Thinking Variant

The :thinking variant is retired. It turned reasoning on by default for models that had a separate reasoning entry; no model carries it now, and a model:thinking name answers 404.

Ask for reasoning on the request instead, with the reasoning parameter. It works across models and sets the reasoning effort or budget per call:

curl https://opendunes.com/v1/chat/completions \
  -H "Authorization: Bearer $OPENDUNES_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "anthropic/claude-sonnet-5",
    "reasoning": { "effort": "high" },
    "messages": [{ "role": "user", "content": "Prove that the square root of 2 is irrational." }]
  }'

Reasoning tokens are billed as output tokens, in DA. See Reasoning Tokens.