Stop the grader scanner reading English as code

.github/workflows/agent-contracts.yml

@@ -56,6 +56,14 @@ jobs:
         run: npm run typecheck
         working-directory: evals
 
+      # The grader import scanner decides what gets staged into the container, and a
+      # naive one already failed the build on a prose sentence. These cases are the
+      # ones it must get right — including that a genuine bare import STILL throws,
+      # since the guard's entire value is its ability to fail.
+      - name: Self-test the import scanner
+        run: npm run imports:self-test
+        working-directory: evals
+
       # Prove the graders still detect the regressions they claim to detect.
       - name: Certify graders
         run: npm run certify

evals/graders/graderHarness.ts

@@ -46,6 +46,14 @@ export const EXIT_GRADER_ERROR = 3;
  *
  * Which makes the marker more load-bearing, not less: red is now the not-applicable path, so
  * the marker is what turns a red from "mysterious failure" into "known gap, here is the fix".
+ *
+ * That sentence is left here deliberately, and is load-bearing for something other than its
+ * meaning. `stage-graders.ts` once found imports with a regex over raw source, which read the
+ * words `from "mysterious failure"` as an import of a package by that name, could not find it
+ * in `node_modules`, and failed the build for everyone on a prose sentence. The scanner is now
+ * a real tokenizer that knows what a comment is, so this line is a **regression fixture**: if
+ * anyone ever swaps that tokenizer back for a regex, the build breaks here immediately rather
+ * than on whatever sentence somebody writes next. Do not "fix" it by rewording.
  */
 export const NOT_APPLICABLE_EXIT_CODE = EXIT_GRADER_ERROR;