{"version":"2.1.285","anchor":"model-access-background-tier-check-for-bedrockvertex","canonical_anchor":"model-access-background-tier-check-for-bedrockvertex","heading":"Background check for model access on Bedrock, Vertex and Mantle","tier":"notice","area":"Models","url":"https:\/\/changelogs.core-directive.com\/v\/2.1.285\/e\/model-access-background-tier-check-for-bedrockvertex","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.285","markdown":"### Background check for model access on Bedrock, Vertex and Mantle\n\nWhen a model is denied on Bedrock, Vertex or Mantle, Claude Code now checks lower model tiers in the background and remembers which ones work\n\n**Unclear.** It is not clear what starts the background check or whether a setting controls it.\n\n**What**\n\nIf you use Claude through Amazon Bedrock, Google Vertex or Mantle, and a model request is denied or refused, Claude Code now checks in the background whether lower model tiers are available to you. It remembers the results of these checks.\n\nThere is also a new start-up check. It builds a tiny test request, one token long, that includes Claude Code's billing details. A token is a small piece of text. If Claude Code cannot build this request, it logs a warning.\n\n**Why**\n\nThis looks like groundwork for falling back to a model you can use when your first choice is refused on one of these cloud providers.\n\n- Area: Models\n- Tier: You'll notice\n- Useful: 3\/5\n- Signal: 2\/5"}