temperature

Controls randomness in responses (0–1). Lower values produce more deterministic output; higher values produce more varied responses.

Syntax

claude-api

{ temperature: 0.0 } // to { temperature: 1.0 }

Example

claude-api

// Deterministic — good for code/facts:
const precise = await client.messages.create({
  model: "claude-opus-4-5",
  max_tokens: 512,
  temperature: 0,
  messages: [{ role: "user", content: "What is 2+2?" }]
});

// Creative — good for writing:
const creative = await client.messages.create({
  temperature: 0.9, ...
});