diff --git a/src/apps/cli/src/ui/login_form.rs b/src/apps/cli/src/ui/login_form.rs
index d1520df88c..07abe834ec 100644
--- a/src/apps/cli/src/ui/login_form.rs
+++ b/src/apps/cli/src/ui/login_form.rs
@@ -411,7 +411,7 @@ fn truncate_id(id: &str) -> String {
     if id.len() <= 8 {
         id.to_string()
     } else {
-        format!("{}…", &id[..8])
+        format!("{}…", id.chars().take(8).collect::<String>())
     }
 }
 
@@ -419,6 +419,12 @@ fn truncate_id(id: &str) -> String {
 mod tests {
     use super::*;
     use crossterm::event::KeyModifiers;
+
+    #[test]
+    fn truncate_id_handles_multibyte_ids() {
+        assert_eq!(truncate_id(&"中".repeat(9)), format!("{}…", "中".repeat(8)));
+    }
+
     #[test]
     fn enter_starts_or_checks_the_host_owned_authorization() {
         let mut form = LoginFormState::new();
diff --git a/src/crates/assembly/core/src/agentic/tools/pipeline/tool_pipeline.rs b/src/crates/assembly/core/src/agentic/tools/pipeline/tool_pipeline.rs
index 297686ebcc..a0de4b992d 100644
--- a/src/crates/assembly/core/src/agentic/tools/pipeline/tool_pipeline.rs
+++ b/src/crates/assembly/core/src/agentic/tools/pipeline/tool_pipeline.rs
@@ -16,8 +16,8 @@ use crate::agentic::tools::tool_result_storage;
 #[cfg(feature = "opencode-plugin-host")]
 use crate::agentic::WorkspaceBinding;
 use crate::native_hooks::{self, NativeHookSessionFacts};
-use crate::util::elapsed_ms_u64;
 use crate::util::errors::{OpenBitFunError, OpenBitFunResult};
+use crate::util::{elapsed_ms_u64, truncate_at_char_boundary};
 use futures::future::join_all;
 use log::{debug, error, info, warn};
 use openbitfun_agent_runtime::permission::{
@@ -735,7 +735,8 @@ fn approval_resource_summary(resource: &str) -> String {
         }
     }
     if summary.len() > 160 {
-        summary.truncate(160);
+        let boundary = truncate_at_char_boundary(&summary, 160).len();
+        summary.truncate(boundary);
         summary.push('…');
     }
     summary
@@ -3766,6 +3767,14 @@ mod tests {
     use std::time::SystemTime;
     use tokio::time::{sleep, Duration};
 
+    #[test]
+    fn approval_resource_summary_truncates_multibyte_text_safely() {
+        let summary = approval_resource_summary(&"中".repeat(54));
+
+        assert_eq!(summary, format!("{}…", "中".repeat(53)));
+        assert!(summary.is_char_boundary(summary.len()));
+    }
+
     fn loaded_spec(tool_name: &str, catalog_generation: u64) -> LoadedDeferredToolSpec {
         LoadedDeferredToolSpec {
             tool_name: tool_name.to_string(),
diff --git a/src/crates/assembly/core/src/service_agent_runtime.rs b/src/crates/assembly/core/src/service_agent_runtime.rs
index a5b757af57..798041c8a1 100644
--- a/src/crates/assembly/core/src/service_agent_runtime.rs
+++ b/src/crates/assembly/core/src/service_agent_runtime.rs
@@ -3340,7 +3340,7 @@ impl RemoteDialogRuntimeHost for CoreRemoteDialogRuntimeHost<'_> {
                 return;
             }
             let workspace = binding_workspace_for_terminal;
-            let name = format!("Chat-{}", &sid[..8.min(sid.len())]);
+            let name = format!("Chat-{}", sid.chars().take(8).collect::<String>());
             match binding
                 .get_or_create(
                     &sid,
diff --git a/src/crates/services/terminal/src/session/binding.rs b/src/crates/services/terminal/src/session/binding.rs
index 98fe039f23..25af4e9827 100644
--- a/src/crates/services/terminal/src/session/binding.rs
+++ b/src/crates/services/terminal/src/session/binding.rs
@@ -100,14 +100,14 @@ impl TerminalSessionBinding {
         let terminal_session_id = options.session_id.unwrap_or_else(|| {
             format!(
                 "term-{}-{}",
-                &owner_id[..8.min(owner_id.len())],
+                owner_id.chars().take(8).collect::<String>(),
                 &uuid::Uuid::new_v4().to_string()[..8]
             )
         });
 
-        let session_name = options
-            .session_name
-            .unwrap_or_else(|| format!("Terminal-{}", &owner_id[..8.min(owner_id.len())]));
+        let session_name = options.session_name.unwrap_or_else(|| {
+            format!("Terminal-{}", owner_id.chars().take(8).collect::<String>())
+        });
 
         // Create the session
         let _session = session_manager
@@ -185,14 +185,17 @@ impl TerminalSessionBinding {
         let session_id = options.session_id.unwrap_or_else(|| {
             format!(
                 "bg-{}-{}",
-                &owner_id[..8.min(owner_id.len())],
+                owner_id.chars().take(8).collect::<String>(),
                 &uuid::Uuid::new_v4().to_string()[..8]
             )
         });
 
-        let session_name = options
-            .session_name
-            .unwrap_or_else(|| format!("Background-{}", &session_id[..8.min(session_id.len())]));
+        let session_name = options.session_name.unwrap_or_else(|| {
+            format!(
+                "Background-{}",
+                session_id.chars().take(8).collect::<String>()
+            )
+        });
 
         let _session = session_manager
             .create_session(
diff --git a/src/crates/services/terminal/src/session/manager.rs b/src/crates/services/terminal/src/session/manager.rs
index 29d83c963c..8228298664 100644
--- a/src/crates/services/terminal/src/session/manager.rs
+++ b/src/crates/services/terminal/src/session/manager.rs
@@ -690,7 +690,12 @@ impl SessionManager {
         });
 
         // Generate name
-        let name = name.unwrap_or_else(|| format!("Terminal {}", &session_id[..8]));
+        let name = name.unwrap_or_else(|| {
+            format!(
+                "Terminal {}",
+                session_id.chars().take(8).collect::<String>()
+            )
+        });
 
         // Generate nonce for shell integration
         let nonce = uuid::Uuid::new_v4().to_string();