to update the package to version 1.0 via `pip install --upgrade anthropic`, and to search for all `import httpx` call sites and change them to use the corresponding httpx2 interfaces.
50%UnverifiedThe Anthropic Python SDK 1.0 removed the temperature parameter.
50%UnverifiedAfter upgrading, developers can correct credential file permissions by running chmod 600 <credential file path> to eliminate errors.
50%Unverifiedv1.4.0 throws a clear error message when a user incorrectly passes an httpx object instead of the expected httpx2 object.
50%Unverifiedv1.4.0 fixes an abnormal merge logic for custom-code in the messages resource.
50%UnverifiedUpgrading from v1.3.0 to v1.4.0 is a backward-compatible minor version update with no breaking changes recorded.
50%UnverifiedInternal changes in v1.4.0 include bundling the mock server specification, cleaning up code comments, and fixing mypy unreachable errors in the detect-breaking-changes script.
50%Unverifiedv1.4.0 refreshes the platform model IDs in the example code.
50%UnverifiedTeams using the multi-workspace feature or relying on usage statistics for cost management are advised to upgrade to v1.4.0 as soon as possible.
50%UnverifiedDocumentation improvements in v1.6.0 include converting most docstrings to Markdown format and clarifying that the session_thread_id field is informational only.
50%Unverifiedv1.6.0 fixed the retry logic so the client respects Retry-After values exceeding 60 seconds, which previously would trigger premature retries due to an upper limit.
50%UnverifiedThe SDK raised the minimum version requirement for anyio to 4.1 and upgraded components such as aiohttp, pygments, and pytest in the development lock file.
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