diff --git a/apps/ai-game-creator-shell/src-tauri/src/agent/claude_code_cli.rs b/apps/ai-game-creator-shell/src-tauri/src/agent/claude_code_cli.rs
index a6ad51e1f..1b56483b5 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/agent/claude_code_cli.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/agent/claude_code_cli.rs
@@ -385,12 +385,44 @@ fn configure_claude_code_environment(
         {
             command.env("ANTHROPIC_AUTH_TOKEN", llm.api_key.trim());
         }
+        // Official AGC model entries use the account session rather than a
+        // user-supplied API key.  The Claude SDK only reads Anthropic auth
+        // from its child-process environment, so bridge the already-held
+        // platform token without persisting or exposing it in argv/logs.
+        if llm.api_key.trim().is_empty()
+            && !llm.custom_enabled
+            && std::env::var_os("ANTHROPIC_API_KEY").is_none()
+            && std::env::var_os("ANTHROPIC_AUTH_TOKEN").is_none()
+        {
+            if let Some(session) = crate::platform_session::current_platform_session() {
+                command.env("ANTHROPIC_AUTH_TOKEN", session.access_token);
+            }
+        }
         if !llm.model.trim().is_empty() {
             command.env("ANTHROPIC_MODEL", llm.model.trim());
         }
     }
 }
 
+fn claude_result_error_detail(value: &serde_json::Value) -> Option<String> {
+    let candidates = [
+        value.get("result").and_then(serde_json::Value::as_str),
+        value.get("error").and_then(serde_json::Value::as_str),
+        value.get("message").and_then(serde_json::Value::as_str),
+        value
+            .get("errors")
+            .and_then(serde_json::Value::as_array)
+            .and_then(|errors| errors.first())
+            .and_then(serde_json::Value::as_str),
+    ];
+    candidates
+        .into_iter()
+        .flatten()
+        .map(str::trim)
+        .find(|detail| !detail.is_empty())
+        .map(|detail| detail.chars().take(512).collect())
+}
+
 fn configure_claude_code_process(command: &mut tokio::process::Command) {
     super::codex_cli::configure_game_creator_codex_cli_process(command);
 }
@@ -495,9 +527,12 @@ fn parse_claude_code_result(
         platform_llm::LlmError::Deserialize("Claude Code JSON 输出无效".to_string())
     })?;
     if value.get("is_error").and_then(serde_json::Value::as_bool) == Some(true) {
-        return Err(platform_llm::LlmError::Transport(
-            "Claude Code 返回失败终态".to_string(),
-        ));
+        let detail = claude_result_error_detail(&value)
+            .map(|detail| format!("：{detail}"))
+            .unwrap_or_default();
+        return Err(platform_llm::LlmError::Transport(format!(
+            "Claude Code 返回失败终态{detail}"
+        )));
     }
     let response_id = value
         .get("session_id")
@@ -829,7 +864,10 @@ fn parse_direct_stream_result(
             }
         } else if event_type == Some("result") {
             if event.get("is_error").and_then(serde_json::Value::as_bool) == Some(true) {
-                return Err("Claude Code 返回失败终态".to_string());
+                let detail = claude_result_error_detail(&event)
+                    .map(|detail| format!("：{detail}"))
+                    .unwrap_or_default();
+                return Err(format!("Claude Code 返回失败终态{detail}"));
             }
             result = event
                 .get("result")
@@ -884,6 +922,16 @@ mod tests {
         assert_eq!(response.tool_calls[0].name, "runtime_tool_file_read");
     }
 
+    #[test]
+    fn preserves_claude_terminal_error_detail() {
+        let error = parse_claude_code_result(
+            br#"{"is_error":true,"result":"Authentication failed"}"#,
+            &request(false),
+        )
+        .expect_err("failed terminal must be rejected");
+        assert!(error.to_string().contains("Authentication failed"));
+    }
+
     #[test]
     fn parses_direct_stream_result_and_final_text() {
         let mut observed = Vec::new();
@@ -903,4 +951,16 @@ mod tests {
             [DirectCodexTurnObservation::AgentMessageSegment { .. }]
         ));
     }
+
+    #[test]
+    fn preserves_direct_stream_terminal_error_detail() {
+        let error = parse_direct_stream_result(
+            br#"{"type":"result","is_error":true,"result":"Authentication failed"}
+"#,
+            "turn-1",
+            None,
+        )
+        .expect_err("failed terminal must be rejected");
+        assert!(error.contains("Authentication failed"));
+    }
 }
diff --git a/docs/project-memory/shared-memory/pitfalls.md b/docs/project-memory/shared-memory/pitfalls.md
index 5c093965c..3528c71a9 100644
--- a/docs/project-memory/shared-memory/pitfalls.md
+++ b/docs/project-memory/shared-memory/pitfalls.md
@@ -6158,3 +6158,9 @@ Cocos Creator 根目录由 `package.json.creator.version` 与普通 `assets/` 
 - **同时**：主站顶栏（`platform-desktop-topbar`）在窄屏必须保持单行——加 `flex-wrap` 后新增一个动作入口就会让品牌折到第二行；窄屏降级靠 `< 640px` 图标化下载入口、`< 480px` 只留品牌 IP 标识。
 - **验证**：真机尺寸下用 `document.elementFromPoint(按钮中心)` 断言命中的是按钮自身而不是底部菜单（`overlay.parentElement === document.body`）；顶栏断点矩阵（320–768）断言单行且无横向溢出。
 - **关联**：`src/components/common/SquareImageCropModal.tsx`、`src/components/platform-entry/PlatformProfileModalShell.tsx`、`src/components/platform-entry/PlatformEntryActiveFlowShell.tsx`、`src/index.css`。
+
+## 2026-10-01 AGC 官方 Claude 模型缺少账号令牌会被误报为通道断开
+
+- **现象**：模型目录把回合路由到 `cc`，本地 `game-creator.config.json` 的 `llm.apiKey` 为空时，Claude Agent SDK 返回失败终态；界面只显示“执行通道未能建立或已断开”。
+- **根因**：Claude sidecar 只从 `ANTHROPIC_API_KEY` / `ANTHROPIC_AUTH_TOKEN` 或本地 `llm.apiKey` 读取认证，没有复用已登录的 AGC 平台会话；同时失败终态解析丢弃了上游错误摘要。
+- **处理**：官方模型且未启用自定义目录时，将当前平台会话令牌仅注入 sidecar 子进程环境；保留最多 512 字符的 Claude 终态错误摘要，继续由统一诊断层脱敏，避免凭据落盘。