diff --git a/Cargo.lock b/Cargo.lock
index ac62037b..36237b79 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4027,9 +4027,9 @@ checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
 [[package]]
 name = "heel"
-version = "0.10.0"
+version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "92b21e0932552edec5f468d427e6209474117e0add549585bdddc5f9051250e3"
+checksum = "e5e3c715cefcaf79c098fc7c326a4e4877a30fc00622f96ef3fff0e0d0a7bf15"
 dependencies = [
  "askama 0.12.1",
  "async-channel",
diff --git a/patch/third-party-tools.json b/patch/third-party-tools.json
index 56bf6930..7f8c2efe 100644
--- a/patch/third-party-tools.json
+++ b/patch/third-party-tools.json
@@ -452,78 +452,78 @@
     },
     {
       "tool": "heel",
-      "version": "0.10.0",
+      "version": "0.10.1",
       "target": {
         "os": "linux",
         "arch": "aarch64"
       },
-      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.0/heel-aarch64-unknown-linux-gnu",
-      "sha256": "c570c123a4938ae352064811cd03ee352611cbc13713cc53f8d39819a52d03f1",
+      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.1/heel-aarch64-unknown-linux-gnu",
+      "sha256": "75667a4d8cb988c016494b4ca5c24ae776d58918fbd16a94ff7f42ffdae02094",
       "size": 4596960,
       "encoding": {
         "format": "executable"
       },
-      "executable_sha256": "c570c123a4938ae352064811cd03ee352611cbc13713cc53f8d39819a52d03f1"
+      "executable_sha256": "75667a4d8cb988c016494b4ca5c24ae776d58918fbd16a94ff7f42ffdae02094"
     },
     {
       "tool": "heel",
-      "version": "0.10.0",
+      "version": "0.10.1",
       "target": {
         "os": "linux",
         "arch": "x86_64"
       },
-      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.0/heel-x86_64-unknown-linux-gnu",
-      "sha256": "0bc9a8bca5002c98b8ba8d08d23156ca1c04e61a65419232a93fd1f8a6f43d89",
+      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.1/heel-x86_64-unknown-linux-gnu",
+      "sha256": "022684b48d70d7e986ecb8f058c791271a945b9c263968f46b0907e6cd021849",
       "size": 5132184,
       "encoding": {
         "format": "executable"
       },
-      "executable_sha256": "0bc9a8bca5002c98b8ba8d08d23156ca1c04e61a65419232a93fd1f8a6f43d89"
+      "executable_sha256": "022684b48d70d7e986ecb8f058c791271a945b9c263968f46b0907e6cd021849"
     },
     {
       "tool": "heel",
-      "version": "0.10.0",
+      "version": "0.10.1",
       "target": {
         "os": "macos",
         "arch": "aarch64"
       },
-      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.0/heel-aarch64-apple-darwin",
-      "sha256": "59805477c62b499c143fb8a8cd1d8ddbffaf71efc35aa296553b2d18cbfc8582",
+      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.1/heel-aarch64-apple-darwin",
+      "sha256": "74be3a57e6b597aef483a5223246d0dd173dcf599d5312c10d9ee2e13adce63c",
       "size": 4130928,
       "encoding": {
         "format": "executable"
       },
-      "executable_sha256": "59805477c62b499c143fb8a8cd1d8ddbffaf71efc35aa296553b2d18cbfc8582"
+      "executable_sha256": "74be3a57e6b597aef483a5223246d0dd173dcf599d5312c10d9ee2e13adce63c"
     },
     {
       "tool": "heel",
-      "version": "0.10.0",
+      "version": "0.10.1",
       "target": {
         "os": "windows",
         "arch": "aarch64"
       },
-      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.0/heel-aarch64-pc-windows-msvc.exe",
-      "sha256": "cf7370f86f7d1b91556197a4b47b5a77d8ec6480b9223bc9b273c51f995ffcf5",
+      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.1/heel-aarch64-pc-windows-msvc.exe",
+      "sha256": "428a6b3e2140b00b24740b756ce5607dffed78dd48fc8062f5eae6d5e4ebeb07",
       "size": 4672000,
       "encoding": {
         "format": "executable"
       },
-      "executable_sha256": "cf7370f86f7d1b91556197a4b47b5a77d8ec6480b9223bc9b273c51f995ffcf5"
+      "executable_sha256": "428a6b3e2140b00b24740b756ce5607dffed78dd48fc8062f5eae6d5e4ebeb07"
     },
     {
       "tool": "heel",
-      "version": "0.10.0",
+      "version": "0.10.1",
       "target": {
         "os": "windows",
         "arch": "x86_64"
       },
-      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.0/heel-x86_64-pc-windows-msvc.exe",
-      "sha256": "48f66a0ecfeab2d2415d81265e6f176cd9208e212b3f3fe4b80783189513e502",
-      "size": 5570048,
+      "url": "https://github.com/May-Agent/heel/releases/download/heel-v0.10.1/heel-x86_64-pc-windows-msvc.exe",
+      "sha256": "721fc67c7d5f70bf487a7a21abd4aef1f6ca8d9a933202af1b6bf64908eea510",
+      "size": 5537280,
       "encoding": {
         "format": "executable"
       },
-      "executable_sha256": "48f66a0ecfeab2d2415d81265e6f176cd9208e212b3f3fe4b80783189513e502"
+      "executable_sha256": "721fc67c7d5f70bf487a7a21abd4aef1f6ca8d9a933202af1b6bf64908eea510"
     }
   ],
   "python": [
diff --git a/sandbox/Cargo.toml b/sandbox/Cargo.toml
index 3f4b3704..bd690fb0 100644
--- a/sandbox/Cargo.toml
+++ b/sandbox/Cargo.toml
@@ -20,7 +20,7 @@ arc-swap.workspace = true
 aither-core.workspace = true
 
 # Sandboxing
-heel = "0.10.0"
+heel = "0.10.1"
 
 # Executor for tokio integration
 executor-core = { version = "0.7", features = ["tokio"] }
diff --git a/sandbox/src/terminal.rs b/sandbox/src/terminal.rs
index 34dbeb5e..ff0b0f14 100644
--- a/sandbox/src/terminal.rs
+++ b/sandbox/src/terminal.rs
@@ -9382,20 +9382,41 @@ mod tests {
     }
 
     /// A script the sandboxed command writes into its working directory and
-    /// chmods executes — writable space also carries EXEC.
+    /// chmods executes — writable space also carries EXEC, and nothing still
+    /// holds the file open for writing when the shell runs it.
     #[cfg(unix)]
     #[tokio::test(flavor = "multi_thread")]
     async fn a_script_written_into_the_working_dir_executes() {
         let dir = tempfile::tempdir().expect("temp dir should be created");
         let tool = authority_terminal(dir.path()).await;
-        assert_eq!(
-            exit_code_of(
-                &tool,
-                "echo '#!/bin/sh\necho ok' > run.sh && chmod +x run.sh && ./run.sh",
+        let result = tool
+            .call(
+                terminal_args(
+                    "write and run a script",
+                    "echo '#!/bin/sh\necho ok' > run.sh && chmod +x run.sh && ./run.sh",
+                ),
+                ToolContext::new(),
             )
-            .await,
-            0,
-            "a script the command writes and chmods runs"
+            .await
+            .expect("terminal call should succeed");
+        let command = result.command().expect("the script runs as a command");
+        // The shell names the errno of a failed exec on stderr: `Text file
+        // busy` is a write descriptor still open at `execve`, `Permission
+        // denied` the sandbox refusing EXEC.
+        let stderr = command
+            .stderr
+            .as_ref()
+            .and_then(output_text)
+            .unwrap_or_default();
+        assert_eq!(
+            command.outcome,
+            CommandOutcome::Exited { code: 0 },
+            "a script the command writes and chmods runs; stderr: {stderr}"
+        );
+        assert_eq!(
+            output_text(&command.stdout).map(str::trim),
+            Some("ok"),
+            "stderr: {stderr}"
         );
     }