v4.0.0

Breaking changes and migration guide

Please see our documentation.

Other changes

• chore(deps-dev): bump werkzeug from 3.1.5 to 3.1.6 by @dependabot[bot] in https://github.com/langfuse/langfuse-python/pull/1531
• chore: upgrade ruff + merge configurations by @akx in https://github.com/langfuse/langfuse-python/pull/1535
• fix(media): reuse httpx client for requests by @hassiebp in https://github.com/langfuse/langfuse-python/pull/1537
• feat!: prepare v4 release by @hassiebp in https://github.com/langfuse/langfuse-python/pull/1486
• feat(api): update API spec from langfuse/langfuse 784ab09 by @langfuse-bot in https://github.com/langfuse/langfuse-python/pull/1538
• fix(media): retry failed uploads by @hassiebp in https://github.com/langfuse/langfuse-python/pull/1540
• feat(api): update API spec from langfuse/langfuse 25b5139 by @langfuse-bot in https://github.com/langfuse/langfuse-python/pull/1543
• chore(deps-dev): bump langgraph-checkpoint from 3.0.0 to 4.0.0 by @dependabot[bot] in https://github.com/langfuse/langfuse-python/pull/1541
• feat(api): update API spec from langfuse/langfuse a93f65a by @langfuse-bot in https://github.com/langfuse/langfuse-python/pull/1545
• fix(langchain): skip priority-tier keys when subtracting token detail counts by @Br1an67 in https://github.com/langfuse/langfuse-python/pull/1549
• fix(experiment): replace escaped newlines with actual newlines in format output by @Br1an67 in https://github.com/langfuse/langfuse-python/pull/1547
• fix(openai): remove unreachable None type assignments for OpenAI classes by @Br1an67 in https://github.com/langfuse/langfuse-python/pull/1546
• Add handling for invalid tool calls in CallbackHandler by @deershark in https://github.com/langfuse/langfuse-python/pull/1550
• fix: apply stricter early routing for base64 media to prevent SSE dat… by @MoonSangJin in https://github.com/langfuse/langfuse-python/pull/1544
• chore: unify logging usage by @akx in https://github.com/langfuse/langfuse-python/pull/1539
• fix(client): pass release variable to span clients by @hassiebp in https://github.com/langfuse/langfuse-python/pull/1518
• feat(api): update API spec from langfuse/langfuse 2eaf041 by @langfuse-bot in https://github.com/langfuse/langfuse-python/pull/1556
• chore(deps-dev): bump langgraph from 1.0.9 to 1.0.10rc1 by @dependabot[bot] in https://github.com/langfuse/langfuse-python/pull/1560

New Contributors

• @akx made their first contribution in https://github.com/langfuse/langfuse-python/pull/1535
• @Br1an67 made their first contribution in https://github.com/langfuse/langfuse-python/pull/1549
• @deershark made their first contribution in https://github.com/langfuse/langfuse-python/pull/1550
• @MoonSangJin made their first contribution in https://github.com/langfuse/langfuse-python/pull/1544

Full Changelog: https://github.com/langfuse/langfuse-python/compare/v3.14.5...v4.0.0