Feature Request

Add native support for Anthropic Claude Opus 4.5 via Google Vertex AI Model Garden.

Context

OpenClaw currently supports:

• anthropic (Direct API)
• google-vertex (Gemini models)

Enterprise users often require Claude via Vertex AI for compliance, data residency, and IAM/ADC authentication benefits.

Requirements

1. Extend google-vertex provider or add anthropic-vertex.
2. Support Google ADC (Application Default Credentials) for auth.
3. Map standard Anthropic messages API to the Vertex AI prediction endpoint format for Claude models.

Proposed Config

"agents": {
  "defaults": {
    "model": { "primary": "google-vertex/claude-opus-4-5" }
  }
}