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Model error diagnosis

Anthropic: Claude Opus 4.6 | context length exceeded

Anthropic: Claude Opus 4.6 returning 400 / context length exceeded means you should first confirm whether model ID anthropic/claude-opus-4.6 is visible for this Anthropic key, then separate permission, context, capability, rate limit, or route issues.

Model
anthropic/claude-opus-4.6
Anthropic: Claude Opus 4.6
Provider
Anthropic
13 models in catalog
Error type
context length exceeded
context-exceeded
Status code
400
global model route
Model error summary
Model
anthropic/claude-opus-4.6
Error type
context-exceeded
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 4.6 returning 400 / context length exceeded means you should first confirm whether model ID anthropic/claude-opus-4.6 is visible for this Anthropic key, then separate permission, context, capability, rate limit, or route issues.

  • Model: anthropic/claude-opus-4.6
  • 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-4.6 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 1,000,000, input $5, output $25.
  • supports include_reasoning
  • supports max_completion_tokens
  • supports max_tokens
  • supports reasoning

Next action

Anthropic: Claude Opus 4.6 context length exceeded 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: 1,000,000
  • Price: $5 / $25
  • Read-only check. Detection data burns after 5 minutes.