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npm · #3914 most downloaded on npm
Client library to connect to the LangSmith Observability and Evaluation Platform.
Last release today
02 Oct 2026
Ships on a steady schedule
a new release about every 9 days
Some releases are documented
notes for 32 of the last 60 stable releases
3 versions withdrawn
withdrawn after publishing
3 years old
458 releases · first in 2023
One column per quarter.
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feat(js): Add method to get size of annotation queue by @tendev-liam in https://github.com/langchain-ai/langsmith-sdk/pull/1377
pydantic model serialization consistent regardless of surrogates. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1405Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.10...v0.2.11
feat: Instrument wrapper for OpenAI structured outputs by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1373
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.9...v0.2.10
python[patch]: handle deployments without attachments support by @baskaryan in https://github.com/langchain-ai/langsmith-sdk/pull/1371
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.8...v0.2.9
feat: Make size_limit (max run count per batch) globally configurable via env var by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.7...v0.2.8
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fix: Separate rust and compressed ingestion paths by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1355
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.6...v0.2.7
docs: update ref for list_examples by @isahers1 in https://github.com/langchain-ai/langsmith-sdk/pull/1346
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.5...v0.2.6
perf: [LS-2561] Stream compress multipart runs by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1316
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.4...v0.2.5
Improve the error message for tag and version mismatch error case. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1308
Update operations into Create operations in the same batch. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1333Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.3...v0.2.4
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fix: multiple evaluators don't consume the reader by @isahers1 in https://github.com/langchain-ai/langsmith-sdk/pull/1322
Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.2...v0.2.3
Fix formatting in Rust tracing client. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1296
update_run() method. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1314Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.1...v0.2.2
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chore: increase server info request timeout by @bvs-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1294
thiserror from v1 to v2. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1287Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.2.0...v0.2.1
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Drop outdated/vulnerable dependencies by using a newer multipart library by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1288
sonic_rs and switch to serde_json. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1286langsmith_nodejs Rust code. by @obi1kenobi in https://github.com/langchain-ai/langsmith-sdk/pull/1291Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.1.147...v0.2.0
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