LangGraph Streaming (Python) Overview An engineer ships to a token-level chat UI because it "seemed the most complete." Every single token causes the full graph state — message history, scratchpad, plan — to be re-sent and re-rendered. At 60 tokens/sec the browser overdraws, the React reconciler can't keep up, the tab freezes, and users blame the model. The correct answer was , which emits an delta per token (typically 5-50 bytes) — one token's worth of DOM work. This is pain-catalog entry P19 and it is the #1 LangGraph integration mistake in the 1.0 generation. Then the same UI ships to Clou…