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+# Harness Interface Specification
+
+## Standard Interface (All Harnesses Must Implement)
+
+```python
+class Harness(ABC):
+    '''Abstract base for all agent harnesses'''
+    
+    @abstractmethod
+    def execute(self, prompt: str, context: Context) -> Response:
+        '''Execute a prompt and return response'''
+        pass
+    
+    @abstractmethod
+    def tool_call(self, tool: str, params: dict) -> Result:
+        '''Execute a specific tool'''
+        pass
+    
+    @abstractmethod
+    def session_save(self, session: Session) -> Checkpoint:
+        '''Save session state'''
+        pass
+    
+    @abstractmethod
+    def session_load(self, checkpoint: Checkpoint) -> Session:
+        '''Load session state'''
+        pass
+    
+    @property
+    @abstractmethod
+    def capabilities(self) -> List[str]:
+        '''Return list of supported capabilities'''
+        pass
+    
+    @property
+    @abstractmethod
+    def metrics(self) -> Metrics:
+        '''Return performance metrics'''
+        pass
+
+class ClawHarness(Harness):
+    '''Claw Code implementation'''
+    
+    def __init__(self, binary_path: str, model: str):
+        self.binary = binary_path
+        self.model = model
+        self.bridge = OllamaBridge()  # or direct
+    
+    def execute(self, prompt, context):
+        # Claw-specific: fast, local, tool-heavy
+        return self.bridge.run(prompt, model=self.model)
+
+class HermesHarness(Harness):
+    '''Hermes Agent implementation'''
+    
+    def __init__(self, profile: str):
+        self.profile = profile
+        self.gateway = GatewayClient()
+    
+    def execute(self, prompt, context):
+        # Hermes-specific: complex workflows, skills
+        return self.gateway.chat(prompt, profile=self.profile)
+
+class OllamaHarness(Harness):
+    '''Ollama local implementation'''
+    
+    def __init__(self, model: str = "qwen2.5:1.5b"):
+        self.model = model
+        self.client = OllamaClient()
+    
+    def execute(self, prompt, context):
+        # Ollama-specific: fully local, offline
+        return self.client.generate(prompt, model=self.model)
+```
+
+## Usage (Wizard Code)
+
+```python
+# Config-driven harness selection
+config = load_profile("allegro")
+harness = HarnessFactory.create(config.harness.default)
+
+# Same code, different runtime
+response = harness.execute("Write Python hello world", context)
+
+# Fallback chain
+for harness_name in config.harness.fallbacks:
+    try:
+        harness = HarnessFactory.create(harness_name)
+        return harness.execute(prompt, context)
+    except HarnessError:
+        continue
+```
+
+## Configuration Schema
+
+```yaml
+# ~/.hermes/profiles/allegro/config.yaml
+harness:
+  default: claw
+  fallbacks:
+    - name: hermes
+      condition: "complex_workflow"
+    - name: ollama
+      condition: "offline"
+  
+  claw:
+    binary: /opt/claw/claw-cli
+    model: claude-3-7-sonnet
+    bridge: ollama  # or direct
+  
+  hermes:
+    profile: allegro
+    gateway: http://localhost:8644
+  
+  ollama:
+    model: qwen2.5:1.5b
+    host: http://localhost:11434
+
+tools:
+  - file
+  - terminal
+  - web
+
+selection_criteria:
+  speed: claw > ollama > hermes
+  capability: hermes > claw > ollama
+  offline: ollama only
+```
+
+---
+
+*Design by Ezra*  
+*Implementation by Allegro*
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