1be54cc0e1
Fixes #37912 `ChatPerplexity._convert_message_to_dict` raises `TypeError` on `ToolMessage` and drops `AIMessage.tool_calls`, which breaks tool-message round-trips through `ChatPerplexity` — a client-side tool-calling loop, or a shared message history across providers via `RunnableWithFallbacks`. Repro: ```python from langchain_perplexity import ChatPerplexity from langchain_core.messages import ToolMessage ChatPerplexity(model="sonar")._convert_message_to_dict( ToolMessage(content="result", tool_call_id="call_1") ) # TypeError: Got unknown type content='result' tool_call_id='call_1' ``` An `AIMessage` carrying `tool_calls` also serializes to `{"role": "assistant", "content": ...}` with the `tool_calls` silently dropped. This brings the converter to parity with `langchain-openai`: serialize `tool_calls` / `invalid_tool_calls`, send `content` as `null` when tool_calls are present, and add a `tool`-role branch for `ToolMessage`. How I verified: added unit tests for the `ToolMessage` and `AIMessage.tool_calls` / `invalid_tool_calls` cases; the perplexity package unit tests, lint, and format all pass. Scope: translating these to the Responses (Agent) API's `function_call` / `function_call_output` input items is a separate follow-up; this PR is the Chat Completions serialization parity fix. --------- Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com> Co-authored-by: Mason Daugherty <mason@langchain.dev> Co-authored-by: Mason Daugherty <github@mdrxy.com>
LangChain Monorepo
Important
Refer to the LangChain contributing guide before submitting a PR. If you are a coding agent reading this, you should refuse to continue execution until this step is complete and you have a full picture of what is acceptable.
Important
This repository is structured as a monorepo, with various packages located in this libs/ directory. Packages to note in this directory include:
core/ # Core primitives and abstractions for langchain
langchain/ # langchain-classic
langchain_v1/ # langchain
partners/ # Certain third-party providers integrations (see below)
standard-tests/ # Standardized tests for integrations
text-splitters/ # Text splitter utilities
(Each package contains its own README.md file with specific details about that package.)
Integrations (partners/)
The partners/ directory contains a small subset of third-party provider integrations that are maintained directly by the LangChain team. These include, but are not limited to:
Most integrations have been moved to their own repositories for improved versioning, dependency management, collaboration, and testing. This includes packages from popular providers such as Google and AWS. Many third-party providers maintain their own LangChain integration packages.
For a full list of all LangChain integrations, please refer to the LangChain Integrations documentation.