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PyPI · #194 most downloaded on PyPI
The official Python library for the anthropic API
Last release 4 days ago
30 Sep 2026
Ships on a steady schedule
a new release about every 1 weeks
Nearly every release is documented
notes for 60 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
4 years old
223 releases · first in 2023
One column per quarter.
internal: avoid pytest-asyncio deprecation warning
docs: correct results return type
Full Changelog: v0.43.0...v0.43.1
vertex: remove deprecated HTTP client options
Full Changelog: v0.42.0...v0.43.0
cls fields (#817) (60e56a5)api: general availability updates
remove deprecated HTTP client options
Full Changelog: v0.40.0...v0.41.0
Omit type public (#772) (4ed0419)client: add ._request_id property to object responses
Full Changelog: v0.39.0...v0.40.0
cached-property dep (#762) (b9ffefe)client: remove legacy client.count_tokens() method
Full Changelog: v0.38.0...v0.39.0
client.count_tokens() method (#726)Full Changelog: v0.38.0...v0.39.0
client.count_tokens() & client.get_tokenizer() methods (#726)
client.beta.messages.count_tokens() API which supports newer models and all content functionality, such as images and PDFs.api: add message token counting & PDFs support
Full Changelog: v0.37.1...v0.38.0
bedrock: correct handling of messages beta
api: add new model and computer-use-2024-10-22 beta
Full Changelog: v0.36.2...v0.37.0
computer-use-2024-10-22 beta (dd93d87)types: remove misleading betas TypedDict property for the Batch API
allow header params to override default headers
client: avoid OverflowError with very large retry counts
Full Changelog: v0.35.0...v0.36.0
api: support disabling parallel tool use
Full Changelog: v0.34.2...v0.35.0
profile argument to client (#648) (6ea5fce)typing_extensions.overload instead of typing (#667) (153361d)## 0.34.2 (2024-09-04) Full Changelog: v0.34.1...v0.34.2 ### Chores * api: deprecate claude-1 model (eab07dc) * ci: also run pydantic v1 tests
client: fix parsing union responses when non-json is returned
client: add streaming helpers for prompt caching
ci: bump prism mock server version
client: add retries_taken to raw response class
Full Changelog: v0.32.0...v0.33.0
retries_taken to raw response class (43fb587)TypeAlias marker for type assignments (#621) (a4bff9c)add back compat alias for InputJsonDelta
Full Changelog: v0.31.2...v0.32.0
vertex: also refresh auth if there is no token
Full Changelog: v0.31.1...v0.31.2
bedrock: correct request options for retries
Full Changelog: v0.31.0...v0.31.1
next (#587) (f7e49f2)client: make request-id header more accessible
Full Changelog: v0.30.1...v0.31.0
build: include more files in sdist builds
vertex: add credentials argument
temporarily patch upstream version to fix broken release flow
api: add new claude-3-5-sonnet-20240620 model
readme: tool use is no longer in beta
Full Changelog: v0.28.0...v0.28.1
streaming: remove old event_handler API
Full Changelog: v0.27.0...v0.28.0
beta: streaming breakage due to breaking change in dependency
Full Changelog: v0.26.2...v0.27.0
tools: rely on pydantic's JSON parser instead of pydantic
api: add tool_choice param, image block params inside tool_result.content, and streaming for tool_use blocks
Full Changelog: v0.25.9...v0.26.0
tool_choice param, image block params inside tool_result.content, and streaming for tool_use blocks (#502) (e0bc274)types: correct type for InputSchema
client: log response headers in debug mode
Full Changelog: v0.25.7...v0.25.8
internal: update test helper function
internal: bump pyright to 1.1.359
internal: ban usage of lru_cache
bedrock: correct auth implementation
## 0.25.3 (2024-04-17) Full Changelog: v0.25.2...v0.25.3 ### Chores * bedrock: cache boto sessions
## 0.25.2 (2024-04-15) Full Changelog: v0.25.1...v0.25.2 ### Chores * internal: formatting
## 0.25.1 (2024-04-11) Full Changelog: v0.25.0...v0.25.1 ### Chores * fix typo
bedrock: add copy / with_options to bedrock client
Full Changelog: v0.24.0...v0.25.0
copy / with_options to bedrock client (8af7c41)client: add DefaultHttpxClient and DefaultAsyncHttpxClient
## 0.23.1 (2024-04-04) Full Changelog: v0.23.0...v0.23.1 ### Documentation * readme: mention tool use
## 0.23.0 (2024-04-04) Full Changelog: v0.22.1...v0.23.0 ### Features * api: tool use beta
types: correctly mark type as a required property in requests
client: increase default HTTP max_connections to 1000 and max_keepalive_connections to 100
Full Changelog: v0.21.3...v0.22.0
types: correct typo claude-2.1' to claude-2.1
readme: consistent use of sentence case in headings
internal: loosen input type for util function
vertex: api is no longer in private beta
Full Changelog: v0.20.0...v0.21.0
## 0.20.0 (2024-03-13) Full Changelog: v0.19.2...v0.20.0 ### Features * api: add haiku model (#390) (43b57fc) ### Documentation * readme: mention vert
vertex: use correct auth scopes
internal: add core support for deserializing into number response
api: add enum to model param for message
## 0.18.1 (2024-03-04) Full Changelog: v0.18.0...v0.18.1 ### Chores * readme: update bedrock example
## 0.18.0 (2024-03-04) Full Changelog: v0.17.0...v0.18.0 ### Features * bedrock: add messages API (#362) (5409be9) ### Chores * remove old examples
messages: add support for image inputs
Full Changelog: v0.16.0...v0.17.0
We've removed the beta namespace from the messages API.
Full Changelog: v0.15.1...v0.16.0
We've removed the beta namespace from the messages API.
To migrate to this version you'll just need to remove all .beta references, everything else is the same!
prevent crash when platform.architecture() is not allowed
Full Changelog: v0.15.0...v0.15.1
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