feat: enhance subagent context with abort flag and implement tool call timeout

src/app/subagent/engine.rs

@@ -18,6 +18,10 @@ use super::event::SubagentEvent;
 #[allow(dead_code)]
 pub const MAX_AGENT_STEPS: usize = usize::MAX;
 
+/// Maximum time a single tool call may block inside a subagent before
+/// being abandoned. Prevents a stuck tool from hanging the subagent loop.
+const SUBAGENT_TOOL_TIMEOUT_MS: u64 = 120_000;
+
 /// Maps a subagent's allowed tool names to concrete Tool trait objects and
 /// OpenAI-style tool definitions.
 ///
@@ -328,6 +332,16 @@ pub fn run_subagent(ctx: SubagentContext, tx: mpsc::Sender<SubagentEvent>) -> an
 
     for step in 0..ctx.max_steps {
 
+        // Check abort flag before each LLM call so a stuck subagent can
+        // be cancelled from the parent (mirrors main agent behaviour).
+        if ctx.abort_flag.as_ref().is_some_and(|f| f.load(std::sync::atomic::Ordering::SeqCst)) {
+            let _ = tx.blocking_send(SubagentEvent::StepFailed {
+                _step: step,
+                _error: "subagent aborted by parent".to_string(),
+            });
+            anyhow::bail!("subagent aborted by parent at step {}", step);
+        }
+
         // Use the structured tool-calling API so the LLM can request tools with
         // proper arguments, exactly like the main agent does.
         let (response, _usage) = match client.chat_with_tools_non_streaming(&messages, tdefs_opt.clone()) {
@@ -352,6 +366,15 @@ pub fn run_subagent(ctx: SubagentContext, tx: mpsc::Sender<SubagentEvent>) -> an
             messages.push(response);
 
             for tool_call in &tool_calls {
+                // Check abort flag before each tool execution
+                if ctx.abort_flag.as_ref().is_some_and(|f| f.load(std::sync::atomic::Ordering::SeqCst)) {
+                    let _ = tx.blocking_send(SubagentEvent::StepFailed {
+                        _step: step,
+                        _error: "subagent aborted by parent during tool execution".to_string(),
+                    });
+                    anyhow::bail!("subagent aborted by parent during tool call at step {}", step);
+                }
+
                 let tool_name = &tool_call.function.name;
                 let args = crate::dto::chat::tool::sanitize_tool_arguments(&tool_call.function.arguments);
                 let explicitly_allowed = ctx.allowed_tools.contains(tool_name);