# POST /api/public/traces stops working

Calls to POST /api/public/traces on Langfuse API stop working on November 16, 2026.

Starting November 16, 2026, the POST /api/public/traces endpoint stops working on cloud.langfuse.com. Calls to this endpoint will fail after that date, as trace-ingestion paths are served only until then.

- API: Langfuse API (cloud.langfuse.com)
- Kind: Endpoint removal
- Announced: August 17, 2026
- Takes effect: November 16, 2026
- Calls after that day: fail
- Calls it hits: `POST /api/public/traces`
- Source: [Announcement](https://langfuse.com/faq/all/deprecated-api-migration)
- Page: https://www.okapi.bot/providers/langfuse/breaking-changes/post-api-public-traces-stops-working/

## What to use instead

Send traces to POST /api/public/otel/v1/traces (OTLP/HTTP) with the x-langfuse-ingestion-version: 4 header, or upgrade the SDK to Python 4.7.0, JS/TS 5.4.0 or later.

## Langfuse API's words

> Langfuse Cloud serves these trace-ingestion paths until November 16, 2026