npm · #3914 most downloaded on npm

langsmith

0.10.525M downloads/molangchain-ai/langsmith-sdk ↗New releases in your daily digest, changelog included.

Client library to connect to the LangSmith Observability and Evaluation Platform.

Last release 9 days ago
21 Sep 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3 versions withdrawn
withdrawn after publishing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
455 releases · first in 2023

Release timeline

455 releases since 2023

2023202420252026

20232026

One column per quarter.

Releases

0.5.86 Mar 2026
Nothing published for this version
0.5.725 Feb 2026
Nothing published for this version
0.5.622 Feb 2026
Nothing published for this version
0.5.521 Feb 2026
Nothing published for this version
0.5.4

0.5.210 Feb 2026

feat(js): Add support for tracing AI SDK 6 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2237

What's Changed

feat(js): Add support for tracing AI SDK 6 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2237
fix(js): Remove default Jestlike timeout by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2243
feat(js): Add support for tracing tool loop agent by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2244
feat: Replace UUID5 with deterministic UUID7 for replicas by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/2249
feat: add prompt caching to python sdk by @langchain-infra in https://github.com/langchain-ai/langsmith-sdk/pull/2246
feat: add js prompt caching by @langchain-infra in https://github.com/langchain-ai/langsmith-sdk/pull/2251
fix(claude): correctly parse llm and tool inputs in claude agent sdk by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/2255
bump(python): 0.5.2 by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/2256

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.5.1...v0.5.2

Open source →

0.5.110 Feb 2026

feat(openai): Add use responses API to OpenAI wrapper by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2218

What's Changed

feat(openai): Add use responses API to OpenAI wrapper by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2218
chore(py): Fix Python integration tests by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2219
feat(js): Add invocation param tracing for OpenAI responses wrapper in JS by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2220
Ignore empty string by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/2225
remove duplicate patch from claude agent sdk by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/2189
fix(js): Fix JS Memory Leak clean child_runs by @amodelaweb in https://github.com/langchain-ai/langsmith-sdk/pull/2228
fix(js): Make traced async iterators call finally on success by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2230
release(js): 0.4.1 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2231
fix(js): Avoid waiting for child runs to complete if parent throws an error by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2232
release(js): 0.4.2 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2233
fix(js): Remove unnecessary promise skip on error by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2234
Fix timestamp ordering violation in RunTree.create_child by @loganrosen in https://github.com/langchain-ai/langsmith-sdk/pull/2240
fix(python): pull prompt for newer langchain_core by @eyurtsev in https://github.com/langchain-ai/langsmith-sdk/pull/2239

New Contributors

@amodelaweb made their first contribution in https://github.com/langchain-ai/langsmith-sdk/pull/2228
@loganrosen made their first contribution in https://github.com/langchain-ai/langsmith-sdk/pull/2240

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.5.0...v0.5.1

Open source →

0.5.09 Feb 2026

feat(py,js): Python 0.5, JS 0.4 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2182

What's Changed

feat(py,js): Python 0.5, JS 0.4 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2182
js: Ensures parent traceables always finish after children in https://github.com/langchain-ai/langsmith-sdk/pull/2094
py: Make evaluator target function traces only trace inputs instead of nested inputs outputs reference_outputs (BREAKING) in https://github.com/langchain-ai/langsmith-sdk/pull/2074
py,js: Change default ingest to multipart instead of single run (BREAKING) in https://github.com/langchain-ai/langsmith-sdk/pull/2206
js: Omit raw HTTP info when tracing AI SDK runs (BREAKING) in https://github.com/langchain-ai/langsmith-sdk/pull/2207
py,js: Remove legacy evaluators (BREAKING) in https://github.com/langchain-ai/langsmith-sdk/pull/2144
js: Remove legacy AI SDK exporter and wrapAIModel (BREAKING) in https://github.com/langchain-ai/langsmith-sdk/pull/2210
js: Make traceables that receive iterables as inputs use a single POST instead of the typical POST + PATCH flow in https://github.com/langchain-ai/langsmith-sdk/pull/2209
release(js): 0.4.0 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2216
release(py): 0.5.0 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/2217

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.60...v0.5.0

Open source →

0.4.1231 Jan 2026

fix(ci): Allow 429s for markdown link checks in CI by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1895

What's Changed

fix(ci): Allow 429s for markdown link checks in CI by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1895
feat(py): add Run.latency by @baskaryan in https://github.com/langchain-ai/langsmith-sdk/pull/1745
fix(js): Ensure dotted order and start time is always greater than parent start time for legacy AI SDK exporter by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1903
chore(python): Remove langsmith dotted order attribute from otel integration by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1904

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.11...v0.4.12

Open source →

0.4.1130 Jan 2026

chore: Run ruff by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1894

What's Changed

chore: Run ruff by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1894
Adopt pagination to list_shared_examples to ensure all data returned by @EugeneJinXin in https://github.com/langchain-ai/langsmith-sdk/pull/1893
feat(python, js): Support tracing to multiple orgs/workspaces by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1899

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.10...v0.4.11

Open source →

0.4.1026 Jan 2026

feat(python): Add replica endpoints support to Python SDK by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1877

What's Changed

feat(python): Add replica endpoints support to Python SDK by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1877
feat(python): Add distributed tracing with sliced traces for child projects by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1884
feat(py): return feedback notes in get_test_results by @baskaryan in https://github.com/langchain-ai/langsmith-sdk/pull/1873
chore: Convert dev workflow to uv by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1885
chore(py): Format lockfile by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1887
fix(python): Remove upper bound for OpenAI agents by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1883
fix(py): Make replica tests properly restore env vars to reduce flakiness by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1888
fix(py): Missed test causing flakes by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1889
fix(py): Reset env causing unit test flake by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1890
Remove black dependency and update lock file by @EugeneJinXin in https://github.com/langchain-ai/langsmith-sdk/pull/1892
feat(py): Adds new cached_hosts parameter to vcrpy caching by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1878
fix(py): Remove monkeypatching and ensure env var cache is cleared by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1891
release(py): 0.4.10 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1896

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.9...v0.4.10

Open source →

0.4.925 Jan 2026

feat(js): Update AI SDK tracing for v5 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1863

What's Changed

feat(js): Update AI SDK tracing for v5 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1863
feat: Configure by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/1859
fix (js): include env var metadata in patch by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/1867
release(js): 0.3.48 by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/1868
feat(js): Respect LANGSMITH_OTEL_ENABLED env var, allow skipping global context manager setup, skip non-traceable spans by default by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1870
feat(js): Adds dotted order to traced OTEL spans by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1876
chore(python): deflake ci by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1872
fix(js): Respect Anthropic 1h caching usage for AI SDK 5 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1879
patch(python, js): Fix sampling logic for patch runs by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1881

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.8...v0.4.9

Open source →

0.4.822 Jan 2026

fix(python): Fix update_examples improperly overriding inputs/outputs for multipart endpoint by @jacoblee93 in https://github.com/langchain-ai/langsmi

What's Changed

fix(python): Fix update_examples improperly overriding inputs/outputs for multipart endpoint by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1860

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.7...v0.4.8

Open source →

0.4.715 Jan 2026

fix(js): Make readDataset throw if empty string is passed by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1853

What's Changed

fix(js): Make readDataset throw if empty string is passed by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1853
fix(js): Fallback to parent run id if parent run is not present in run trees loaded from LangChain by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1854
Safer module check by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/1857

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.6...v0.4.7

Open source →

0.4.614 Jan 2026

If stream fails, fallback to buffered body request by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1845

What's Changed

If stream fails, fallback to buffered body request by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1845
fix(js): Fix replica updates by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1848
feat(js): Support feedback attribution for OTEL evaluations by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1847
fix(js): Propagate microseconds added in dotted order conversion to run tree start time by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1849
fix(js): Respect project names set at runtime for OTEL exported traces by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1850
feat(python): Add repetitions support to pytest, rename in JS by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1852

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.5...v0.4.6

Open source →

0.4.56 Jan 2026

feat(js): Add OTEL support by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1814

What's Changed

feat(js): Add OTEL support by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1814
feat(js): Export passed AI SDK metadata as LangSmith metadata by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1819
Reduce zstd compression level to 1 by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1820
feat(js): Add transform span method to exporter, allow setting run name by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1821
fix(js): Use context placeholder to preserve LangChain context variables even if tracing is disabled by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1822
fix(js): Fix types and add responses and completions.parse support for wrapOpenAI by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1823
release(js): 0.3.38 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1824
fix(js): Fix AI SDK token counting issues for legacy exporter by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1825
feat(js): Make traced AI SDK runs respect provider metadata by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1826
feat(js): Add reference_example_id attribute to OTEL runs by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1836
[open-swe] fix: improve serialization of Maps and complex objects in traces by @open-swe[bot] in https://github.com/langchain-ai/langsmith-sdk/pull/1835
release(js): 0.3.41 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1837
fix(js): Add endpoint shim to example upload by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1839
Add runs endpoints env to replicas by @hinthornw in https://github.com/langchain-ai/langsmith-sdk/pull/1830
release(js): 0.3.42 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1842
feat(python): Populate example metadata in pytest, prefix experiment runs with ls_example by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1840

New Contributors

@open-swe[bot] made their first contribution in https://github.com/langchain-ai/langsmith-sdk/pull/1835

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.4...v0.4.5

Open source →

0.4.330 Dec 2025

feat(js): Allow suppressing circular JSON warnings by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1815

What's Changed

feat(js): Allow suppressing circular JSON warnings by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1815
fix(py): loosen pydantic dep by @baskaryan in https://github.com/langchain-ai/langsmith-sdk/pull/1816

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.2...v0.4.3

Open source →

0.4.222 Dec 2025

Add agent instructions for Python SDK by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1776

What's Changed

Add agent instructions for Python SDK by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1776
Fix some issues w running codex in this repo by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1777
Fix race for cached client initialization by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1778
Handle missing attachment files gracefully by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1782
fix(js): Fix JSDom check for Node 22 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1784
Cache request settings for Client by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1787
chore: auto-label issues with 'sdk' label by @madams0013 in https://github.com/langchain-ai/langsmith-sdk/pull/1791
Store only the first new_token event by @nfcampos in https://github.com/langchain-ai/langsmith-sdk/pull/1779
fix(js): Pass events through on run create by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1794
fix(js): Avoid overwriting runtime if already set by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1795
feat(js): Add replica support for JS by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1796
release(js): 0.3.32 by @jacoblee93 in https://github.com/langchain-ai/langsmith-sdk/pull/1797
add util for getting project name from env var by @lc-arjun in https://github.com/langchain-ai/langsmith-sdk/pull/1801
patch[python]: Only set replica updates on patch by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1798
feat[python]: Trace to multiple projects with distributed tracing by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1804
feat[python]: Enable OpenTelemetry trace context propagation by @angus-langchain in https://github.com/langchain-ai/langsmith-sdk/pull/1805
chore(deps): bump protobuf from 5.29.4 to 5.29.5 in /python by @dependabot in https://github.com/langchain-ai/langsmith-sdk/pull/1807
feat(py): add evaluate(..., error_handling="ignore") by @baskaryan in https://github.com/langchain-ai/langsmith-sdk/pull/1774

New Contributors

@lc-arjun made their first contribution in https://github.com/langchain-ai/langsmith-sdk/pull/1801

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.4.1...v0.4.2

Open source →

0.4.016 Dec 2025

feat: OTEL_ENABLED mode sends to both otel and ls, while allowing otel only through OTEL_ONLY var by @EugeneJinXin in https://github.com/langchain-ai/

What's Changed

feat: OTEL_ENABLED mode sends to both otel and ls, while allowing otel only through OTEL_ONLY var by @EugeneJinXin in https://github.com/langchain-ai/langsmith-sdk/pull/1762

New Contributors

@EugeneJinXin made their first contribution in https://github.com/langchain-ai/langsmith-sdk/pull/1762

Full Changelog: https://github.com/langchain-ai/langsmith-sdk/compare/v0.3.45...v0.4.0

Open source →