Claude-Api on Tokenisehttps://tokenise.rosvetic.com/tags/claude-api/Recent content in Claude-Api on TokeniseHugoen-gbSat, 24 Oct 2026 11:02:00 +0000Claude API version 2026-10-21 returns a 400 for temperature. Find every call before the SDK bump doeshttps://tokenise.rosvetic.com/posts/claude-api-version-2026-10-21-upgrade-audit/Sat, 24 Oct 2026 11:02:00 +0000https://tokenise.rosvetic.com/posts/claude-api-version-2026-10-21-upgrade-audit/<p>On 21 October 2026 Anthropic shipped API version <code>2026-10-21</code>, the first new version since <code>2023-06-01</code>, and it isn&rsquo;t a drop-in. A request that sends <code>temperature</code>, <code>top_p</code> or <code>top_k</code> returns a 400 error, even at the default value. Eight official libraries released new major versions the same day, and each one sends the new version by default.</p>