Sequential Tool Calls In LangGraph
Explore sequential tool calls, chaining outputs step by step for compound tasks solved through reasoning.
We'll cover the following...
At the end of the last lesson, we saw how LangGraph can orchestrate multiple tools in a single workflow. But tools do not always work in isolation. Often, the output from one tool becomes the input for another, creating a sequence of calls that unfold step by step.
Think of it like this: the AI host sometimes needs two guests to collaborate at our dinner party. Suppose a guest asks: Translate the weather in Paris into French. The host first turns to the weather forecaster, who replies: The weather in Paris is sunny. Then the host hands that statement to the translator, who provides the French version. The host returns with the final answer only after both specialists have spoken.
We will build a LangGraph workflow where the AI can call several tools in sequence, passing outputs along the way until the task is complete.
Why do we need sequential tool calls?
Many real-world tasks are composite: they cannot be solved in a single step.
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