diff --git a/crates/pu-cli/src/commands/agent_def.rs b/crates/pu-cli/src/commands/agent_def.rs
index d615311..4f183b6 100644
--- a/crates/pu-cli/src/commands/agent_def.rs
+++ b/crates/pu-cli/src/commands/agent_def.rs
@@ -24,7 +24,7 @@ pub async fn run_list(socket: &Path, json: bool) -> Result<(), CliError> {
     let project_root = commands::cwd_string()?;
     let resp = client::send_request(socket, &Request::ListAgentDefs { project_root }).await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -60,7 +60,7 @@ pub async fn run_create(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -76,7 +76,7 @@ pub async fn run_show(socket: &Path, name: &str, json: bool) -> Result<(), CliEr
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -98,7 +98,7 @@ pub async fn run_delete(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
diff --git a/crates/pu-cli/src/commands/attach.rs b/crates/pu-cli/src/commands/attach.rs
index 1fddfa6..e28d552 100644
--- a/crates/pu-cli/src/commands/attach.rs
+++ b/crates/pu-cli/src/commands/attach.rs
@@ -18,6 +18,6 @@ pub async fn run(socket: &Path, agent_id: &str) -> Result<(), CliError> {
     )
     .await?;
     let resp = output::check_response(resp, false)?;
-    output::print_response(&resp, false);
+    output::print_response(&resp, false)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/clean.rs b/crates/pu-cli/src/commands/clean.rs
index 0569472..0c94a69 100644
--- a/crates/pu-cli/src/commands/clean.rs
+++ b/crates/pu-cli/src/commands/clean.rs
@@ -58,7 +58,7 @@ pub async fn run(
             )
             .await?;
             let resp = output::check_response(resp, json)?;
-            output::print_response(&resp, json);
+            output::print_response(&resp, json)?;
         }
     } else if let Some(wt_id) = worktree {
         let resp = client::send_request(
@@ -70,7 +70,7 @@ pub async fn run(
         )
         .await?;
         let resp = output::check_response(resp, json)?;
-        output::print_response(&resp, json);
+        output::print_response(&resp, json)?;
     }
 
     Ok(())
diff --git a/crates/pu-cli/src/commands/diff.rs b/crates/pu-cli/src/commands/diff.rs
index 91dcbf1..97eed74 100644
--- a/crates/pu-cli/src/commands/diff.rs
+++ b/crates/pu-cli/src/commands/diff.rs
@@ -24,6 +24,6 @@ pub async fn run(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/grid.rs b/crates/pu-cli/src/commands/grid.rs
index 3e2ad92..6af6870 100644
--- a/crates/pu-cli/src/commands/grid.rs
+++ b/crates/pu-cli/src/commands/grid.rs
@@ -28,11 +28,7 @@ pub async fn run(socket: &Path, action: GridAction) -> Result<(), CliError> {
             match resp {
                 Response::GridLayout { layout } => {
                     if json {
-                        println!(
-                            "{}",
-                            serde_json::to_string_pretty(&layout)
-                                .expect("layout JSON serialization failed")
-                        );
+                        println!("{}", serde_json::to_string_pretty(&layout)?);
                     } else {
                         print_ascii_grid(&layout);
                     }
diff --git a/crates/pu-cli/src/commands/health.rs b/crates/pu-cli/src/commands/health.rs
index e639d90..192ced0 100644
--- a/crates/pu-cli/src/commands/health.rs
+++ b/crates/pu-cli/src/commands/health.rs
@@ -10,6 +10,6 @@ pub async fn run(socket: &Path, json: bool) -> Result<(), CliError> {
 
     let resp = client::send_request(socket, &Request::Health).await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/kill.rs b/crates/pu-cli/src/commands/kill.rs
index 60c6889..e26020e 100644
--- a/crates/pu-cli/src/commands/kill.rs
+++ b/crates/pu-cli/src/commands/kill.rs
@@ -56,6 +56,6 @@ pub async fn run(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/logs.rs b/crates/pu-cli/src/commands/logs.rs
index bc530c4..c991642 100644
--- a/crates/pu-cli/src/commands/logs.rs
+++ b/crates/pu-cli/src/commands/logs.rs
@@ -17,6 +17,6 @@ pub async fn run(socket: &Path, agent_id: &str, tail: usize, json: bool) -> Resu
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/prompt.rs b/crates/pu-cli/src/commands/prompt.rs
index 6a5b557..56ff059 100644
--- a/crates/pu-cli/src/commands/prompt.rs
+++ b/crates/pu-cli/src/commands/prompt.rs
@@ -15,7 +15,7 @@ pub async fn run_list(socket: &Path, json: bool) -> Result<(), CliError> {
         let project_root = commands::cwd_string()?;
         let resp = client::send_request(socket, &Request::ListTemplates { project_root }).await?;
         let resp = output::check_response(resp, json)?;
-        output::print_response(&resp, json);
+        output::print_response(&resp, json)?;
         return Ok(());
     }
 
@@ -29,10 +29,7 @@ fn run_list_local(json: bool) -> Result<(), CliError> {
     let templates = template::list_templates(&cwd);
 
     if json {
-        println!(
-            "{}",
-            serde_json::to_string_pretty(&templates).expect("templates JSON serialization failed")
-        );
+        println!("{}", serde_json::to_string_pretty(&templates)?);
         return Ok(());
     }
 
@@ -73,7 +70,7 @@ pub async fn run_show(socket: &Path, name: &str, json: bool) -> Result<(), CliEr
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -102,7 +99,7 @@ pub async fn run_create(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -124,6 +121,6 @@ pub async fn run_delete(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/schedule.rs b/crates/pu-cli/src/commands/schedule.rs
index 0d06786..57d671b 100644
--- a/crates/pu-cli/src/commands/schedule.rs
+++ b/crates/pu-cli/src/commands/schedule.rs
@@ -14,7 +14,7 @@ pub async fn run_list(socket: &Path, json: bool) -> Result<(), CliError> {
     let project_root = commands::cwd_string()?;
     let resp = client::send_request(socket, &Request::ListSchedules { project_root }).await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -97,7 +97,7 @@ pub async fn run_create(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -113,7 +113,7 @@ pub async fn run_show(socket: &Path, name: &str, json: bool) -> Result<(), CliEr
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -135,7 +135,7 @@ pub async fn run_delete(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -151,7 +151,7 @@ pub async fn run_enable(socket: &Path, name: &str, json: bool) -> Result<(), Cli
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -167,7 +167,7 @@ pub async fn run_disable(socket: &Path, name: &str, json: bool) -> Result<(), Cl
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
diff --git a/crates/pu-cli/src/commands/spawn.rs b/crates/pu-cli/src/commands/spawn.rs
index a0f1892..63c5d8a 100644
--- a/crates/pu-cli/src/commands/spawn.rs
+++ b/crates/pu-cli/src/commands/spawn.rs
@@ -62,7 +62,7 @@ pub async fn run(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
diff --git a/crates/pu-cli/src/commands/status.rs b/crates/pu-cli/src/commands/status.rs
index 6290065..b1a3228 100644
--- a/crates/pu-cli/src/commands/status.rs
+++ b/crates/pu-cli/src/commands/status.rs
@@ -19,6 +19,6 @@ pub async fn run(socket: &Path, agent: Option<String>, json: bool) -> Result<(),
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
diff --git a/crates/pu-cli/src/commands/swarm.rs b/crates/pu-cli/src/commands/swarm.rs
index 6ef2279..350fb9d 100644
--- a/crates/pu-cli/src/commands/swarm.rs
+++ b/crates/pu-cli/src/commands/swarm.rs
@@ -12,7 +12,7 @@ pub async fn run_list(socket: &Path, json: bool) -> Result<(), CliError> {
     let project_root = commands::cwd_string()?;
     let resp = client::send_request(socket, &Request::ListSwarmDefs { project_root }).await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -44,7 +44,7 @@ pub async fn run_create(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -87,7 +87,7 @@ pub async fn run_show(socket: &Path, name: &str, json: bool) -> Result<(), CliEr
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -109,7 +109,7 @@ pub async fn run_delete(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
@@ -132,7 +132,7 @@ pub async fn run_run(
     )
     .await?;
     let resp = output::check_response(resp, json)?;
-    output::print_response(&resp, json);
+    output::print_response(&resp, json)?;
     Ok(())
 }
 
diff --git a/crates/pu-cli/src/output.rs b/crates/pu-cli/src/output.rs
index da59fa8..adde584 100644
--- a/crates/pu-cli/src/output.rs
+++ b/crates/pu-cli/src/output.rs
@@ -15,7 +15,7 @@ pub fn check_response(resp: Response, json: bool) -> Result<Response, CliError>
                         message: message.clone(),
                     },
                     true,
-                );
+                )?;
             }
             Err(CliError::DaemonError { code, message })
         }
@@ -34,13 +34,10 @@ fn status_colored(status: AgentStatus, exit_code: Option<i32>) -> String {
     }
 }
 
-pub fn print_response(response: &Response, json_mode: bool) {
+pub fn print_response(response: &Response, json_mode: bool) -> Result<(), CliError> {
     if json_mode {
-        println!(
-            "{}",
-            serde_json::to_string_pretty(response).expect("response JSON serialization failed")
-        );
-        return;
+        println!("{}", serde_json::to_string_pretty(response)?);
+        return Ok(());
     }
     match response {
         Response::HealthReport {
@@ -81,7 +78,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::StatusReport { worktrees, agents } => {
             if worktrees.is_empty() && agents.is_empty() {
                 println!("No active agents");
-                return;
+                return Ok(());
             }
             if !agents.is_empty() {
                 println!(
@@ -212,10 +209,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
             println!("Grid subscription active");
         }
         Response::GridLayout { layout } => {
-            println!(
-                "{}",
-                serde_json::to_string_pretty(layout).expect("layout JSON serialization failed")
-            );
+            println!("{}", serde_json::to_string_pretty(layout)?);
         }
         Response::GridEvent {
             project_root,
@@ -236,7 +230,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::TemplateList { templates } => {
             if templates.is_empty() {
                 println!("No templates");
-                return;
+                return Ok(());
             }
             println!(
                 "{:<20} {:<12} {:<10} {}",
@@ -314,7 +308,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::AgentDefList { agent_defs } => {
             if agent_defs.is_empty() {
                 println!("No agent definitions");
-                return;
+                return Ok(());
             }
             println!(
                 "{:<20} {:<12} {:<10}",
@@ -350,7 +344,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::SwarmDefList { swarm_defs } => {
             if swarm_defs.is_empty() {
                 println!("No swarm definitions");
-                return;
+                return Ok(());
             }
             println!(
                 "{:<20} {:<10} {:<10} {}",
@@ -399,7 +393,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::DiffResult { diffs } => {
             if diffs.is_empty() {
                 println!("No worktree diffs");
-                return;
+                return Ok(());
             }
             for (i, d) in diffs.iter().enumerate() {
                 if i > 0 {
@@ -432,7 +426,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
         Response::ScheduleList { schedules } => {
             if schedules.is_empty() {
                 println!("No schedules");
-                return;
+                return Ok(());
             }
             println!(
                 "{:<20} {:<10} {:<10} {:<10} {}",
@@ -500,6 +494,7 @@ pub fn print_response(response: &Response, json_mode: bool) {
             }
         }
     }
+    Ok(())
 }
 
 #[cfg(test)]
@@ -572,7 +567,7 @@ mod tests {
     fn given_json_mode_should_produce_valid_json() {
         // Exercise the print_response JSON path (which calls serde internally)
         let resp = Response::InitResult { created: true };
-        print_response(&resp, true);
+        print_response(&resp, true).unwrap();
         // Verify it round-trips through serde correctly
         let json = serde_json::to_string_pretty(&resp).unwrap();
         let parsed: serde_json::Value = serde_json::from_str(&json).unwrap();
@@ -591,17 +586,17 @@ mod tests {
             projects: vec!["/test".into()],
             agent_count: 3,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_init_result_created_should_not_panic() {
-        print_response(&Response::InitResult { created: true }, false);
+        print_response(&Response::InitResult { created: true }, false).unwrap();
     }
 
     #[test]
     fn given_init_result_already_should_not_panic() {
-        print_response(&Response::InitResult { created: false }, false);
+        print_response(&Response::InitResult { created: false }, false).unwrap();
     }
 
     #[test]
@@ -611,7 +606,7 @@ mod tests {
             agent_id: "ag-xyz".into(),
             status: AgentStatus::Streaming,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -621,7 +616,7 @@ mod tests {
             agent_id: "ag-xyz".into(),
             status: AgentStatus::Waiting,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -630,7 +625,7 @@ mod tests {
             worktrees: vec![],
             agents: vec![],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -642,7 +637,7 @@ mod tests {
                 make_agent_report("ag-2", AgentStatus::Broken),
             ],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -674,13 +669,13 @@ mod tests {
             worktrees: vec![wt],
             agents: vec![],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_agent_status_should_not_panic() {
         let resp = Response::AgentStatus(make_agent_report("ag-1", AgentStatus::Waiting));
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -690,7 +685,7 @@ mod tests {
             exit_codes: std::collections::HashMap::new(),
             skipped: vec![],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -698,7 +693,7 @@ mod tests {
         let resp = Response::SuspendResult {
             suspended: vec!["ag-1".into()],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -707,7 +702,7 @@ mod tests {
             agent_id: "ag-1".into(),
             status: AgentStatus::Streaming,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -716,7 +711,7 @@ mod tests {
             agent_id: "ag-1".into(),
             name: "new-name".into(),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -727,7 +722,7 @@ mod tests {
             branch_deleted: true,
             remote_deleted: false,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -736,12 +731,12 @@ mod tests {
             agent_id: "ag-1".into(),
             data: "some log output\n".into(),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_shutting_down_should_not_panic() {
-        print_response(&Response::ShuttingDown, false);
+        print_response(&Response::ShuttingDown, false).unwrap();
     }
 
     #[test]
@@ -750,12 +745,12 @@ mod tests {
             code: "ERR".into(),
             message: "something failed".into(),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_ok_response_should_not_panic() {
-        print_response(&Response::Ok, false);
+        print_response(&Response::Ok, false).unwrap();
     }
 
     #[test]
@@ -764,7 +759,7 @@ mod tests {
             agent_id: "ag-1".into(),
             data: b"hello world".to_vec(),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -772,12 +767,12 @@ mod tests {
         let resp = Response::AttachReady {
             buffered_bytes: 1024,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_grid_subscribed_should_not_panic() {
-        print_response(&Response::GridSubscribed, false);
+        print_response(&Response::GridSubscribed, false).unwrap();
     }
 
     #[test]
@@ -785,7 +780,7 @@ mod tests {
         let resp = Response::GridLayout {
             layout: serde_json::json!({"root": {"type": "leaf", "id": 1}}),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -794,12 +789,12 @@ mod tests {
             project_root: "/test".into(),
             command: GridCommand::GetLayout,
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_status_subscribed_should_not_panic() {
-        print_response(&Response::StatusSubscribed, false);
+        print_response(&Response::StatusSubscribed, false).unwrap();
     }
 
     #[test]
@@ -808,7 +803,7 @@ mod tests {
             agents: vec![],
             worktrees: vec![],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     // --- status_colored ---
@@ -860,13 +855,13 @@ mod tests {
                 error: None,
             }],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_empty_diff_result_should_not_panic() {
         let resp = Response::DiffResult { diffs: vec![] };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -884,7 +879,7 @@ mod tests {
                 error: None,
             }],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     // --- schedule output ---
@@ -909,13 +904,13 @@ mod tests {
                 created_at: chrono::Utc::now(),
             }],
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
     fn given_empty_schedule_list_should_not_panic() {
         let resp = Response::ScheduleList { schedules: vec![] };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 
     #[test]
@@ -937,6 +932,6 @@ mod tests {
             agent_name: None,
             created_at: chrono::Utc::now(),
         };
-        print_response(&resp, false);
+        print_response(&resp, false).unwrap();
     }
 }