Class GthLangChainAgent

Invoke LLM with a message and runnable config. For streaming use #stream method, streaming is preferred if model API supports it. Please note that this when tools are involved, this method will anyway do multiple LLM calls within LangChain dependency.

Induce LLM to stream AI messages with a user message and runnable config. When stream is not appropriate use invoke.

Stream agent events as typed AgentStreamEvent objects. Yields text deltas, tool call lifecycle events, and tool results.

If a tool with metadata.client === true triggers interrupt(), the underlying graph throws GraphInterrupt; this generator catches it and ends cleanly so the caller's transport (e.g. AG-UI SSE) can finish the run with the tool call hanging. Resume the suspended graph via streamWithEventsResume on the same thread id.

Resume a graph that was suspended via interrupt() with the supplied value.

The runnable config must carry the same thread_id used when the graph was suspended (the checkpointer keys state by thread). The resume value is whatever the suspending tool needs back — for frontend-fulfilled tools this is the value the client sends in forwardedProps.command.resume.