LangChain: Stream Events v3 Protocol and Partner Updates
LangChain shipped version 3 of the stream_events protocol with improved typing and async support, while adding multimodal capabilities to MistralAI and new features to OpenRouter and Fireworks integrations.
Duration: PT2M18S
Episode overview
This episode is a short developer briefing from LangChain.
It explains recent repository work in plain language.
- Show: LangChain
- Published: 2026-05-01T00:00:00Z
- Audio duration: PT2M18S
Transcript excerpt
This excerpt keeps the crawler page concise. Listen to the episode or use the RSS feed for the full update.
Good morning, this is your LangChain developer briefing for May 1st, 2026.
The major release today is nick-hollon-lc's stream_events version 3 protocol for langchain-core. This introduces a new overload on BaseChatModel and Runnable with hybrid async result handling that maintains backward compatibility for v1 and v2 callers while exposing the v3 typed event stream. The implementation adds…
sydney-runkle merged improvements to tool schema handling, introducing ToolSchema as a root cache to replace three independent cached properties with a single dataclass. This change also switches from TypedDict conversion to TypeAdapter for cleaner schema management.
Several partner integrations received significant updates. choudhary-akash added image input support for MistralAI human messages, fixing multimodal inputs that were previously rejected due to API format differences. X-iZhang resolved OpenRouter streaming issues by implementing reasoning_details merging to prevent…
mdrxy contributed multiple partner enhancements: service_tier support for ChatFireworks matching ChatOpenAI functionality, and session_id and trace fields for OpenRouter to support their broadcast feature for request…
Infrast…
Nearby episodes from LangChain
- Critical Security Patch and Hub Deprecation
- Schema Resolution Fix and Alpha Release
- Security Fortress - Hardening Against Untrusted Code
- Weekly Recap - Streaming Enhancements and Partner Integrations
- Human-in-the-Loop Enhancements and Fireworks Vision Fix
- Perplexity Embeddings Integration and Version Updates
- Weekly Recap - Streaming Reliability & Performance
- Major Streaming Overhaul and Release Updates