Non-default `temperature`, `top_p`, or `top_k` returns a 400 error on Claude Opus 4.8.

Custom sampling parameters now fail on Claude Opus 4.8, making default sampling the safe path.

This matches Claude Opus 4.7 behavior, so integrations carrying custom sampling parameters need migration-guide handling.

• Jul 18, 2026Anthropic model card shows no readable text change in this diff.
• Jul 18, 2026Anthropic pricing page removed the Claude plan recommendation questionnaire content.
• Jul 18, 2026ChatGPT scheduled tasks gained a sidebar page for viewing, managing, and editing active tasks.

This is the world we build in. It moves this fast. We move with it.