State

Root state accepted by decision models.

State is a string, JSON object, or JSON array. LangChain BaseMessage objects and message arrays can appear at the root or at any depth inside objects and arrays.

LangChain standard media blocks (for example { type: "image", data: ..., mimeType: ... }) may appear anywhere in the state. Each provider documents which media it supports and how it sends state its API cannot accept natively.