langchain-openai 1.4.3: What's New in the Latest Release [August 2026] The langchain-openai 1.4.3 release, published on August 10, 2026, filters invalid tool calls out of assistant content during v1-to-Chat-Completions conversion, so OpenAI-compatible endpoints stop reje... AI agents langchain openai python tool calling 11-Aug-2026 0 22