diff --git a/src/channels/mod.rs b/src/channels/mod.rs
index 435deb7..127e2f5 100644
--- a/src/channels/mod.rs
+++ b/src/channels/mod.rs
@@ -626,14 +626,14 @@ async fn process_channel_message(ctx: Arc<ChannelRuntimeContext>, msg: traits::C
         .cloned()
         .unwrap_or_default();
 
-    let mut history = vec![ChatMessage::system(ctx.system_prompt.as_str())];
+    let system_prompt = match channel_delivery_instructions(&msg.channel) {
+        Some(instructions) => format!("{}\n\n{instructions}", ctx.system_prompt),
+        None => ctx.system_prompt.to_string(),
+    };
+    let mut history = vec![ChatMessage::system(&system_prompt)];
     history.append(&mut prior_turns);
     history.push(ChatMessage::user(&enriched_message));
 
-    if let Some(instructions) = channel_delivery_instructions(&msg.channel) {
-        history.push(ChatMessage::system(instructions));
-    }
-
     // Determine if this channel supports streaming draft updates
     let use_streaming = target_channel
         .as_ref()
@@ -2304,6 +2304,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2356,6 +2357,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2417,6 +2419,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2499,6 +2502,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2557,6 +2561,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2610,6 +2615,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -2714,6 +2720,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         let (tx, rx) = tokio::sync::mpsc::channel::<traits::ChannelMessage>(4);
@@ -2784,6 +2791,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(
@@ -3174,6 +3182,7 @@ mod tests {
             reliability: Arc::new(crate::config::ReliabilityConfig::default()),
             provider_runtime_options: providers::ProviderRuntimeOptions::default(),
             workspace_dir: Arc::new(std::env::temp_dir()),
+            channel_message_timeout_secs: 300,
         });
 
         process_channel_message(