Streaming Callbacks And Safety

Integrator wants token-level events from a complex chain but only uses .stream, which yields chain output chunks, not granular per-node events.

Use astream_events (v2) to receive granular events (on_chat_model_stream for tokens, on_tool_start/on_tool_end, on_chain_*) across the whole chain. Filter by event type/name; do not conflate the coarse .stream output with the event stream.

While streaming, the integrator tries to execute a tool call from the first chunk, but the tool_calls arguments arrive incrementally and are incomplete.

Accumulate AIMessageChunks (they add together) until the tool_calls / tool_call_chunks are fully assembled before executing. Do not act on partial tool-call arguments; wait for the complete, parsed tool_calls on the aggregated message.

Integrator passes a provider API key as a plain constructor argument that gets logged via callbacks/metadata into traces.

Supply secrets via environment variables (or a secrets manager) read by the integration, not inline literals that land in metadata/traces; keep keys out of RunnableConfig metadata and logs. Redact any secret-shaped values before emitting telemetry.