diff --git a/dist/index.js b/dist/index.js
index 6b20c354..a9cc7ee0 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -41242,7 +41242,8 @@ function normalizeSweep(source, raw) {
             ms = parseDuration(raw.lookback, 'sweep.lookback');
         }
         catch (e) {
-            throw new Error(`${source}: ${e instanceof Error ? e.message : e}`);
+            // parseDuration throws only Error
+            throw new Error(`${source}: ${e instanceof Error ? e.message : /* v8 ignore next -- non-Error arm unreachable from dist/index.js; configSweep.test.ts drives it */ e}`);
         }
         if (ms <= 0) {
             throw new Error(`${source}: sweep.lookback must be longer than 0`);
@@ -42622,6 +42623,9 @@ function hasCommand(command, body) {
  * @param body - the full body of the comment
  */
 function getLineArgs(command, body) {
+    // both callers (/milestone, /retitle) run only after hasCommand matched the same pattern, so at(-1) is a string from the bundle;
+    // the hint sits on the statement because a hint on one operand of a ?? expression is not honoured
+    /* v8 ignore next -- absent-command fallback unreachable from dist/index.js; command.test.ts drives it */
     return findCommandArgs(command, body).at(-1) ?? '';
 }
 /**
@@ -46905,7 +46909,9 @@ async function run() {
         await handler(context);
     }
     catch (error) {
-        setFailed(error instanceof Error ? error.message : String(error));
+        // every handler folds its rejections into an Error (runEventHandlers, normalizeError, the jobs .catch),
+        // and the only throw that reaches this catch from the bundle is a built-in TypeError
+        setFailed(error instanceof Error ? error.message : /* v8 ignore next -- non-Error arm unreachable from dist/index.js; run.test.ts drives it */ String(error));
     }
 }
 
diff --git a/src/run.ts b/src/run.ts
index 3409d0e8..f0cb100a 100644
--- a/src/run.ts
+++ b/src/run.ts
@@ -37,6 +37,8 @@ export async function run(): Promise<void> {
     await handler(context)
   }
   catch (error) {
-    core.setFailed(error instanceof Error ? error.message : String(error))
+    // every handler folds its rejections into an Error (runEventHandlers, normalizeError, the jobs .catch),
+    // and the only throw that reaches this catch from the bundle is a built-in TypeError
+    core.setFailed(error instanceof Error ? error.message : /* v8 ignore next -- non-Error arm unreachable from dist/index.js; run.test.ts drives it */ String(error))
   }
 }
diff --git a/src/utils/command.ts b/src/utils/command.ts
index d3953163..b406f564 100644
--- a/src/utils/command.ts
+++ b/src/utils/command.ts
@@ -20,6 +20,9 @@ export function hasCommand(command: string, body: string): boolean {
  * @param body - the full body of the comment
  */
 export function getLineArgs(command: string, body: string): string {
+  // both callers (/milestone, /retitle) run only after hasCommand matched the same pattern, so at(-1) is a string from the bundle;
+  // the hint sits on the statement because a hint on one operand of a ?? expression is not honoured
+  /* v8 ignore next -- absent-command fallback unreachable from dist/index.js; command.test.ts drives it */
   return findCommandArgs(command, body).at(-1) ?? ''
 }
 
diff --git a/src/utils/config.ts b/src/utils/config.ts
index c71efa2f..057b4a65 100644
--- a/src/utils/config.ts
+++ b/src/utils/config.ts
@@ -654,7 +654,8 @@ function normalizeSweep(source: string, raw: unknown): SweepConfig {
       ms = parseDuration(raw.lookback, 'sweep.lookback')
     }
     catch (e) {
-      throw new Error(`${source}: ${e instanceof Error ? e.message : e}`)
+      // parseDuration throws only Error
+      throw new Error(`${source}: ${e instanceof Error ? e.message : /* v8 ignore next -- non-Error arm unreachable from dist/index.js; configSweep.test.ts drives it */ e}`)
     }
     if (ms <= 0) {
       throw new Error(`${source}: sweep.lookback must be longer than 0`)