Claude 5 Sonnet Migration Guide

// These parameters are ignored on Claude 5 Sonnet
{
  "model": "anthropic/claude-sonnet-5",
  "temperature": 0.5,
  "top_p": 0.9,
  "top_k": 50,
  "messages": [{ "role": "user", "content": "Hello" }]
}

// Opt in to adaptive thinking — the only thinking mode on Sonnet 5
{
  "model": "anthropic/claude-sonnet-5",
  "reasoning": { "enabled": true },
  "messages": [{ "role": "user", "content": "Solve this problem step by step" }]
}

// reasoning.max_tokens is ignored (adaptive used)
{
  "model": "anthropic/claude-sonnet-5",
  "reasoning": { "enabled": true, "max_tokens": 10000 },
  "messages": [{ "role": "user", "content": "Hello" }]
}
// ↑ Equivalent to just { "reasoning": { "enabled": true } }

// reasoning.effort maps to output_config.effort (thinking stays adaptive)
{
  "model": "anthropic/claude-sonnet-5",
  "reasoning": { "enabled": true, "effort": "low" },
  "messages": [{ "role": "user", "content": "Hello" }]
}
// ↑ Equivalent to { "reasoning": { "enabled": true }, "verbosity": "low" }

{
  "model": "anthropic/claude-sonnet-5",
  "verbosity": "xhigh"
}

{ "model": "anthropic/claude-sonnet-5", "verbosity": "xhigh" }