diff --git a/PLUGIN_DEVELOPMENT.md b/PLUGIN_DEVELOPMENT.md
index 37a375c..70f563a 100644
--- a/PLUGIN_DEVELOPMENT.md
+++ b/PLUGIN_DEVELOPMENT.md
@@ -36,7 +36,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "abc-provider-NAME"
-version = "2025.09.04"  # Match abc-cli version format
+version = "2026.07.15"  # Match abc-cli version format
 description = "NAME LLM provider for abc-cli"
 readme = "README.md"
 requires-python = ">=3.8"
diff --git a/README.md b/README.md
index 15ba276..c09bdd7 100644
--- a/README.md
+++ b/README.md
@@ -328,4 +328,4 @@ Prompt crafting by Eric Hammond
 
 ## Version
 
-Current version: 2025.09.04
+Current version: 2026.07.15
diff --git a/abc_cli/abc_generate.py b/abc_cli/abc_generate.py
index 33ce255..4ab2fda 100755
--- a/abc_cli/abc_generate.py
+++ b/abc_cli/abc_generate.py
@@ -29,7 +29,7 @@
 # Entry point group for LLM providers
 PROVIDER_ENTRY_POINT = 'abc.llm_providers'
 
-VERSION: str = "abc (AI Bash Command) version 2026.04.12"
+VERSION: str = "abc (AI Bash Command) version 2026.07.15"
 PROGRAM_NAME: str = "abc"
 
 # Config file
diff --git a/abc_provider_anthropic/abc_provider_anthropic/llm_provider.py b/abc_provider_anthropic/abc_provider_anthropic/llm_provider.py
index 66e3a31..f20344c 100644
--- a/abc_provider_anthropic/abc_provider_anthropic/llm_provider.py
+++ b/abc_provider_anthropic/abc_provider_anthropic/llm_provider.py
@@ -5,8 +5,7 @@
 
 from abc_cli import LLMProvider
 
-DEFAULT_MODEL = 'claude-opus-4-5'
-DEFAULT_TEMPERATURE = 0.0
+DEFAULT_MODEL = 'claude-opus-4-8'
 DEFAULT_MAX_TOKENS = 1000
 
 class AnthropicProvider(LLMProvider):
@@ -23,7 +22,12 @@ def __init__(self, config: Dict[str, str]):
 
         self.api_key = config['api_key']
         self.model = config.get('model', DEFAULT_MODEL)
-        self.temperature = float(config.get('temperature', DEFAULT_TEMPERATURE))
+        # Newer Claude models (Opus 4.7+, Sonnet 5, Fable 5) reject the
+        # `temperature` parameter. Only send it when the user explicitly
+        # configures one; otherwise omit it entirely.
+        self.temperature = (
+            float(config['temperature']) if 'temperature' in config else None
+        )
         self.max_tokens = int(config.get('max_tokens', DEFAULT_MAX_TOKENS))
         self.client = anthropic.Anthropic(api_key=self.api_key)
 
@@ -34,12 +38,11 @@ def generate_command(
         system_prompt: str,
     ) -> str:
         """Generate command using Anthropic Claude."""
-        message = self.client.messages.create(
-            model=self.model,
-            max_tokens=self.max_tokens,
-            temperature=self.temperature,
-            system=system_prompt,
-            messages=[
+        request_params = {
+            "model": self.model,
+            "max_tokens": self.max_tokens,
+            "system": system_prompt,
+            "messages": [
                 {
                     "role": "user",
                     "content": [
@@ -50,7 +53,11 @@ def generate_command(
                     ]
                 }
             ]
-        )
+        }
+        if self.temperature is not None:
+            request_params["temperature"] = self.temperature
+
+        message = self.client.messages.create(**request_params)
         return message.content[0].text.strip()
 
     def get_config_schema(self) -> Dict:
@@ -74,8 +81,7 @@ def get_config_schema(self) -> Dict:
                 },
                 "temperature": {
                     "type": "string",
-                    "description": "Sampling temperature",
-                    "default": DEFAULT_TEMPERATURE
+                    "description": "Sampling temperature (omitted unless set; unsupported by newer Claude models)"
                 },
                 "max_tokens": {
                     "type": "string",
diff --git a/abc_provider_anthropic/pyproject.toml b/abc_provider_anthropic/pyproject.toml
index 63fa368..d09215b 100644
--- a/abc_provider_anthropic/pyproject.toml
+++ b/abc_provider_anthropic/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "abc-provider-anthropic"
-version = "2026.04.12"
+version = "2026.07.15"
 description = "Anthropic LLM provider for abc-cli"
 readme = "README.md"
 requires-python = ">=3.8"
diff --git a/abc_provider_anthropic/tests/test_provider.py b/abc_provider_anthropic/tests/test_provider.py
index e1c171f..91a71ee 100644
--- a/abc_provider_anthropic/tests/test_provider.py
+++ b/abc_provider_anthropic/tests/test_provider.py
@@ -40,7 +40,7 @@ def test_init_minimal_config():
     provider = AnthropicProvider(MOCK_CONFIG)
     assert provider.api_key == MOCK_API_KEY
     assert provider.model == DEFAULT_MODEL
-    assert provider.temperature == 0.0
+    assert provider.temperature is None
     assert provider.max_tokens == 1000
 
 def test_init_full_config():
@@ -96,6 +96,27 @@ def test_generate_command(mock_anthropic):
     assert call_kwargs["system"] == "You are a CLI assistant"
     assert len(call_kwargs["messages"]) == 1
     assert "list files" in call_kwargs["messages"][0]["content"][0]["text"]
+    # Temperature must be omitted by default — newer Claude models reject it
+    assert "temperature" not in call_kwargs
+
+@patch('anthropic.Anthropic')
+def test_generate_command_with_temperature(mock_anthropic):
+    """Test temperature is sent only when explicitly configured."""
+    mock_message = Mock()
+    mock_message.content = [Mock(text="ls -l\n##DANGERLEVEL=0## Safe command")]
+    mock_client = Mock()
+    mock_client.messages.create.return_value = mock_message
+    mock_anthropic.return_value = mock_client
+
+    provider = AnthropicProvider(MOCK_CONFIG_FULL)
+    provider.generate_command(
+        description="list files",
+        context={"shell": "bash"},
+        system_prompt="You are a CLI assistant"
+    )
+
+    call_kwargs = mock_client.messages.create.call_args.kwargs
+    assert call_kwargs["temperature"] == 0.5
 
 @patch('anthropic.Anthropic')
 def test_generate_command_api_error(mock_anthropic):
diff --git a/abc_provider_aws_bedrock/abc_provider_aws_bedrock/__init__.py b/abc_provider_aws_bedrock/abc_provider_aws_bedrock/__init__.py
index 709ccbb..9d275d6 100644
--- a/abc_provider_aws_bedrock/abc_provider_aws_bedrock/__init__.py
+++ b/abc_provider_aws_bedrock/abc_provider_aws_bedrock/__init__.py
@@ -2,4 +2,4 @@
 
 from .llm_provider import AWSBedrockProvider, PROVIDER_NAME
 
-__version__ = "2026.04.12"
+__version__ = "2026.07.15"
diff --git a/abc_provider_aws_bedrock/pyproject.toml b/abc_provider_aws_bedrock/pyproject.toml
index 78ba751..4da342b 100644
--- a/abc_provider_aws_bedrock/pyproject.toml
+++ b/abc_provider_aws_bedrock/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "abc-provider-aws-bedrock"
-version = "2026.04.12"  # Match current abc-cli version
+version = "2026.07.15"  # Match current abc-cli version
 description = "AWS Bedrock LLM provider plugin for abc-cli"
 readme = "README.md"
 requires-python = ">=3.8"
diff --git a/abc_provider_openai/abc_provider_openai/__init__.py b/abc_provider_openai/abc_provider_openai/__init__.py
index 64df117..722996a 100644
--- a/abc_provider_openai/abc_provider_openai/__init__.py
+++ b/abc_provider_openai/abc_provider_openai/__init__.py
@@ -6,4 +6,4 @@
 from .llm_provider import OpenAIProvider
 
 __all__ = ["OpenAIProvider"]
-__version__ = "2026.04.12"
\ No newline at end of file
+__version__ = "2026.07.15"
\ No newline at end of file
diff --git a/abc_provider_openai/pyproject.toml b/abc_provider_openai/pyproject.toml
index b467d0c..1d2ba78 100644
--- a/abc_provider_openai/pyproject.toml
+++ b/abc_provider_openai/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "abc-provider-openai"
-version = "2026.04.12"
+version = "2026.07.15"
 description = "OpenAI LLM provider for abc-cli"
 readme = "README.md"
 requires-python = ">=3.8"
diff --git a/flake.nix b/flake.nix
index e95e0e0..855a392 100644
--- a/flake.nix
+++ b/flake.nix
@@ -16,7 +16,7 @@
         # Build the core abc-cli package
         abc-cli = python.pkgs.buildPythonApplication rec {
           pname = "abc-cli";
-          version = "2025.09.04";
+          version = "2026.07.15";
           format = "pyproject";
 
           src = ./.;
@@ -55,7 +55,7 @@
         # Build provider packages
         abc-provider-anthropic = python.pkgs.buildPythonPackage rec {
           pname = "abc-provider-anthropic";
-          version = "2025.09.04";
+          version = "2026.07.15";
           format = "pyproject";
 
           src = ./abc_provider_anthropic;
@@ -74,7 +74,7 @@
 
         abc-provider-aws-bedrock = python.pkgs.buildPythonPackage rec {
           pname = "abc-provider-aws-bedrock";
-          version = "2025.09.04";
+          version = "2026.07.15";
           format = "pyproject";
 
           src = ./abc_provider_aws_bedrock;
diff --git a/pyproject.toml b/pyproject.toml
index 43a9409..719b1da 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "abc-cli"
-version = "2026.04.12"
+version = "2026.07.15"
 description = "AI bash/zsh/tcsh Command"
 readme = "README.md"
 requires-python = ">=3.8"