diff --git a/__tests__/changeset-formatter.test.ts b/__tests__/changeset-formatter.test.ts
index 16c0485..7e673d8 100644
--- a/__tests__/changeset-formatter.test.ts
+++ b/__tests__/changeset-formatter.test.ts
@@ -463,4 +463,314 @@ describe('Change Set Formatter', () => {
     )
     expect(markdown).toContain('⚠️ Requires recreation: Always')
   })
+
+  test('diffs Tags arrays correctly', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Modify',
+            LogicalResourceId: 'MyParameter',
+            ResourceType: 'AWS::SSM::Parameter',
+            Replacement: 'False',
+            Scope: ['Properties'],
+            Details: [
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'Tags',
+                  RequiresRecreation: 'Never',
+                  BeforeValue: JSON.stringify([
+                    { Key: 'Version', Value: 'v1' },
+                    { Key: 'Team', Value: 'DevOps' },
+                    { Key: 'Environment', Value: 'test' }
+                  ]),
+                  AfterValue: JSON.stringify([
+                    { Key: 'Version', Value: 'v2' },
+                    { Key: 'UpdateType', Value: 'InPlace' },
+                    { Key: 'Environment', Value: 'production' }
+                  ])
+                }
+              }
+            ]
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    const markdown = generateChangeSetMarkdown(changesSummary)
+
+    expect(markdown).toContain('**Tags:**')
+    expect(markdown).toContain('**Tags.Environment:** `test` → `production`')
+    expect(markdown).toContain('**Tags.Team:** `DevOps` → (removed)')
+    expect(markdown).toContain('**Tags.UpdateType:** (added) → `InPlace`')
+    expect(markdown).toContain('**Tags.Version:** `v1` → `v2`')
+  })
+
+  test('diffs nested objects correctly', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Modify',
+            LogicalResourceId: 'MyResource',
+            ResourceType: 'AWS::Custom::Resource',
+            Replacement: 'False',
+            Scope: ['Properties'],
+            Details: [
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'Config',
+                  RequiresRecreation: 'Never',
+                  BeforeValue: JSON.stringify({
+                    Setting: 'old',
+                    Nested: { Value: 'a' }
+                  }),
+                  AfterValue: JSON.stringify({
+                    Setting: 'new',
+                    Nested: { Value: 'b' }
+                  })
+                }
+              }
+            ]
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    const markdown = generateChangeSetMarkdown(changesSummary)
+
+    expect(markdown).toContain('**Config.Setting:** `old` → `new`')
+    expect(markdown).toContain('**Config.Nested.Value:** `a` → `b`')
+  })
+
+  test('handles generic arrays as JSON strings', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Modify',
+            LogicalResourceId: 'MyResource',
+            ResourceType: 'AWS::Custom::Resource',
+            Replacement: 'False',
+            Scope: ['Properties'],
+            Details: [
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'Items',
+                  RequiresRecreation: 'Never',
+                  BeforeValue: JSON.stringify(['a', 'b']),
+                  AfterValue: JSON.stringify(['a', 'c'])
+                }
+              }
+            ]
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    const markdown = generateChangeSetMarkdown(changesSummary)
+
+    expect(markdown).toContain('**Items:**')
+    expect(markdown).toContain('["a","b"]')
+    expect(markdown).toContain('["a","c"]')
+  })
+
+  test('handles array additions and removals', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Modify',
+            LogicalResourceId: 'MyResource',
+            ResourceType: 'AWS::Custom::Resource',
+            Replacement: 'False',
+            Scope: ['Properties'],
+            Details: [
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'NewList',
+                  RequiresRecreation: 'Never',
+                  AfterValue: JSON.stringify(['x', 'y'])
+                }
+              },
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'OldList',
+                  RequiresRecreation: 'Never',
+                  BeforeValue: JSON.stringify(['a', 'b'])
+                }
+              }
+            ]
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    const markdown = generateChangeSetMarkdown(changesSummary)
+
+    expect(markdown).toContain('**NewList:** (added) → `["x","y"]`')
+    expect(markdown).toContain('**OldList:** `["a","b"]` → (removed)')
+  })
+
+  test('handles primitive value additions and removals', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Modify',
+            LogicalResourceId: 'MyResource',
+            ResourceType: 'AWS::Custom::Resource',
+            Replacement: 'False',
+            Scope: ['Properties'],
+            Details: [
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'NewProp',
+                  RequiresRecreation: 'Never',
+                  AfterValue: 'new-value'
+                }
+              },
+              {
+                Target: {
+                  Attribute: 'Properties',
+                  Name: 'OldProp',
+                  RequiresRecreation: 'Never',
+                  BeforeValue: 'old-value'
+                }
+              }
+            ]
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    const markdown = generateChangeSetMarkdown(changesSummary)
+
+    expect(markdown).toContain('**NewProp:** (added) → `new-value`')
+    expect(markdown).toContain('**OldProp:** `old-value` → (removed)')
+  })
+
+  test('displays AfterContext for Add actions in console output', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Add',
+            LogicalResourceId: 'NewBucket',
+            ResourceType: 'AWS::S3::Bucket',
+            AfterContext:
+              '{"BucketName":"my-bucket","Versioning":{"Status":"Enabled"}}'
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    displayChangeSet(changesSummary, 1, true)
+
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('Properties:')
+    )
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('BucketName')
+    )
+  })
+
+  test('displays BeforeContext for Remove actions in console output', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Remove',
+            LogicalResourceId: 'OldBucket',
+            ResourceType: 'AWS::S3::Bucket',
+            BeforeContext: '{"BucketName":"old-bucket"}'
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    displayChangeSet(changesSummary, 1, true)
+
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('Properties:')
+    )
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('BucketName')
+    )
+  })
+
+  test('handles invalid JSON in AfterContext gracefully', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Add',
+            LogicalResourceId: 'NewResource',
+            ResourceType: 'AWS::Custom::Resource',
+            AfterContext: 'invalid-json{'
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    displayChangeSet(changesSummary, 1, true)
+
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('invalid-json{')
+    )
+  })
+
+  test('handles invalid JSON in BeforeContext gracefully', () => {
+    const changesSummary = JSON.stringify({
+      changes: [
+        {
+          Type: 'Resource',
+          ResourceChange: {
+            Action: 'Remove',
+            LogicalResourceId: 'OldResource',
+            ResourceType: 'AWS::Custom::Resource',
+            BeforeContext: 'invalid-json{'
+          }
+        }
+      ],
+      totalChanges: 1,
+      truncated: false
+    })
+
+    displayChangeSet(changesSummary, 1, true)
+
+    expect(core.info).toHaveBeenCalledWith(
+      expect.stringContaining('invalid-json{')
+    )
+  })
 })
diff --git a/dist/index.js b/dist/index.js
index a163cc4..09f0b82 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -59733,6 +59733,75 @@ Object.defineProperty(exports, "__esModule", ({ value: true }));
 exports.displayChangeSet = displayChangeSet;
 exports.generateChangeSetMarkdown = generateChangeSetMarkdown;
 const core = __importStar(__nccwpck_require__(7484));
+/**
+ * Recursively diff JSON values and return formatted changes
+ */
+function diffJson(before, after, path = '') {
+    var _a, _b;
+    const lines = [];
+    // Handle arrays
+    if (Array.isArray(before) || Array.isArray(after)) {
+        const beforeArr = Array.isArray(before) ? before : [];
+        const afterArr = Array.isArray(after) ? after : [];
+        // Special case: array of {Key, Value} objects (Tags)
+        if (((_a = beforeArr[0]) === null || _a === void 0 ? void 0 : _a.Key) || ((_b = afterArr[0]) === null || _b === void 0 ? void 0 : _b.Key)) {
+            const beforeMap = new Map(beforeArr.map((t) => [t.Key, t.Value]));
+            const afterMap = new Map(afterArr.map((t) => [t.Key, t.Value]));
+            const allKeys = new Set([...beforeMap.keys(), ...afterMap.keys()]);
+            for (const key of Array.from(allKeys).sort()) {
+                const b = beforeMap.get(key);
+                const a = afterMap.get(key);
+                const prefix = path ? `${path}.${key}` : key;
+                if (b && a && b !== a)
+                    lines.push(`  - **${prefix}:** \`${b}\` → \`${a}\``);
+                else if (a && !b)
+                    lines.push(`  - **${prefix}:** (added) → \`${a}\``);
+                else if (b && !a)
+                    lines.push(`  - **${prefix}:** \`${b}\` → (removed)`);
+            }
+            return lines;
+        }
+        // Generic array - show as JSON if different
+        if (JSON.stringify(beforeArr) !== JSON.stringify(afterArr)) {
+            if (beforeArr.length && afterArr.length) {
+                lines.push(`  - **${path || 'value'}:** \`${JSON.stringify(beforeArr)}\` → \`${JSON.stringify(afterArr)}\``);
+            }
+            else if (afterArr.length) {
+                lines.push(`  - **${path || 'value'}:** (added) → \`${JSON.stringify(afterArr)}\``);
+            }
+            else if (beforeArr.length) {
+                lines.push(`  - **${path || 'value'}:** \`${JSON.stringify(beforeArr)}\` → (removed)`);
+            }
+        }
+        return lines;
+    }
+    // Handle objects
+    if ((before && typeof before === 'object') ||
+        (after && typeof after === 'object')) {
+        const beforeObj = before;
+        const afterObj = after;
+        const allKeys = new Set([
+            ...Object.keys(beforeObj || {}),
+            ...Object.keys(afterObj || {})
+        ]);
+        for (const key of allKeys) {
+            const newPath = path ? `${path}.${key}` : key;
+            lines.push(...diffJson(beforeObj === null || beforeObj === void 0 ? void 0 : beforeObj[key], afterObj === null || afterObj === void 0 ? void 0 : afterObj[key], newPath));
+        }
+        return lines;
+    }
+    // Primitives
+    if (before !== after) {
+        const prefix = path || 'value';
+        if (before && after)
+            lines.push(`  - **${prefix}:** \`${before}\` → \`${after}\``);
+        else if (after)
+            lines.push(`  - **${prefix}:** (added) → \`${after}\``);
+        else if (before)
+            lines.push(`  - **${prefix}:** \`${before}\` → (removed)`);
+    }
+    return lines;
+}
 /**
  * ANSI color codes
  */
@@ -60052,14 +60121,52 @@ function generateChangeSetMarkdown(changesSummary) {
                     if (!target)
                         continue;
                     const propName = target.Name || target.Attribute || 'Unknown';
-                    if (target.BeforeValue && target.AfterValue) {
-                        markdown += `- **${propName}:** \`${target.BeforeValue}\` → \`${target.AfterValue}\`\n`;
+                    // Try to parse as JSON and diff
+                    let diffLines = [];
+                    try {
+                        const before = target.BeforeValue
+                            ? JSON.parse(target.BeforeValue)
+                            : undefined;
+                        const after = target.AfterValue
+                            ? JSON.parse(target.AfterValue)
+                            : undefined;
+                        diffLines = diffJson(before, after, propName);
                     }
-                    else if (target.AfterValue) {
-                        markdown += `- **${propName}:** (added) → \`${target.AfterValue}\`\n`;
+                    catch (_c) {
+                        // Not JSON, use simple string diff
+                        if (target.BeforeValue && target.AfterValue) {
+                            diffLines = [
+                                `- **${propName}:** \`${target.BeforeValue}\` → \`${target.AfterValue}\``
+                            ];
+                        }
+                        else if (target.AfterValue) {
+                            diffLines = [
+                                `- **${propName}:** (added) → \`${target.AfterValue}\``
+                            ];
+                        }
+                        else if (target.BeforeValue) {
+                            diffLines = [
+                                `- **${propName}:** \`${target.BeforeValue}\` → (removed)`
+                            ];
+                        }
                     }
-                    else if (target.BeforeValue) {
-                        markdown += `- **${propName}:** \`${target.BeforeValue}\` → (removed)\n`;
+                    // Output the diff lines
+                    if (diffLines.length > 0) {
+                        if (diffLines.length === 1 && diffLines[0].startsWith('  - ')) {
+                            // Single nested line from diffJson - promote to top level
+                            markdown += `- ${diffLines[0].substring(4)}\n`;
+                        }
+                        else if (diffLines.length === 1) {
+                            // Single line already formatted
+                            markdown += `${diffLines[0]}\n`;
+                        }
+                        else {
+                            // Multiple lines - show property name and indent children
+                            markdown += `- **${propName}:**\n`;
+                            diffLines.forEach(line => {
+                                markdown += `${line}\n`;
+                            });
+                        }
                     }
                     if (target.RequiresRecreation &&
                         target.RequiresRecreation !== 'Never') {
@@ -60076,7 +60183,7 @@ function generateChangeSetMarkdown(changesSummary) {
                     markdown += JSON.stringify(afterProps, null, 2);
                     markdown += '\n```\n';
                 }
-                catch (_c) {
+                catch (_d) {
                     // Skip if can't parse
                 }
             }
@@ -60088,7 +60195,7 @@ function generateChangeSetMarkdown(changesSummary) {
                     markdown += JSON.stringify(beforeProps, null, 2);
                     markdown += '\n```\n';
                 }
-                catch (_d) {
+                catch (_e) {
                     // Skip if can't parse
                 }
             }
diff --git a/src/changeset-formatter.ts b/src/changeset-formatter.ts
index a536353..655e5dd 100644
--- a/src/changeset-formatter.ts
+++ b/src/changeset-formatter.ts
@@ -16,6 +16,88 @@ interface ChangeSetSummary {
   truncated: boolean
 }
 
+/**
+ * Recursively diff JSON values and return formatted changes
+ */
+function diffJson(before: unknown, after: unknown, path = ''): string[] {
+  const lines: string[] = []
+
+  // Handle arrays
+  if (Array.isArray(before) || Array.isArray(after)) {
+    const beforeArr = Array.isArray(before) ? before : []
+    const afterArr = Array.isArray(after) ? after : []
+
+    // Special case: array of {Key, Value} objects (Tags)
+    if (beforeArr[0]?.Key || afterArr[0]?.Key) {
+      const beforeMap = new Map(
+        beforeArr.map((t: { Key: string; Value: string }) => [t.Key, t.Value])
+      )
+      const afterMap = new Map(
+        afterArr.map((t: { Key: string; Value: string }) => [t.Key, t.Value])
+      )
+      const allKeys = new Set([...beforeMap.keys(), ...afterMap.keys()])
+
+      for (const key of Array.from(allKeys).sort()) {
+        const b = beforeMap.get(key)
+        const a = afterMap.get(key)
+        const prefix = path ? `${path}.${key}` : key
+        if (b && a && b !== a)
+          lines.push(`  - **${prefix}:** \`${b}\` → \`${a}\``)
+        else if (a && !b) lines.push(`  - **${prefix}:** (added) → \`${a}\``)
+        else if (b && !a) lines.push(`  - **${prefix}:** \`${b}\` → (removed)`)
+      }
+      return lines
+    }
+
+    // Generic array - show as JSON if different
+    if (JSON.stringify(beforeArr) !== JSON.stringify(afterArr)) {
+      if (beforeArr.length && afterArr.length) {
+        lines.push(
+          `  - **${path || 'value'}:** \`${JSON.stringify(beforeArr)}\` → \`${JSON.stringify(afterArr)}\``
+        )
+      } else if (afterArr.length) {
+        lines.push(
+          `  - **${path || 'value'}:** (added) → \`${JSON.stringify(afterArr)}\``
+        )
+      } else if (beforeArr.length) {
+        lines.push(
+          `  - **${path || 'value'}:** \`${JSON.stringify(beforeArr)}\` → (removed)`
+        )
+      }
+    }
+    return lines
+  }
+
+  // Handle objects
+  if (
+    (before && typeof before === 'object') ||
+    (after && typeof after === 'object')
+  ) {
+    const beforeObj = before as Record<string, unknown>
+    const afterObj = after as Record<string, unknown>
+    const allKeys = new Set([
+      ...Object.keys(beforeObj || {}),
+      ...Object.keys(afterObj || {})
+    ])
+    for (const key of allKeys) {
+      const newPath = path ? `${path}.${key}` : key
+      lines.push(...diffJson(beforeObj?.[key], afterObj?.[key], newPath))
+    }
+    return lines
+  }
+
+  // Primitives
+  if (before !== after) {
+    const prefix = path || 'value'
+    if (before && after)
+      lines.push(`  - **${prefix}:** \`${before}\` → \`${after}\``)
+    else if (after) lines.push(`  - **${prefix}:** (added) → \`${after}\``)
+    else if (before) lines.push(`  - **${prefix}:** \`${before}\` → (removed)`)
+  }
+
+  return lines
+}
+
 /**
  * ANSI color codes
  */
@@ -400,12 +482,48 @@ export function generateChangeSetMarkdown(changesSummary: string): string {
 
           const propName = target.Name || target.Attribute || 'Unknown'
 
-          if (target.BeforeValue && target.AfterValue) {
-            markdown += `- **${propName}:** \`${target.BeforeValue}\` → \`${target.AfterValue}\`\n`
-          } else if (target.AfterValue) {
-            markdown += `- **${propName}:** (added) → \`${target.AfterValue}\`\n`
-          } else if (target.BeforeValue) {
-            markdown += `- **${propName}:** \`${target.BeforeValue}\` → (removed)\n`
+          // Try to parse as JSON and diff
+          let diffLines: string[] = []
+          try {
+            const before = target.BeforeValue
+              ? JSON.parse(target.BeforeValue)
+              : undefined
+            const after = target.AfterValue
+              ? JSON.parse(target.AfterValue)
+              : undefined
+            diffLines = diffJson(before, after, propName)
+          } catch {
+            // Not JSON, use simple string diff
+            if (target.BeforeValue && target.AfterValue) {
+              diffLines = [
+                `- **${propName}:** \`${target.BeforeValue}\` → \`${target.AfterValue}\``
+              ]
+            } else if (target.AfterValue) {
+              diffLines = [
+                `- **${propName}:** (added) → \`${target.AfterValue}\``
+              ]
+            } else if (target.BeforeValue) {
+              diffLines = [
+                `- **${propName}:** \`${target.BeforeValue}\` → (removed)`
+              ]
+            }
+          }
+
+          // Output the diff lines
+          if (diffLines.length > 0) {
+            if (diffLines.length === 1 && diffLines[0].startsWith('  - ')) {
+              // Single nested line from diffJson - promote to top level
+              markdown += `- ${diffLines[0].substring(4)}\n`
+            } else if (diffLines.length === 1) {
+              // Single line already formatted
+              markdown += `${diffLines[0]}\n`
+            } else {
+              // Multiple lines - show property name and indent children
+              markdown += `- **${propName}:**\n`
+              diffLines.forEach(line => {
+                markdown += `${line}\n`
+              })
+            }
           }
 
           if (