1 files changed, 44 insertions, 0 deletions
diff --git a/agent/orchestrator/models/base.py b/agent/orchestrator/models/base.py
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+"""Backend-agnostic model interface.
+
+Concrete backends (Claude Code, Ollama, Anthropic API direct, OpenCode, etc.)
+implement `ModelBackend.call`. The orchestration code only ever talks to this
+interface, never to a specific backend.
+
+Persona is NOT carried in ModelRequest; that's a backend-level configuration
+concern (some backends autodiscover persona from a workspace, others need to
+be told). What flows through here is per-turn DYNAMIC context only.
+"""
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+from typing import Literal
+
+
+Role = Literal["system", "user", "assistant", "tool"]
+
+
+@dataclass
+class Message:
+    role: Role
+    content: str
+
+
+@dataclass
+class ModelRequest:
+    """Everything a backend needs to produce one response."""
+    messages: list[Message]
+    turn_context: str | None = None
+    extras: dict = field(default_factory=dict)
+
+
+@dataclass
+class ModelResponse:
+    """What a backend returns. Kept narrow now, extended later."""
+    content: str
+    extras: dict = field(default_factory=dict)
+
+
+class ModelBackend(ABC):
+    @abstractmethod
+    def call(self, request: ModelRequest) -> ModelResponse:
+        ...