diff --git a/test/flow_yaml_controller_test.dart b/test/flow_yaml_controller_test.dart
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+// Tests for FlowYamlCodeController's type-token recolouring.
+//
+// The controller post-processes the YAML highlighter's span
+// tree to recolour any `key: <type>` value where the value is
+// one of `text|json|bytes|file|number|integer` and the key sits
+// at an indented depth (so top-level `name: text` doesn't
+// false-match). We can't easily inspect TextSpan colours without
+// rendering, so the tests below render the controller into a
+// CodeField inside a TestWidget tree and walk the produced
+// span tree.
+
+import 'package:fai_studio_flow_editor/src/flow_yaml_controller.dart';
+import 'package:fai_studio_flow_editor/src/wire_colors.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  group('FlowYamlCodeController type-token recoloring', () {
+    testWidgets('colours indented `field: bytes` value with bytes wire hue', (
+      tester,
+    ) async {
+      final c = FlowYamlCodeController();
+      addTearDown(c.dispose);
+      c.fullText = '''
+inputs:
+  document: bytes
+''';
+      late TextSpan span;
+      late ThemeData theme;
+      await tester.pumpWidget(
+        MaterialApp(
+          home: Builder(
+            builder: (context) {
+              theme = Theme.of(context);
+              span = c.buildTextSpan(context: context, withComposing: false);
+              return const SizedBox();
+            },
+          ),
+        ),
+      );
+      // Let CodeController's 500ms analyzer debounce fire so
+      // the test teardown isn't blocked by a pending timer.
+      await tester.pump(const Duration(seconds: 1));
+
+      final tokens = _flattenLeaves(span);
+      // Find the leaf whose text is the word "bytes" and assert
+      // it carries the wire-bytes colour from the shared palette.
+      final bytesLeaf = tokens.firstWhere(
+        (t) => t.text == 'bytes',
+        orElse: () => const _Leaf('', null),
+      );
+      expect(bytesLeaf.text, 'bytes', reason: 'expected a "bytes" leaf');
+      final expected = wireColor('bytes', theme);
+      expect(bytesLeaf.style?.color, expected);
+      expect(bytesLeaf.style?.fontWeight, FontWeight.w600);
+    });
+
+    testWidgets('does NOT recolour top-level `name: text` (not indented)', (
+      tester,
+    ) async {
+      final c = FlowYamlCodeController();
+      addTearDown(c.dispose);
+      // The flow's top-level `name: hello` is also not a type
+      // declaration; we use `text` here to make the trap
+      // explicit. The leading `name:` is at column 0 — not
+      // indented — so the recolour must skip it.
+      c.fullText = 'name: text\n';
+      late TextSpan span;
+      late ThemeData theme;
+      await tester.pumpWidget(
+        MaterialApp(
+          home: Builder(
+            builder: (context) {
+              theme = Theme.of(context);
+              span = c.buildTextSpan(context: context, withComposing: false);
+              return const SizedBox();
+            },
+          ),
+        ),
+      );
+      // Let CodeController's 500ms analyzer debounce fire so
+      // the test teardown isn't blocked by a pending timer.
+      await tester.pump(const Duration(seconds: 1));
+
+      final tokens = _flattenLeaves(span);
+      final textLeaf = tokens.firstWhere(
+        (t) => t.text == 'text',
+        orElse: () => const _Leaf('', null),
+      );
+      // At top level the highlighter does paint it as a string
+      // (green-ish, palette-derived), but it must NOT match the
+      // explicit wire-text hue + 600 weight combo our recolour
+      // applies — that's the signal we'd be incorrectly tagging
+      // it as a type declaration.
+      final wireText = wireColor('text', theme);
+      final isRecoloured =
+          textLeaf.style?.color == wireText &&
+          textLeaf.style?.fontWeight == FontWeight.w600;
+      expect(
+        isRecoloured,
+        isFalse,
+        reason: 'top-level `name: text` must not be flagged as a type decl',
+      );
+    });
+
+    testWidgets('colours `type: text` value (explicit-type module shape)', (
+      tester,
+    ) async {
+      final c = FlowYamlCodeController();
+      addTearDown(c.dispose);
+      c.fullText = '''
+inputs:
+  - name: pdf
+    type: bytes
+''';
+      late TextSpan span;
+      late ThemeData theme;
+      await tester.pumpWidget(
+        MaterialApp(
+          home: Builder(
+            builder: (context) {
+              theme = Theme.of(context);
+              span = c.buildTextSpan(context: context, withComposing: false);
+              return const SizedBox();
+            },
+          ),
+        ),
+      );
+      // Let CodeController's 500ms analyzer debounce fire so
+      // the test teardown isn't blocked by a pending timer.
+      await tester.pump(const Duration(seconds: 1));
+
+      final tokens = _flattenLeaves(span);
+      final bytesLeaves = tokens.where((t) => t.text == 'bytes').toList();
+      expect(bytesLeaves, isNotEmpty);
+      final expected = wireColor('bytes', theme);
+      // Every `bytes` leaf in this snippet is the type value of
+      // the `type: bytes` line.
+      for (final leaf in bytesLeaves) {
+        expect(leaf.style?.color, expected);
+      }
+    });
+  });
+}
+
+class _Leaf {
+  final String text;
+  final TextStyle? style;
+  const _Leaf(this.text, this.style);
+}
+
+List<_Leaf> _flattenLeaves(InlineSpan span) {
+  final out = <_Leaf>[];
+  void visit(InlineSpan s, TextStyle? inherited) {
+    if (s is! TextSpan) return;
+    final merged = inherited == null
+        ? s.style
+        : (s.style == null ? inherited : inherited.merge(s.style));
+    final t = s.text;
+    if (t != null && t.isNotEmpty) out.add(_Leaf(t, merged));
+    final children = s.children;
+    if (children != null) {
+      for (final c in children) visit(c, merged);
+    }
+  }
+
+  visit(span, null);
+  return out;
+}