diff --git a/.github/workflows/CI.yaml b/.github/workflows/CI.yaml
index 879fbfe7..6242ecfc 100644
--- a/.github/workflows/CI.yaml
+++ b/.github/workflows/CI.yaml
@@ -57,6 +57,7 @@ jobs:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
       - uses: ./.github/workflows/install-pinned-toolchains
       - run: make setup
+      - run: make test-json-schemas
       - run: make lint-js
 
   build-x86_64-apple-darwin:
diff --git a/Makefile b/Makefile
index b17b4a5f..7c30b084 100644
--- a/Makefile
+++ b/Makefile
@@ -13,11 +13,16 @@ setup: setup-js setup-gitignore-dirs setup-rust
 .PHONY: test
 test: \
 	test-warning \
+	test-json-schemas \
 	test-rust \
 	test-rust-ffi \
 	benchmark-rust \
 	test-scripts
 
+.PHONY: test-json-schemas
+test-json-schemas: setup-js
+	bun run -- 'script/validate-json-schemas.ts'
+
 .PHONY: test-warning
 test-warning:
 	@echo "Warning: tests are slow to run right now."
diff --git a/script/validate-json-schemas.ts b/script/validate-json-schemas.ts
new file mode 100644
index 00000000..088aedce
--- /dev/null
+++ b/script/validate-json-schemas.ts
@@ -0,0 +1,54 @@
+import { spawnSync } from "node:child_process";
+import { readdir } from "node:fs/promises";
+import path from "node:path";
+
+const schemaRoot = "node_modules/cubing/experimental-json-schema/kpuzzle";
+const sources = ["samples", "src/lib/scramble/puzzles/definitions"];
+
+async function jsonFiles(directory: string): Promise<string[]> {
+  const entries = await readdir(directory, { withFileTypes: true });
+  const nested = await Promise.all(
+    entries.map(async (entry) => {
+      const entryPath = path.join(directory, entry.name);
+      if (entry.isDirectory()) {
+        return jsonFiles(entryPath);
+      }
+      return entry.isFile() && entry.name.endsWith(".json") ? [entryPath] : [];
+    }),
+  );
+  return nested.flat();
+}
+
+const files = (await Promise.all(sources.map(jsonFiles))).flat().sort();
+if (files.length === 0) {
+  throw new Error("No sample or puzzle definition JSON files were found.");
+}
+
+const schemas = new Map<string, string[]>();
+for (const file of files) {
+  const schemaName =
+    file.endsWith(".def.json") || file.endsWith(".kpuzzle.json")
+      ? "KPuzzleDefinition.schema.json"
+      : "KPatternData.schema.json";
+  const schema = path.posix.join(schemaRoot, schemaName);
+  const group = schemas.get(schema) ?? [];
+  group.push(file.replaceAll(path.sep, "/"));
+  schemas.set(schema, group);
+}
+
+for (const [schema, dataFiles] of schemas) {
+  const args = ["x", "ajv-cli@5.0.0", "validate", "-s", schema];
+  for (const file of dataFiles) {
+    args.push("-d", file);
+  }
+
+  const result = spawnSync(process.execPath, args, { stdio: "inherit" });
+  if (result.error) {
+    throw result.error;
+  }
+  if (result.status !== 0) {
+    process.exit(result.status ?? 1);
+  }
+}
+
+console.log(`Validated ${files.length} sample and puzzle JSON files.`);