fix(anthropic): live model fetching + adaptive thinking for 4.5+ models

- Add _fetch_anthropic_models() to hermes_cli/models.py — hits the
  Anthropic /v1/models endpoint to get the live model catalog. Handles
  both API key and OAuth token auth headers.

- Wire it into provider_model_ids() so both 'hermes model' and
  'hermes setup model' show the live list instead of a stale static one.

- Update static _PROVIDER_MODELS fallback with full current catalog:
  opus-4-6, sonnet-4-6, opus-4-5, sonnet-4-5, opus-4, sonnet-4, haiku-4-5

- Update model_metadata.py with context lengths for all current models.

- Fix thinking parameter for 4.5+ models: use type='adaptive' instead
  of type='enabled' (Anthropic deprecated 'enabled' for newer models,
  warns at runtime). Detects model version from the model name string.

Verified live:
  hermes model → Anthropic → auto-detected creds → shows 7 live models
  hermes chat --provider anthropic --model claude-opus-4-6 → works

agent/anthropic_adapter.py

@@ -363,11 +363,16 @@ def build_anthropic_kwargs(
             kwargs["tool_choice"] = {"type": "tool", "name": tool_choice}
 
     # Map reasoning_config to Anthropic's thinking parameter
+    # Newer models (4.6+) prefer "adaptive" thinking; older models use "enabled"
     if reasoning_config and isinstance(reasoning_config, dict):
         if reasoning_config.get("enabled") is not False:
             effort = reasoning_config.get("effort", "medium")
             budget = THINKING_BUDGET.get(effort, 8000)
-            kwargs["thinking"] = {"type": "enabled", "budget_tokens": budget}
+            # Use adaptive thinking for 4.5+ models (they deprecate type=enabled)
+            if any(v in model for v in ("4-6", "4-5", "4.6", "4.5")):
+                kwargs["thinking"] = {"type": "adaptive", "budget_tokens": budget}
+            else:
+                kwargs["thinking"] = {"type": "enabled", "budget_tokens": budget}
             kwargs["max_tokens"] = max(effective_max_tokens, budget + 4096)
 
     return kwargs

agent/model_metadata.py

@@ -42,6 +42,11 @@ DEFAULT_CONTEXT_LENGTHS = {
     "anthropic/claude-sonnet-4-20250514": 200000,
     "anthropic/claude-haiku-4.5": 200000,
     # Bare Anthropic model IDs (for native API provider)
+    "claude-opus-4-6": 200000,
+    "claude-sonnet-4-6": 200000,
+    "claude-opus-4-5-20251101": 200000,
+    "claude-sonnet-4-5-20250929": 200000,
+    "claude-opus-4-1-20250805": 200000,
     "claude-opus-4-20250514": 200000,
     "claude-sonnet-4-20250514": 200000,
     "claude-haiku-4-5-20251001": 200000,

hermes_cli/models.py

@@ -69,8 +69,12 @@ _PROVIDER_MODELS: dict[str, list[str]] = {
         "MiniMax-M2.1",
     ],
     "anthropic": [
-        "claude-sonnet-4-20250514",
+        "claude-opus-4-6",
+        "claude-sonnet-4-6",
+        "claude-opus-4-5-20251101",
+        "claude-sonnet-4-5-20250929",
         "claude-opus-4-20250514",
+        "claude-sonnet-4-20250514",
         "claude-haiku-4-5-20251001",
     ],
 }
@@ -242,9 +246,54 @@ def provider_model_ids(provider: Optional[str]) -> list[str]:
                     return live
         except Exception:
             pass
+    if normalized == "anthropic":
+        live = _fetch_anthropic_models()
+        if live:
+            return live
     return list(_PROVIDER_MODELS.get(normalized, []))
 
 
+def _fetch_anthropic_models(timeout: float = 5.0) -> Optional[list[str]]:
+    """Fetch available models from the Anthropic /v1/models endpoint.
+
+    Uses resolve_anthropic_token() to find credentials (env vars or
+    Claude Code auto-discovery).  Returns sorted model IDs or None.
+    """
+    try:
+        from agent.anthropic_adapter import resolve_anthropic_token, _is_oauth_token
+    except ImportError:
+        return None
+
+    token = resolve_anthropic_token()
+    if not token:
+        return None
+
+    headers: dict[str, str] = {"anthropic-version": "2023-06-01"}
+    if _is_oauth_token(token):
+        headers["Authorization"] = f"Bearer {token}"
+        headers["anthropic-beta"] = "oauth-2025-04-20"
+    else:
+        headers["x-api-key"] = token
+
+    req = urllib.request.Request(
+        "https://api.anthropic.com/v1/models",
+        headers=headers,
+    )
+    try:
+        with urllib.request.urlopen(req, timeout=timeout) as resp:
+            data = json.loads(resp.read().decode())
+            models = [m["id"] for m in data.get("data", []) if m.get("id")]
+            # Sort: latest/largest first (opus > sonnet > haiku, higher version first)
+            return sorted(models, key=lambda m: (
+                "opus" not in m,      # opus first
+                "sonnet" not in m,    # then sonnet
+                "haiku" not in m,     # then haiku
+                m,                    # alphabetical within tier
+            ))
+    except Exception:
+        return None
+
+
 def fetch_api_models(
     api_key: Optional[str],
     base_url: Optional[str],

hermes_cli/setup.py

@@ -1229,9 +1229,12 @@ def setup_model_provider(config: dict):
                     _set_default_model(config, custom)
             # else: keep current
         elif selected_provider == "anthropic":
-            anthropic_models = [
-                "claude-sonnet-4-20250514",
-                "claude-opus-4-20250514",
+            # Try live model list first, fall back to static
+            from hermes_cli.models import provider_model_ids
+            live_models = provider_model_ids("anthropic")
+            anthropic_models = live_models if live_models else [
+                "claude-opus-4-6",
+                "claude-sonnet-4-6",
                 "claude-haiku-4-5-20251001",
             ]
             model_choices = list(anthropic_models)