Phase 5: AI/MCP Bearer-Auth + Delegationstoken + Audit

5.1 Delegationstoken (app/core/delegation_token.py):
- HMAC-SHA256 signiert mit SECRET_KEY, max 60s Lifetime
- Payload: user_id, tenant_id, agent_id, audience, expires_at, token_id
- Statelose Verifikation, Audience-Check, Expiry-Check

5.2 MCP Bearer-Auth:
- app/core/api_token.py: Token Service (create, verify, revoke, list)
- app/deps.py: get_current_user_bearer + get_current_user_or_bearer
- app/routes/api_tokens.py: Token CRUD Routes (create, list, revoke)
- MCP Server Routes: get_current_user_or_bearer akzeptiert Session + Bearer

5.3 Methodenrechte:
- MCP nutzt bereits mcp:read/mcp:write basierend auf tool_def.required_permission

5.5 Audit:
- MCP Tool-Ausfuehrung wird protokolliert (log_audit mit correlation_id)

Tests: 13/13 bestanden (7 API Token + 6 Delegation Token)

app/plugins/builtins/mcp_server/routes.py

@@ -10,7 +10,7 @@ from fastapi import APIRouter, Depends, Header, HTTPException, status
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.db import get_db
-from app.deps import get_current_user, require_permission
+from app.deps import get_current_user, get_current_user_or_bearer, require_permission
 from app.plugins.builtins.mcp_server.schemas import (
     McpServerConfig,
     McpToolDefinition,
@@ -58,10 +58,11 @@ async def execute_mcp_tool(
     tool_name: str,
     request: McpToolExecuteRequest,
     db: AsyncSession = Depends(get_db),
-    current_user: dict[str, Any] = Depends(get_current_user),
+    current_user: dict[str, Any] = Depends(get_current_user_or_bearer),
 ) -> McpToolExecuteResponse:
     """Execute an MCP tool by name with provided arguments.
 
+    Accepts session cookie OR Bearer token (for programmatic access).
     Requires mcp:read for read tools, mcp:write for write tools.
     """
     tool_def = get_tool_definition(tool_name)
@@ -93,8 +94,23 @@ async def execute_mcp_tool(
         "user_id": current_user.get("user_id"),
         "role": current_user.get("role"),
         "permissions": current_user.get("permissions", []),
+        "auth_method": current_user.get("_auth_method", "session"),
     }
 
+    # Audit log
+    from app.core.audit import log_audit
+    import uuid as uuid_mod
+    correlation_id = str(uuid_mod.uuid4())
+    await log_audit(
+        db,
+        tenant_id=uuid.UUID(current_user["tenant_id"]),
+        user_id=uuid.UUID(current_user["user_id"]),
+        action="mcp.tool.execute",
+        entity_type="mcp_tool",
+        entity_id=tool_name,
+        details={"tool": tool_name, "arguments": request.arguments, "correlation_id": correlation_id, "auth_method": context["auth_method"]},
+    )
+
     try:
         result = await handler(db, request.arguments, context)
         await db.commit()