代码修改

offline-backend-20260512/backend/app/gateway/services.py

@@ -152,10 +152,12 @@ _CONTEXT_CONFIGURABLE_KEYS: frozenset[str] = frozenset(
         "model_name",
         "mode",
         "thinking_enabled",
-        "reasoning_effort",
-        "writing_mode",
-        "writing_artifact_path",
-        "is_plan_mode",
+        "reasoning_effort",
+        "writing_mode",
+        "writing_artifact_path",
+        "canvas_artifact_title",
+        "canvas_artifact_type",
+        "is_plan_mode",
         "subagent_enabled",
         "max_concurrent_subagents",
         "agent_name",

offline-backend-20260512/backend/packages/harness/deerflow/agents/canvas_agent/agent.py

@@ -5,7 +5,7 @@ import logging
 from langchain.agents import create_agent
 from langchain_core.runnables import RunnableConfig
 
-from deerflow.agents.canvas_agent.prompt import CANVAS_SYSTEM_PROMPT
+from deerflow.agents.canvas_agent.prompt import build_canvas_system_prompt
 from deerflow.agents.canvas_agent.tools import update_artifact_tool
 from deerflow.agents.middlewares.clarification_middleware import ClarificationMiddleware
 from deerflow.agents.middlewares.dangling_tool_call_middleware import DanglingToolCallMiddleware
@@ -49,7 +49,19 @@ def make_canvas_agent(config: RunnableConfig):
     if thinking_enabled and model_config and not model_config.supports_thinking:
         thinking_enabled = False
 
-    logger.info("Create CanvasAgent -> model_name: %s, thinking_enabled: %s", model_name, thinking_enabled)
+    canvas_artifact_title = cfg.get("canvas_artifact_title") or None
+    canvas_artifact_type = cfg.get("canvas_artifact_type") or None
+    system_prompt = build_canvas_system_prompt(
+        artifact_title=canvas_artifact_title,
+        artifact_type=canvas_artifact_type,
+    )
+
+    logger.info(
+        "Create CanvasAgent -> model_name: %s, thinking_enabled: %s, artifact_title: %s",
+        model_name,
+        thinking_enabled,
+        canvas_artifact_title,
+    )
 
     middlewares = [
         DanglingToolCallMiddleware(),
@@ -63,6 +75,6 @@ def make_canvas_agent(config: RunnableConfig):
         model=create_chat_model(name=model_name, thinking_enabled=thinking_enabled, app_config=app_config),
         tools=[update_artifact_tool, ask_clarification_tool],
         middleware=middlewares,
-        system_prompt=CANVAS_SYSTEM_PROMPT,
+        system_prompt=system_prompt,
         state_schema=ThreadState,
     )

offline-backend-20260512/backend/packages/harness/deerflow/agents/canvas_agent/prompt.py

@@ -1,4 +1,18 @@
-CANVAS_SYSTEM_PROMPT = """You are a Canvas AI assistant that helps users create and edit documents and code.
+def build_canvas_system_prompt(
+    artifact_title: str | None = None,
+    artifact_type: str | None = None,
+) -> str:
+    existing_artifact_block = ""
+    if artifact_title:
+        type_label = "代码" if artifact_type == "code" else "文档"
+        existing_artifact_block = f"""
+<existing_artifact>
+用户当前有一个{type_label}制品，标题为 "{artifact_title}"。
+请继续编辑该制品——除非用户明确要求新建，否则不要创建新制品。
+</existing_artifact>
+"""
+
+    return f"""You are a Canvas AI assistant that helps users create and edit documents and code.
 
 <canvas_behavior>
 You work with an **artifact** — a document or code file shown in the canvas panel on the right.
@@ -14,7 +28,7 @@ Rules:
 The current artifact state is injected into your context. When editing, build on the existing content exactly.
 When creating from scratch, produce a complete, high-quality artifact in one shot.
 </artifact_context>
-
+{existing_artifact_block}
 <selection_rewrite>
 When the user's message contains a <selection> block, you MUST:
 1. Identify the exact selection in the current artifact content.
@@ -38,3 +52,7 @@ When the user triggers a quick action, apply it to the full artifact unless spec
 - optimize_code: Improve performance and readability
 </quick_actions>
 """
+
+
+# Backward-compatible constant for callers that don't pass artifact context.
+CANVAS_SYSTEM_PROMPT = build_canvas_system_prompt()