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Model error diagnosis

Anthropic: Claude Opus 4.5 | model capability unsupported

Anthropic: Claude Opus 4.5 returning 400 / model capability unsupported means you should first confirm whether model ID anthropic/claude-opus-4.5 is visible for this Anthropic key, then separate permission, context, capability, rate limit, or route issues.

Model
anthropic/claude-opus-4.5
Anthropic: Claude Opus 4.5
Provider
Anthropic
13 models in catalog
Error type
model capability unsupported
capability-unsupported
Status code
400
global model route
Model error summary
Model
anthropic/claude-opus-4.5
Error type
capability-unsupported
Status code
400
Read-only check. Detection data burns after 5 minutes.
Read-only check. Detection data burns after 5 minutes.

What this model error usually means

Anthropic: Claude Opus 4.5 returning 400 / model capability unsupported means you should first confirm whether model ID anthropic/claude-opus-4.5 is visible for this Anthropic key, then separate permission, context, capability, rate limit, or route issues.

  • Model: anthropic/claude-opus-4.5
  • Provider: Anthropic
  • Status code: 400

How to prove it during checking

Read-only check. Detection data burns after 5 minutes.

  • List models: confirm whether anthropic/claude-opus-4.5 is actually visible instead of guessing from the display name.
  • Light probe: use minimal input to verify whether Anthropic returns the same 400, then record the error body.
  • Compare model facts: context 200,000, input $5, output $25.
  • supports include_reasoning
  • supports max_tokens
  • supports reasoning
  • supports response_format

Next action

Anthropic: Claude Opus 4.5 model capability unsupported should not end at failed. Return the next move: change model ID, add permission, reduce context, disable unsupported capability, change route, monitor, or hold listing.

  • Context: 200,000
  • Price: $5 / $25
  • Read-only check. Detection data burns after 5 minutes.