chore: mini-openclaw 初始版本

Next.js 前端 + FastAPI/LangChain 后端透明 agent平台
- 含 .gitignore, 敏感文件(sessions数据/.env/venv等)已排除
- 待后续添加 trajectory 自进化机制

backend/api/tokens.py

@@ -0,0 +1,68 @@
+"""GET/POST /api/tokens — Token counting for sessions and files."""
+
+from pathlib import Path
+from typing import Any
+
+import tiktoken
+from fastapi import APIRouter, HTTPException
+from pydantic import BaseModel
+
+from graph.session_manager import session_manager
+from graph.prompt_builder import build_system_prompt
+
+router = APIRouter()
+
+BASE_DIR = Path(__file__).resolve().parent.parent
+
+# Cache the encoder instance
+_encoder = tiktoken.get_encoding("cl100k_base")
+
+
+def _count_tokens(text: str) -> int:
+    """Count tokens using cl100k_base encoding."""
+    return len(_encoder.encode(text))
+
+
+@router.get("/tokens/session/{session_id}")
+async def get_session_token_count(session_id: str) -> dict[str, Any]:
+    """Count tokens in a session: system prompt + all messages."""
+    system_prompt = build_system_prompt(BASE_DIR)
+    system_tokens = _count_tokens(system_prompt)
+
+    messages = session_manager.load_session(session_id)
+    message_tokens = 0
+    for msg in messages:
+        message_tokens += _count_tokens(msg.get("content", ""))
+
+    return {
+        "system_tokens": system_tokens,
+        "message_tokens": message_tokens,
+        "total_tokens": system_tokens + message_tokens,
+    }
+
+
+class FileTokenRequest(BaseModel):
+    paths: list[str]
+
+
+@router.post("/tokens/files")
+async def get_file_token_counts(request: FileTokenRequest) -> dict[str, Any]:
+    """Count tokens for a list of files."""
+    results: list[dict[str, Any]] = []
+    for rel_path in request.paths:
+        normalized = rel_path.replace("\\", "/").lstrip("./")
+        full_path = (BASE_DIR / normalized).resolve()
+        if not str(full_path).startswith(str(BASE_DIR)):
+            results.append({"path": rel_path, "tokens": 0})
+            continue
+        if not full_path.exists():
+            results.append({"path": rel_path, "tokens": 0})
+            continue
+        try:
+            content = full_path.read_text(encoding="utf-8")
+            tokens = _count_tokens(content)
+            results.append({"path": rel_path, "tokens": tokens})
+        except Exception:
+            results.append({"path": rel_path, "tokens": 0})
+
+    return {"files": results}