diff --git a/harness/pstack/claude-code/skills/statechart/scripts/run.ts b/harness/pstack/claude-code/skills/statechart/scripts/run.ts
index 4efd368e5..daa320468 100644
--- a/harness/pstack/claude-code/skills/statechart/scripts/run.ts
+++ b/harness/pstack/claude-code/skills/statechart/scripts/run.ts
@@ -212,7 +212,7 @@ async function findTlc(cwd: string) {
   };
 }
 
-const exitClass = (status: number | null) =>
+const exitClass = (status: number | null): CheckResult["exit"] =>
   status === 0 ? 0 : status === 11 || status === 12 || status === 13 ? 1 : 2;
 
 const tail = (r: FileResult) => {
diff --git a/harness/pstack/claude-code/skills/statechart/scripts/test/cli.test.ts b/harness/pstack/claude-code/skills/statechart/scripts/test/cli.test.ts
index 97b71c30c..c1f6be4b7 100644
--- a/harness/pstack/claude-code/skills/statechart/scripts/test/cli.test.ts
+++ b/harness/pstack/claude-code/skills/statechart/scripts/test/cli.test.ts
@@ -427,8 +427,8 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
   test(
     `${signal} while the view draws the chart stops the command, and it writes nothing`,
     { timeout: 60_000 },
-    () =>
-      signalWhile(signal, (fakes) => {
+    async () => {
+      await signalWhile(signal, (fakes) => {
         const drawing = path.join(fakes, "drawing");
         const dir = copyCase("Login", (d) =>
           fs.writeFileSync(
@@ -444,14 +444,15 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
           ),
         );
         return { dir, reached: () => fs.existsSync(drawing) };
-      }),
+      });
+    },
   );
 
   test(
     `${signal} while the command writes its files stops it, and it writes nothing`,
     { timeout: 60_000 },
-    () =>
-      signalWhile(signal, () => ({
+    async () => {
+      await signalWhile(signal, () => ({
         dir: gridCase(150),
         reached: (parent) => {
           for (const f of fs.readdirSync(parent, { recursive: true, encoding: "utf8" }))
@@ -462,7 +463,8 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
               return true;
           return false;
         },
-      })),
+      }));
+    },
   );
 }
 
diff --git a/pstack/skills/statechart/scripts/run.ts b/pstack/skills/statechart/scripts/run.ts
index 4efd368e5..daa320468 100644
--- a/pstack/skills/statechart/scripts/run.ts
+++ b/pstack/skills/statechart/scripts/run.ts
@@ -212,7 +212,7 @@ async function findTlc(cwd: string) {
   };
 }
 
-const exitClass = (status: number | null) =>
+const exitClass = (status: number | null): CheckResult["exit"] =>
   status === 0 ? 0 : status === 11 || status === 12 || status === 13 ? 1 : 2;
 
 const tail = (r: FileResult) => {
diff --git a/pstack/skills/statechart/scripts/test/cli.test.ts b/pstack/skills/statechart/scripts/test/cli.test.ts
index 97b71c30c..c1f6be4b7 100644
--- a/pstack/skills/statechart/scripts/test/cli.test.ts
+++ b/pstack/skills/statechart/scripts/test/cli.test.ts
@@ -427,8 +427,8 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
   test(
     `${signal} while the view draws the chart stops the command, and it writes nothing`,
     { timeout: 60_000 },
-    () =>
-      signalWhile(signal, (fakes) => {
+    async () => {
+      await signalWhile(signal, (fakes) => {
         const drawing = path.join(fakes, "drawing");
         const dir = copyCase("Login", (d) =>
           fs.writeFileSync(
@@ -444,14 +444,15 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
           ),
         );
         return { dir, reached: () => fs.existsSync(drawing) };
-      }),
+      });
+    },
   );
 
   test(
     `${signal} while the command writes its files stops it, and it writes nothing`,
     { timeout: 60_000 },
-    () =>
-      signalWhile(signal, () => ({
+    async () => {
+      await signalWhile(signal, () => ({
         dir: gridCase(150),
         reached: (parent) => {
           for (const f of fs.readdirSync(parent, { recursive: true, encoding: "utf8" }))
@@ -462,7 +463,8 @@ for (const signal of ["SIGINT", "SIGTERM"] satisfies NodeJS.Signals[]) {
               return true;
           return false;
         },
-      })),
+      }));
+    },
   );
 }