@@ -45,7 +45,7 @@ class AnthropicThinkingConfig(BaseModel):
 
 class AnthropicOutputConfig(BaseModel):
     """Used with `thinking.type='adaptive'` on models like Opus 4.7."""
-    effort: Literal["low", "medium", "high"] | None = Field(None)
+    effort: Literal["low", "medium", "high", "xhigh", "max"] | None = Field(None)
 
 
 class AnthropicMessagesRequest(BaseModel):
 
@@ -30,6 +30,7 @@
 CLAUDE_MODELS: dict[str, str] = {
     "Opus 5": "claude-opus-5",
     "Opus 4.8": "claude-opus-4-8",
+    "Fable 5.1": "claude-fable-5-1",
     "Fable 5": "claude-fable-5",
     "Sonnet 5": "claude-sonnet-5",
     "Opus 4.7": "claude-opus-4-7",
@@ -43,9 +44,11 @@
 # Models that use the newer "adaptive" thinking mode (Opus 4.7+ require it; older models keep the explicit budget API).
 # Anthropic decides the actual budget when adaptive is used, based on the `output_config.effort` hint.
 _ADAPTIVE_THINKING_MODELS = {"Opus 4.8", "Sonnet 5", "Opus 4.7", "Opus 4.6", "Sonnet 4.6"}
-_ALWAYS_THINKING_MODELS = {"Opus 5", "Fable 5"}
+_ALWAYS_THINKING_MODELS = {"Opus 5", "Fable 5.1", "Fable 5"}
+_XHIGH_EFFORT_MODELS = {"Opus 5", "Opus 4.8", "Fable 5.1", "Fable 5", "Sonnet 5", "Opus 4.7"}
+_MAX_EFFORT_MODELS = _XHIGH_EFFORT_MODELS | {"Opus 4.6", "Sonnet 4.6"}
 _EXPLICIT_THINKING_OFF_MODELS = {"Sonnet 5"}
-_NO_TEMPERATURE_MODELS = {"Opus 5", "Opus 4.8", "Fable 5", "Sonnet 5"}
+_NO_TEMPERATURE_MODELS = {"Opus 5", "Opus 4.8", "Fable 5.1", "Fable 5", "Sonnet 5"}
 
 # Budget mode (Sonnet 4.5): effort -> reasoning budget in tokens. Must be < max_tokens.
 # Sized so even the "high" budget fits comfortably under the default max_tokens=32768.
@@ -57,6 +60,17 @@
 _REASONING_EFFORTS = ["off", "low", "medium", "high"]
 
 
+def _reasoning_effort_options(model_label: str) -> list[str]:
+    options = list(_REASONING_EFFORTS)
+    if model_label in _ALWAYS_THINKING_MODELS:
+        options.remove("off")
+    if model_label in _XHIGH_EFFORT_MODELS:
+        options.append("xhigh")
+    if model_label in _MAX_EFFORT_MODELS:
+        options.append("max")
+    return options
+
+
 def _claude_model_inputs(model_label: str):
     inputs: list = [
         IO.Int.Input(
@@ -87,7 +101,7 @@ def _claude_model_inputs(model_label: str):
         inputs.append(
             IO.Combo.Input(
                 "reasoning_effort",
-                options=[e for e in _REASONING_EFFORTS if e != "off"],
+                options=_reasoning_effort_options(model_label),
                 default="high",
                 tooltip="Extended thinking effort. Reasoning is always enabled for this model.",
                 advanced=True,
@@ -97,7 +111,7 @@ def _claude_model_inputs(model_label: str):
         inputs.append(
             IO.Combo.Input(
                 "reasoning_effort",
-                options=_REASONING_EFFORTS,
+                options=_reasoning_effort_options(model_label),
                 default="off",
                 tooltip="Extended thinking effort. 'off' disables reasoning.",
                 advanced=True,