Environment Variables, Settings, Feature Flags, And Missing-Dependency Failure Modes

Required Versus Optional Inputs

Hard requirements for a successful model call

At least one provider and auth path must be valid:

• Anthropic first-party auth, usually OAuth state or ANTHROPIC_API_KEY.
• Bedrock auth environment plus provider selection.
• Vertex auth environment plus provider selection.
• Foundry or Azure auth environment plus provider selection.
• If none of those are available, the client can still start, but it cannot successfully send a query.

Required only in specific modes

• Remote and bridge mode: session ingress URLs and tokens plus bridge auth values such as CLAUDE_CODE_SESSION_ACCESS_TOKEN, , and .