diff --git a/server-rs/crates/shared-contracts/src/editor_agent.rs b/server-rs/crates/shared-contracts/src/editor_agent.rs
index ffa18e562..da29519d1 100644
--- a/server-rs/crates/shared-contracts/src/editor_agent.rs
+++ b/server-rs/crates/shared-contracts/src/editor_agent.rs
@@ -1,7 +1,7 @@
 //! 画布Agent对话契约：与 packages/shared/src/contracts/editorAgent.ts 保持同形。
 //! 会话元数据存 SpacetimeDB，消息正文整体存 OSS（editor-agent/{conversationId}.json）。
 
-use serde::{Deserialize, Serialize};
+use serde::{Deserialize, Deserializer, Serialize};
 
 pub const EDITOR_AGENT_MAX_ATTACHMENTS: usize = 9;
 pub const EDITOR_AGENT_TITLE_MAX_CHARS: usize = 20;
@@ -155,10 +155,29 @@ pub struct EditorAgentToolCall {
     #[serde(default)]
     pub error: Option<String>,
 }
+fn deserialize_id_or_zero<'de, D>(deserializer: D) -> Result<usize, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum IdOrZero {
+        Num(usize),
+        Str(String),
+        Other(serde_json::Value),
+    }
+
+    match IdOrZero::deserialize(deserializer)? {
+        IdOrZero::Num(n) => Ok(n),
+        _ => Ok(0),
+    }
+}
 
 #[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
 #[serde(rename_all = "camelCase")]
 pub struct EditorAgentMessage {
+    // to compatible for legacy version
+    #[serde(deserialize_with = "deserialize_id_or_zero")]
     pub id: usize,
     pub role: EditorAgentMessageRole,
     pub text: String,