diff --git a/.jscpd.json b/.jscpd.json
index 1945b32..88773b1 100644
--- a/.jscpd.json
+++ b/.jscpd.json
@@ -1,8 +1,14 @@
 {
-	"threshold": 5,
+	"threshold": 3,
 	"minLines": 5,
 	"minTokens": 50,
-	"pattern": ["**/*.ts", "**/*.tsx"],
-	"ignore": ["node_modules", "dist", "build", "coverage", ".specify", "specs"],
+	"pattern": "**/*.{ts,tsx}",
+	"ignore": [
+		"**/node_modules/**",
+		"**/dist/**",
+		"**/build/**",
+		"**/coverage/**",
+		"**/__tests__/**"
+	],
 	"reporters": ["console"]
 }
diff --git a/lefthook.yml b/lefthook.yml
index 8a344c4..dfd08f4 100644
--- a/lefthook.yml
+++ b/lefthook.yml
@@ -14,7 +14,7 @@ pre-commit:
     - name: check-props
       run: node scripts/check-component-props.mjs
     - name: jscpd
-      run: pnpm exec jscpd
+      run: pnpm jscpd
     - name: jsinspect
       run: pnpm jsinspect
     - name: typecheck-oxlint-test
diff --git a/package.json b/package.json
index 6cddaf8..2eabb44 100644
--- a/package.json
+++ b/package.json
@@ -23,12 +23,12 @@
 		"test": "vitest run",
 		"test:watch": "vitest",
 		"knip": "knip",
-		"jscpd": "jscpd",
+		"jscpd": "jscpd apps/web/src packages/domain/src packages/application/src",
 		"jsinspect": "jsinspect -c .jsinspectrc apps/web/src packages/domain/src packages/application/src",
 		"oxlint": "oxlint --tsconfig tsconfig.json --type-aware --deny-warnings",
 		"check:ignores": "node scripts/check-lint-ignores.mjs",
 		"check:classnames": "node scripts/check-cn-classnames.mjs",
 		"check:props": "node scripts/check-component-props.mjs",
-		"check": "pnpm audit --audit-level=high && knip && biome check . && node scripts/check-lint-ignores.mjs && node scripts/check-cn-classnames.mjs && node scripts/check-component-props.mjs && jscpd && pnpm jsinspect && tsc --build && pnpm oxlint && vitest run"
+		"check": "pnpm audit --audit-level=high && knip && biome check . && node scripts/check-lint-ignores.mjs && node scripts/check-cn-classnames.mjs && node scripts/check-component-props.mjs && pnpm jscpd && pnpm jsinspect && tsc --build && pnpm oxlint && vitest run"
 	}
 }
diff --git a/scripts/check-gates.mjs b/scripts/check-gates.mjs
index cc941f8..b69cad8 100644
--- a/scripts/check-gates.mjs
+++ b/scripts/check-gates.mjs
@@ -63,6 +63,12 @@ export function checkGates() {
 		violations.push("vitest.config.ts sets passWithNoTests");
 	}
 
+	// jscpd's pattern is a single glob string. An array matches no files, and
+	// the run then reports success having read nothing.
+	if (Array.isArray(JSON.parse(read(".jscpd.json")).pattern)) {
+		violations.push(".jscpd.json sets pattern to an array, not a glob string");
+	}
+
 	// The canary rule below is not type-aware, so the probe alone cannot
 	// detect type-aware rules being switched off.
 	if (!scripts.oxlint.includes("--type-aware")) {