diff --git a/packages/examples/packages/bip32/snap.manifest.json b/packages/examples/packages/bip32/snap.manifest.json
index a614a56a11..59e5af2fde 100644
--- a/packages/examples/packages/bip32/snap.manifest.json
+++ b/packages/examples/packages/bip32/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "oIth1iwHikuY19tkSxTGtl4YzdX1XAiGn2RJl+DAeCs=",
+    "shasum": "5o3Zg3/1/23XKZdIzzo1Sbwmp2uQNF1EpnzyLYqhfqo=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/bip44/snap.manifest.json b/packages/examples/packages/bip44/snap.manifest.json
index fff1ffa89f..a7b95f7390 100644
--- a/packages/examples/packages/bip44/snap.manifest.json
+++ b/packages/examples/packages/bip44/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "Ta9rEMnKSdYz7ecxZh++RZyMSW9JVsQVqa+zFLLO87k=",
+    "shasum": "K0uZKIJkRUzXrIrbcNY/hjouFPSEVScyeJc0D5SvuIs=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/browserify-plugin/snap.manifest.json b/packages/examples/packages/browserify-plugin/snap.manifest.json
index a29e965971..4e0b2c8fbe 100644
--- a/packages/examples/packages/browserify-plugin/snap.manifest.json
+++ b/packages/examples/packages/browserify-plugin/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "q9RIkIkHMu7cVWgMRnqa0iLb7gzeYAk9LA6WXlEJkUg=",
+    "shasum": "zjj26VuJEMPd17W0vAdpVONDt/JeYPacP5GwbRAiQZo=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/browserify/snap.manifest.json b/packages/examples/packages/browserify/snap.manifest.json
index 2a633d6a81..a37da4aaa7 100644
--- a/packages/examples/packages/browserify/snap.manifest.json
+++ b/packages/examples/packages/browserify/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "Sehc3xVJmoP4CBbyL64schgPUfHu7Labnrtk5i5LH88=",
+    "shasum": "WEO5ozYWnfy690WSCYKkexaQnlkDbks1f+vXrRVQRTM=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/cronjobs/snap.manifest.json b/packages/examples/packages/cronjobs/snap.manifest.json
index e4e9dd2b74..db31729895 100644
--- a/packages/examples/packages/cronjobs/snap.manifest.json
+++ b/packages/examples/packages/cronjobs/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "o5qiOur9Zl+yAjHScLzh0FfK7/jcKx7rGqotitpJ6Uo=",
+    "shasum": "jcA6NL+j9BPrnOiv5FOl+KnTyxAJ5UdThThk4zCoiu8=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/dialogs/snap.manifest.json b/packages/examples/packages/dialogs/snap.manifest.json
index 67035ee16f..019f02ba02 100644
--- a/packages/examples/packages/dialogs/snap.manifest.json
+++ b/packages/examples/packages/dialogs/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "77wtrsk6BY8OSjG5pWALMSJzOmznWaaR7EiM3LGigjI=",
+    "shasum": "P+jpppDqo3e+Dsyk2KP+26NlKDyGwW+CxztRYiDkqnQ=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/ethers-js/snap.manifest.json b/packages/examples/packages/ethers-js/snap.manifest.json
index 598841f513..987a77f9f3 100644
--- a/packages/examples/packages/ethers-js/snap.manifest.json
+++ b/packages/examples/packages/ethers-js/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "fwMTtk4KJjak+yf6666Vv/+syXmFVAnVPAsBkalK2Qc=",
+    "shasum": "ARrlf69swjj7vnhGGRLajr4MFr4hbKbh9G5R987WFoo=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/get-entropy/snap.manifest.json b/packages/examples/packages/get-entropy/snap.manifest.json
index 537974b0a1..35b3c35dff 100644
--- a/packages/examples/packages/get-entropy/snap.manifest.json
+++ b/packages/examples/packages/get-entropy/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "ur2Jxp1kniP1jYLeexXHTB/+dgfJom1volcPQgSNX6c=",
+    "shasum": "dPssrjujrDEsuDMxogdHlFNJbGtuZjTpwwU5Lirbr6A=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/images/snap.manifest.json b/packages/examples/packages/images/snap.manifest.json
index 1e8c4f2536..5374917662 100644
--- a/packages/examples/packages/images/snap.manifest.json
+++ b/packages/examples/packages/images/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "ewEvZGj7D/wUtBH8bDutuDuJ1leq8n9Penuu8yDAykA=",
+    "shasum": "lNV3t5b0qgpl6fMuTUdFA75wWL3zFzm3MvEokB8VF5U=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/invoke-snap/packages/core-signer/snap.manifest.json b/packages/examples/packages/invoke-snap/packages/core-signer/snap.manifest.json
index 2516ea1744..4a6144b766 100644
--- a/packages/examples/packages/invoke-snap/packages/core-signer/snap.manifest.json
+++ b/packages/examples/packages/invoke-snap/packages/core-signer/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "Y0k3QSqHBYytNfYgmtrjwhbZ3e8WzXhOQFYPJCIuJfg=",
+    "shasum": "nBYyvFGnEv4kGTgEAvmhbfAafd85Z1dxbQTczGahxvA=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/lifecycle-hooks/snap.manifest.json b/packages/examples/packages/lifecycle-hooks/snap.manifest.json
index e044675125..0a6c94324e 100644
--- a/packages/examples/packages/lifecycle-hooks/snap.manifest.json
+++ b/packages/examples/packages/lifecycle-hooks/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "Huxm0NrX6zvh0k9iGnStycNNcmHSGRK1EK/+jmv7nyI=",
+    "shasum": "Mgf0SLyA7yvGJ3+3y8f/Nf2GuMUzLHt4zRj8ZwVoC08=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/signature-insights/snap.manifest.json b/packages/examples/packages/signature-insights/snap.manifest.json
index a7fdafd08a..cbf246f896 100644
--- a/packages/examples/packages/signature-insights/snap.manifest.json
+++ b/packages/examples/packages/signature-insights/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "mxW5zlXyghmveLeZIwJMZkwjqb7Y8peJut9uvbxgLCU=",
+    "shasum": "DdjMLFOqo+SfRA4nNJflLvSX3v/IwM23QtjPYzOLG1o=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/examples/packages/transaction-insights/snap.manifest.json b/packages/examples/packages/transaction-insights/snap.manifest.json
index 9cfcc1640e..ba03473e67 100644
--- a/packages/examples/packages/transaction-insights/snap.manifest.json
+++ b/packages/examples/packages/transaction-insights/snap.manifest.json
@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "2HeDCuxgl9zngyHAGEyikHFuM3Rcek5Jc0lCeuPNFqA=",
+    "shasum": "psh5WYTtiqN1PD18OI3JLmBiMFuo8Uw0V56yiBMVZ4M=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",
diff --git a/packages/snaps-rpc-methods/jest.config.js b/packages/snaps-rpc-methods/jest.config.js
index 015ebd2bcd..106681f117 100644
--- a/packages/snaps-rpc-methods/jest.config.js
+++ b/packages/snaps-rpc-methods/jest.config.js
@@ -10,7 +10,7 @@ module.exports = deepmerge(baseConfig, {
   ],
   coverageThreshold: {
     global: {
-      branches: 92.07,
+      branches: 92.62,
       functions: 96.96,
       lines: 97.51,
       statements: 96.97,
diff --git a/packages/snaps-rpc-methods/src/permitted/createInterface.test.tsx b/packages/snaps-rpc-methods/src/permitted/createInterface.test.tsx
index 9d6c8685a4..2403d9fd56 100644
--- a/packages/snaps-rpc-methods/src/permitted/createInterface.test.tsx
+++ b/packages/snaps-rpc-methods/src/permitted/createInterface.test.tsx
@@ -1,7 +1,15 @@
 import { JsonRpcEngine } from '@metamask/json-rpc-engine';
 import { text, type CreateInterfaceResult } from '@metamask/snaps-sdk';
 import type { JSXElement } from '@metamask/snaps-sdk/jsx';
-import { Text, Box } from '@metamask/snaps-sdk/jsx';
+import {
+  Text,
+  Box,
+  Field,
+  Input,
+  Form,
+  Container,
+  Footer,
+} from '@metamask/snaps-sdk/jsx';
 import type { JsonRpcRequest, PendingJsonRpcResponse } from '@metamask/utils';
 
 import type { CreateInterfaceParameters } from './createInterface';
@@ -132,7 +140,114 @@ describe('snap_createInterface', () => {
       error: {
         code: -32602,
         message:
-          'Invalid params: At path: ui -- Expected the value to satisfy a union of `union | union`, but received: "foo".',
+          'Invalid params: At path: ui -- Expected type to be one of: "Address", "Bold", "Box", "Button", "Copyable", "Divider", "Dropdown", "RadioGroup", "FileInput", "Form", "Heading", "Input", "Image", "Italic", "Link", "Row", "Spinner", "Text", "Tooltip", "Checkbox", "Card", "Icon", "Selector", "Section", "Container", but received: undefined.',
+        stack: expect.any(String),
+      },
+      id: 1,
+      jsonrpc: '2.0',
+    });
+  });
+
+  it('throws on invalid UI', async () => {
+    const { implementation } = createInterfaceHandler;
+
+    const createInterface = jest.fn().mockReturnValue('foo');
+
+    const hooks = {
+      createInterface,
+    };
+
+    const engine = new JsonRpcEngine();
+
+    engine.push((request, response, next, end) => {
+      const result = implementation(
+        request as JsonRpcRequest<CreateInterfaceParameters>,
+        response as PendingJsonRpcResponse<CreateInterfaceResult>,
+        next,
+        end,
+        hooks,
+      );
+
+      result?.catch(end);
+    });
+
+    const response = await engine.handle({
+      jsonrpc: '2.0',
+      id: 1,
+      method: 'snap_createInterface',
+      params: {
+        ui: (
+          <Box>
+            <Field label="Input">
+              <Input name="input" />
+            </Field>
+          </Box>
+        ) as JSXElement,
+      },
+    });
+
+    expect(response).toStrictEqual({
+      error: {
+        code: -32602,
+        message:
+          'Invalid params: At path: ui.props.children -- Expected type to be one of: "Address", "Bold", "Box", "Button", "Copyable", "Divider", "Dropdown", "RadioGroup", "FileInput", "Form", "Heading", "Input", "Image", "Italic", "Link", "Row", "Spinner", "Text", "Tooltip", "Checkbox", "Card", "Icon", "Selector", "Section", but received: "Field".',
+        stack: expect.any(String),
+      },
+      id: 1,
+      jsonrpc: '2.0',
+    });
+  });
+
+  it('throws on invalid nested UI', async () => {
+    const { implementation } = createInterfaceHandler;
+
+    const createInterface = jest.fn().mockReturnValue('foo');
+
+    const hooks = {
+      createInterface,
+    };
+
+    const engine = new JsonRpcEngine();
+
+    engine.push((request, response, next, end) => {
+      const result = implementation(
+        request as JsonRpcRequest<CreateInterfaceParameters>,
+        response as PendingJsonRpcResponse<CreateInterfaceResult>,
+        next,
+        end,
+        hooks,
+      );
+
+      result?.catch(end);
+    });
+
+    const response = await engine.handle({
+      jsonrpc: '2.0',
+      id: 1,
+      method: 'snap_createInterface',
+      params: {
+        ui: (
+          <Container>
+            <Box>
+              <Form name="form">
+                <Field label="Input">
+                  <Input name="input" />
+                </Field>
+              </Form>
+            </Box>
+            <Footer>
+              <Text>Foo</Text>
+            </Footer>
+          </Container>
+        ) as JSXElement,
+      },
+    });
+
+    expect(response).toStrictEqual({
+      error: {
+        code: -32602,
+        message:
+          'Invalid params: At path: ui.props.children.1.props.children.type -- Expected the literal `"Button"`, but received: "Text".',
         stack: expect.any(String),
       },
       id: 1,
diff --git a/packages/snaps-rpc-methods/src/restricted/dialog.test.tsx b/packages/snaps-rpc-methods/src/restricted/dialog.test.tsx
index 79b58fb522..dd5d3c7fec 100644
--- a/packages/snaps-rpc-methods/src/restricted/dialog.test.tsx
+++ b/packages/snaps-rpc-methods/src/restricted/dialog.test.tsx
@@ -358,6 +358,30 @@ describe('implementation', () => {
         },
       });
     });
+
+    it('handles confirmations using an ID', async () => {
+      const hooks = getMockDialogHooks();
+      const implementation = getDialogImplementation(hooks);
+      await implementation({
+        context: { origin: 'foo' },
+        method: 'snap_dialog',
+        params: {
+          type: DialogType.Confirmation,
+          id: 'baz',
+        },
+      });
+
+      expect(hooks.requestUserApproval).toHaveBeenCalledTimes(1);
+      expect(hooks.requestUserApproval).toHaveBeenCalledWith({
+        id: undefined,
+        origin: 'foo',
+        type: DIALOG_APPROVAL_TYPES[DialogType.Confirmation],
+        requestData: {
+          id: 'baz',
+          placeholder: undefined,
+        },
+      });
+    });
   });
 
   describe('prompts', () => {
@@ -414,6 +438,31 @@ describe('implementation', () => {
         },
       });
     });
+
+    it('handles prompts using an ID', async () => {
+      const hooks = getMockDialogHooks();
+      const implementation = getDialogImplementation(hooks);
+      await implementation({
+        context: { origin: 'foo' },
+        method: 'snap_dialog',
+        params: {
+          type: DialogType.Prompt,
+          id: 'baz',
+          placeholder: 'foobar',
+        },
+      });
+
+      expect(hooks.requestUserApproval).toHaveBeenCalledTimes(1);
+      expect(hooks.requestUserApproval).toHaveBeenCalledWith({
+        id: undefined,
+        origin: 'foo',
+        type: DIALOG_APPROVAL_TYPES[DialogType.Prompt],
+        requestData: {
+          id: 'baz',
+          placeholder: 'foobar',
+        },
+      });
+    });
   });
 
   describe('validation', () => {
@@ -446,7 +495,7 @@ describe('implementation', () => {
           params: {} as any,
         }),
       ).rejects.toThrow(
-        'Invalid params: Expected the value to satisfy a union of `object | object`, but received: [object Object]',
+        /Invalid params: At path: .* -- Expected type to be one of: .*, but received: .*/u,
       );
     });
 
@@ -487,7 +536,7 @@ describe('implementation', () => {
           params: value as any,
         }),
       ).rejects.toThrow(
-        /Invalid params: At path: .* — Expected a value of type .*, but received: .*\./u,
+        /Invalid params: At path: .* -- Expected type to be one of: .*, but received: .*/u,
       );
     });
 
@@ -508,7 +557,7 @@ describe('implementation', () => {
             },
           }),
         ).rejects.toThrow(
-          /Invalid params: At path: placeholder — Expected a value of type string, but received: .*\./u,
+          /Invalid params: At path: placeholder -- Expected a string, but received: .*/u,
         );
       },
     );
@@ -528,7 +577,7 @@ describe('implementation', () => {
           },
         }),
       ).rejects.toThrow(
-        'Invalid params: At path: placeholder — Expected a string with a length between 1 and 40, but received one with a length of 0.',
+        'Invalid params: At path: placeholder -- Expected a string with a length between `1` and `40` but received one with a length of `0`',
       );
     });
 
@@ -548,7 +597,7 @@ describe('implementation', () => {
             },
           }),
         ).rejects.toThrow(
-          'Invalid params: Unknown key: placeholder, received: "foobar".',
+          'Invalid params: At path: placeholder -- Expected a value of type `never`, but received: `"foobar"`',
         );
       },
     );
diff --git a/packages/snaps-rpc-methods/src/restricted/dialog.ts b/packages/snaps-rpc-methods/src/restricted/dialog.ts
index 9f359b68a3..d4b5fb6f78 100644
--- a/packages/snaps-rpc-methods/src/restricted/dialog.ts
+++ b/packages/snaps-rpc-methods/src/restricted/dialog.ts
@@ -8,8 +8,8 @@ import { rpcErrors } from '@metamask/rpc-errors';
 import {
   DialogType,
   enumValue,
-  union,
   ComponentOrElementStruct,
+  selectiveUnion,
 } from '@metamask/snaps-sdk';
 import type {
   DialogParams,
@@ -20,19 +20,10 @@ import type {
   ComponentOrElement,
 } from '@metamask/snaps-sdk';
 import type { InferMatching } from '@metamask/snaps-utils';
-import { createUnion } from '@metamask/snaps-utils';
-import type { Infer, Struct } from '@metamask/superstruct';
-import {
-  create,
-  enums,
-  object,
-  optional,
-  size,
-  string,
-  type,
-} from '@metamask/superstruct';
+import type { Infer } from '@metamask/superstruct';
+import { create, object, optional, size, string } from '@metamask/superstruct';
 import type { Json, NonEmptyArray } from '@metamask/utils';
-import { hasProperty, isObject } from '@metamask/utils';
+import { hasProperty, isObject, isPlainObject } from '@metamask/utils';
 
 import { type MethodHooksObject } from '../utils';
 
@@ -156,27 +147,22 @@ export const dialogBuilder = Object.freeze({
   methodHooks,
 } as const);
 
-// Note: We use `type` here instead of `object` because `type` does not validate
-// the keys of the object, which is what we want.
-const BaseParamsStruct = type({
-  type: optional(
-    enums([DialogType.Alert, DialogType.Confirmation, DialogType.Prompt]),
-  ),
-});
-
 const AlertParametersWithContentStruct = object({
   type: enumValue(DialogType.Alert),
   content: ComponentOrElementStruct,
 });
+
 const AlertParametersWithIdStruct = object({
   type: enumValue(DialogType.Alert),
   id: string(),
 });
 
-const AlertParametersStruct = union([
-  AlertParametersWithContentStruct,
-  AlertParametersWithIdStruct,
-]);
+const AlertParametersStruct = selectiveUnion((value) => {
+  if (isPlainObject(value) && hasProperty(value, 'id')) {
+    return AlertParametersWithIdStruct;
+  }
+  return AlertParametersWithContentStruct;
+});
 
 const ConfirmationParametersWithContentStruct = object({
   type: enumValue(DialogType.Confirmation),
@@ -188,10 +174,12 @@ const ConfirmationParametersWithIdStruct = object({
   id: string(),
 });
 
-const ConfirmationParametersStruct = union([
-  ConfirmationParametersWithContentStruct,
-  ConfirmationParametersWithIdStruct,
-]);
+const ConfirmationParametersStruct = selectiveUnion((value) => {
+  if (isPlainObject(value) && hasProperty(value, 'id')) {
+    return ConfirmationParametersWithIdStruct;
+  }
+  return ConfirmationParametersWithContentStruct;
+});
 
 const PromptParametersWithContentStruct = object({
   type: enumValue(DialogType.Prompt),
@@ -205,10 +193,12 @@ const PromptParametersWithIdStruct = object({
   placeholder: PlaceholderStruct,
 });
 
-const PromptParametersStruct = union([
-  PromptParametersWithContentStruct,
-  PromptParametersWithIdStruct,
-]);
+const PromptParametersStruct = selectiveUnion((value) => {
+  if (isPlainObject(value) && hasProperty(value, 'id')) {
+    return PromptParametersWithIdStruct;
+  }
+  return PromptParametersWithContentStruct;
+});
 
 const DefaultParametersWithContentStruct = object({
   content: ComponentOrElementStruct,
@@ -218,29 +208,39 @@ const DefaultParametersWithIdStruct = object({
   id: string(),
 });
 
-const DefaultParametersStruct = union([
-  DefaultParametersWithContentStruct,
-  DefaultParametersWithIdStruct,
-]);
+const DefaultParametersStruct = selectiveUnion((value) => {
+  if (isPlainObject(value) && hasProperty(value, 'id')) {
+    return DefaultParametersWithIdStruct;
+  }
+  return DefaultParametersWithContentStruct;
+});
 
-const DialogParametersStruct = union([
-  AlertParametersStruct,
-  ConfirmationParametersStruct,
-  PromptParametersStruct,
-  DefaultParametersStruct,
-]);
+const DialogParametersStruct = selectiveUnion((value) => {
+  if (isPlainObject(value) && hasProperty(value, 'type')) {
+    switch (value.type) {
+      // We cannot use typedUnion here unfortunately.
+      case DialogType.Alert:
+        return AlertParametersStruct;
+      case DialogType.Confirmation:
+        return ConfirmationParametersStruct;
+      case DialogType.Prompt:
+        return PromptParametersStruct;
+      default:
+        throw new Error(
+          `The "type" property must be one of: ${Object.values(DialogType).join(
+            ', ',
+          )}.`,
+        );
+    }
+  }
+  return DefaultParametersStruct;
+});
 
 export type DialogParameters = InferMatching<
   typeof DialogParametersStruct,
   DialogParams
 >;
 
-const structs: Record<DialogType, Struct<any, any>> = {
-  [DialogType.Alert]: AlertParametersStruct,
-  [DialogType.Confirmation]: ConfirmationParametersStruct,
-  [DialogType.Prompt]: PromptParametersStruct,
-};
-
 /**
  * Builds the method implementation for `snap_dialog`.
  *
@@ -271,17 +271,20 @@ export function getDialogImplementation({
       });
     }
 
-    const validatedType = getValidatedType(params);
-
-    const approvalType = validatedType
-      ? DIALOG_APPROVAL_TYPES[validatedType]
-      : DIALOG_APPROVAL_TYPES.default;
-
-    const validatedParams = getValidatedParams(params, validatedType);
+    const validatedParams = getValidatedParams(params);
     const placeholder = isPromptDialog(validatedParams)
       ? validatedParams.placeholder
       : undefined;
 
+    const validatedType = hasProperty(validatedParams, 'type')
+      ? validatedParams.type
+      : 'default';
+
+    const approvalType =
+      DIALOG_APPROVAL_TYPES[
+        validatedType as keyof typeof DIALOG_APPROVAL_TYPES
+      ];
+
     if (hasProperty(validatedParams, 'content')) {
       const id = await createInterface(
         origin,
@@ -289,7 +292,7 @@ export function getDialogImplementation({
       );
 
       return requestUserApproval({
-        id: validatedType ? undefined : id,
+        id: approvalType === DIALOG_APPROVAL_TYPES.default ? id : undefined,
         origin,
         type: approvalType,
         requestData: { id, placeholder },
@@ -299,7 +302,10 @@ export function getDialogImplementation({
     validateInterface(origin, validatedParams.id, getInterface);
 
     return requestUserApproval({
-      id: validatedType ? undefined : validatedParams.id,
+      id:
+        approvalType === DIALOG_APPROVAL_TYPES.default
+          ? validatedParams.id
+          : undefined,
       origin,
       type: approvalType,
       requestData: { id: validatedParams.id, placeholder },
@@ -337,25 +343,6 @@ function getDialogType(params: DialogParameters): DialogType | undefined {
   return hasProperty(params, 'type') ? (params.type as DialogType) : undefined;
 }
 
-/**
- * Get the validated type of the dialog parameters. Throws an error if the type
- * is invalid.
- *
- * @param params - The parameters to validate.
- * @returns The validated type of the dialog parameters.
- */
-function getValidatedType(params: unknown): DialogType | undefined {
-  try {
-    return create(params, BaseParamsStruct).type;
-  } catch (error) {
-    throw rpcErrors.invalidParams({
-      message: `The "type" property must be one of: ${Object.values(
-        DialogType,
-      ).join(', ')}.`,
-    });
-  }
-}
-
 /**
  * Checks if the dialog parameters are for a prompt dialog.
  *
@@ -371,17 +358,11 @@ function isPromptDialog(params: DialogParameters): params is PromptDialog {
  * type. Throws if validation fails.
  *
  * @param params - The unvalidated params object from the method request.
- * @param validatedType - The validated dialog type.
  * @returns The validated confirm method parameter object.
  */
-function getValidatedParams(
-  params: unknown,
-  validatedType: DialogType | undefined,
-): DialogParameters {
+function getValidatedParams(params: unknown): DialogParameters {
   try {
-    return validatedType
-      ? createUnion(params, structs[validatedType], 'type')
-      : create(params, DefaultParametersStruct);
+    return create(params, DialogParametersStruct);
   } catch (error) {
     throw rpcErrors.invalidParams({
       message: `Invalid params: ${error.message}`,
diff --git a/packages/snaps-sdk/src/index.ts b/packages/snaps-sdk/src/index.ts
index c2a0cdd457..c90eb4c6fa 100644
--- a/packages/snaps-sdk/src/index.ts
+++ b/packages/snaps-sdk/src/index.ts
@@ -9,6 +9,8 @@ export {
   literal,
   union,
   enumValue,
+  typedUnion,
+  selectiveUnion,
 } from './internals';
 
 // Re-exported from `@metamask/utils` for convenience.
diff --git a/packages/snaps-sdk/src/internals/structs.test.ts b/packages/snaps-sdk/src/internals/structs.test.ts
index 086acbd220..2e7a007274 100644
--- a/packages/snaps-sdk/src/internals/structs.test.ts
+++ b/packages/snaps-sdk/src/internals/structs.test.ts
@@ -1,7 +1,20 @@
-import { is, validate } from '@metamask/superstruct';
-
-import { Text } from '../jsx';
-import { BoxStruct, FieldStruct, TextStruct } from '../jsx/validation';
+import {
+  create,
+  defaulted,
+  is,
+  object,
+  string,
+  validate,
+} from '@metamask/superstruct';
+
+import type { BoxElement } from '../jsx';
+import { Footer, Icon, Text, Button, Box } from '../jsx';
+import {
+  BoxStruct,
+  FieldStruct,
+  FooterStruct,
+  TextStruct,
+} from '../jsx/validation';
 import { enumValue, literal, typedUnion, union } from './structs';
 
 describe('enumValue', () => {
@@ -53,7 +66,7 @@ describe('typedUnion', () => {
     const result = validate(Text({}), unionStruct);
 
     expect(result[0]?.message).toBe(
-      'At path: props.children -- Expected the value to satisfy a union of `union | array`, but received: undefined',
+      'At path: props.children -- Expected type to be one of: "Bold", "Italic", "Link", "Icon", but received: undefined',
     );
   });
 
@@ -62,7 +75,49 @@ describe('typedUnion', () => {
     const result = validate(Text({}), nestedUnionStruct);
 
     expect(result[0]?.message).toBe(
-      'At path: props.children -- Expected the value to satisfy a union of `union | array`, but received: undefined',
+      'At path: props.children -- Expected type to be one of: "Bold", "Italic", "Link", "Icon", but received: undefined',
+    );
+  });
+
+  it('validates refined elements', () => {
+    const refinedUnionStruct = typedUnion([BoxStruct, FooterStruct]);
+    const result = validate(
+      Footer({ children: Button({ children: Icon({ name: 'wallet' }) }) }),
+      refinedUnionStruct,
+    );
+
+    expect(result[0]?.message).toBe(
+      'At path: props.children -- Footer buttons may only contain text.',
+    );
+  });
+
+  it('supports coercion', () => {
+    const coercedStruct = typedUnion([
+      BoxStruct,
+      defaulted(object({ type: literal('Custom'), key: string() }), {
+        type: 'Custom',
+        key: 'foo',
+      }),
+    ]);
+
+    const result = create({ type: 'Custom' }, coercedStruct);
+    expect(result.key).toBe('foo');
+
+    const result2 = create(
+      Box({ children: Text({ children: 'foo' }) }),
+      coercedStruct,
+    ) as BoxElement;
+    expect(result2.props.children).toStrictEqual({
+      type: 'Text',
+      key: null,
+      props: { children: 'foo' },
+    });
+
+    expect(() => create(Button({ children: 'foo' }), coercedStruct)).toThrow(
+      'Expected type to be one of: "Box", "Custom", but received: "Button"',
+    );
+    expect(() => create('foo', coercedStruct)).toThrow(
+      'Expected type to be one of: "Box", "Custom", but received: undefined',
     );
   });
 
diff --git a/packages/snaps-sdk/src/internals/structs.ts b/packages/snaps-sdk/src/internals/structs.ts
index b51bd6255d..8d559b5baf 100644
--- a/packages/snaps-sdk/src/internals/structs.ts
+++ b/packages/snaps-sdk/src/internals/structs.ts
@@ -6,6 +6,7 @@ import {
   literal as superstructLiteral,
   union as superstructUnion,
 } from '@metamask/superstruct';
+import type { PlainObject } from '@metamask/utils';
 import { hasProperty, isPlainObject } from '@metamask/utils';
 
 import type { EnumToUnion } from './helpers';
@@ -97,6 +98,7 @@ export function typedUnion<Head extends AnyStruct, Tail extends AnyStruct[]>(
         : struct,
     )
     .flat(Infinity);
+  const types = flatStructs.map(({ schema }) => schema.type.type);
   return new Struct({
     type: 'union',
     schema: flatStructs,
@@ -116,9 +118,28 @@ export function typedUnion<Head extends AnyStruct, Tail extends AnyStruct[]>(
         yield entry;
       }
     },
-    validator(value, context) {
-      const types = flatStructs.map(({ schema }) => schema.type.type);
+    coercer(value, context) {
+      if (!isPlainObject(value) || !hasProperty(value, 'type')) {
+        return value;
+      }
+
+      const { type } = value;
+      const struct = flatStructs.find(({ schema }) => is(type, schema.type));
+      if (struct) {
+        return struct.coercer(value, context);
+      }
+
+      return value;
+    },
+    // At this point we know the value to be an object.
+    *refiner(value: PlainObject, context) {
+      const struct = flatStructs.find(({ schema }) =>
+        is(value.type, schema.type),
+      );
 
+      yield* struct.refiner(value, context);
+    },
+    validator(value, context) {
       if (
         !isPlainObject(value) ||
         !hasProperty(value, 'type') ||
@@ -144,3 +165,43 @@ export function typedUnion<Head extends AnyStruct, Tail extends AnyStruct[]>(
     },
   }) as unknown as Struct<Infer<Head> | InferStructTuple<Tail>[number], null>;
 }
+
+/**
+ * Create a custom union struct that uses a `selector` function for choosing
+ * the validation path.
+ *
+ * @param selector - The selector function choosing the struct to validate with.
+ * @returns The `superstruct` struct, which validates that the value satisfies
+ * one of the structs.
+ */
+export function selectiveUnion<Selector extends (value: any) => AnyStruct>(
+  selector: Selector,
+): Struct<Infer<ReturnType<Selector>>, null> {
+  return new Struct({
+    type: 'union',
+    schema: null,
+    *entries(value, context) {
+      const struct = selector(value);
+
+      for (const entry of struct.entries(value, context)) {
+        yield entry;
+      }
+    },
+    *refiner(value, context) {
+      const struct = selector(value);
+
+      yield* struct.refiner(value, context);
+    },
+    coercer(value, context) {
+      const struct = selector(value);
+
+      return struct.coercer(value, context);
+    },
+    validator(value, context) {
+      const struct = selector(value);
+
+      // This only validates the root of the struct, entries does the rest of the work.
+      return struct.validator(value, context);
+    },
+  });
+}
diff --git a/packages/snaps-sdk/src/jsx/validation.ts b/packages/snaps-sdk/src/jsx/validation.ts
index a29941472b..7f98a654e8 100644
--- a/packages/snaps-sdk/src/jsx/validation.ts
+++ b/packages/snaps-sdk/src/jsx/validation.ts
@@ -28,7 +28,13 @@ import {
 } from '@metamask/utils';
 
 import type { Describe } from '../internals';
-import { literal, nullUnion, svg, typedUnion } from '../internals';
+import {
+  literal,
+  nullUnion,
+  selectiveUnion,
+  svg,
+  typedUnion,
+} from '../internals';
 import type { EmptyObject } from '../types';
 import type {
   GenericSnapElement,
@@ -106,10 +112,12 @@ export const ElementStruct: Describe<GenericSnapElement> = object({
 function nestable<Type, Schema>(
   struct: Struct<Type, Schema>,
 ): Struct<Nestable<Type>, any> {
-  const nestableStruct: Struct<Nestable<Type>> = nullUnion([
-    struct,
-    array(lazy(() => nestableStruct)),
-  ]);
+  const nestableStruct: Struct<Nestable<Type>> = selectiveUnion((value) => {
+    if (Array.isArray(value)) {
+      return array(lazy(() => nestableStruct));
+    }
+    return struct;
+  });
 
   return nestableStruct;
 }
@@ -127,7 +135,22 @@ function children<Head extends AnyStruct, Tail extends AnyStruct[]>(
   Nestable<Infer<Head> | InferStructTuple<Tail>[number] | boolean | null>,
   null
 > {
-  return nestable(nullable(nullUnion([...structs, boolean()])));
+  return nestable(
+    nullable(
+      selectiveUnion((value) => {
+        if (typeof value === 'boolean') {
+          return boolean();
+        }
+        if (structs.length === 1) {
+          return structs[0];
+        }
+        return nullUnion(structs);
+      }),
+    ),
+  ) as unknown as Struct<
+    Nestable<Infer<Head> | InferStructTuple<Tail>[number] | boolean | null>,
+    null
+  >;
 }
 
 /**
@@ -209,7 +232,7 @@ export const InputStruct: Describe<InputElement> = element('Input', {
  */
 export const OptionStruct: Describe<OptionElement> = element('Option', {
   value: string(),
-  children: nullUnion([string()]),
+  children: string(),
 });
 
 /**
@@ -495,10 +518,13 @@ export const SectionStruct: Describe<SectionElement> = element('Section', {
  * A subset of JSX elements that are allowed as children of the Footer component.
  * This set should include a single button or a tuple of two buttons.
  */
-export const FooterChildStruct = nullUnion([
-  tuple([FooterButtonStruct, FooterButtonStruct]),
-  FooterButtonStruct,
-]);
+
+export const FooterChildStruct = selectiveUnion((value) => {
+  if (Array.isArray(value)) {
+    return tuple([FooterButtonStruct, FooterButtonStruct]);
+  }
+  return FooterButtonStruct;
+});
 
 /**
  * A struct for the {@link FooterElement} type.
@@ -548,11 +574,12 @@ export const LinkStruct: Describe<LinkElement> = element('Link', {
  */
 export const TextStruct: Describe<TextElement> = element('Text', {
   children: children([
-    string(),
-    BoldStruct,
-    ItalicStruct,
-    LinkStruct,
-    IconStruct,
+    selectiveUnion((value) => {
+      if (typeof value === 'string') {
+        return string();
+      }
+      return typedUnion([BoldStruct, ItalicStruct, LinkStruct, IconStruct]);
+    }),
   ]),
   alignment: optional(
     nullUnion([literal('start'), literal('center'), literal('end')]),
@@ -573,28 +600,36 @@ export const TextStruct: Describe<TextElement> = element('Text', {
  * A subset of JSX elements that are allowed as children of the Tooltip component.
  * This set should include all text components and the Image.
  */
-export const TooltipChildStruct = nullUnion([
-  TextStruct,
-  BoldStruct,
-  ItalicStruct,
-  LinkStruct,
-  ImageStruct,
-  IconStruct,
-  boolean(),
-]);
+export const TooltipChildStruct = selectiveUnion((value) => {
+  if (typeof value === 'boolean') {
+    return boolean();
+  }
+  return typedUnion([
+    TextStruct,
+    BoldStruct,
+    ItalicStruct,
+    LinkStruct,
+    ImageStruct,
+    IconStruct,
+  ]);
+});
 
 /**
  * A subset of JSX elements that are allowed as content of the Tooltip component.
  * This set should include all text components.
  */
-export const TooltipContentStruct = nullUnion([
-  TextStruct,
-  BoldStruct,
-  ItalicStruct,
-  LinkStruct,
-  IconStruct,
-  string(),
-]);
+export const TooltipContentStruct = selectiveUnion((value) => {
+  if (typeof value === 'string') {
+    return string();
+  }
+  return typedUnion([
+    TextStruct,
+    BoldStruct,
+    ItalicStruct,
+    LinkStruct,
+    IconStruct,
+  ]);
+});
 
 /**
  * A struct for the {@link TooltipElement} type.
@@ -609,7 +644,7 @@ export const TooltipStruct: Describe<TooltipElement> = element('Tooltip', {
  */
 export const RowStruct: Describe<RowElement> = element('Row', {
   label: string(),
-  children: nullUnion([AddressStruct, ImageStruct, TextStruct, ValueStruct]),
+  children: typedUnion([AddressStruct, ImageStruct, TextStruct, ValueStruct]),
   variant: optional(
     nullUnion([literal('default'), literal('warning'), literal('critical')]),
   ),
@@ -659,10 +694,12 @@ export const BoxChildStruct = typedUnion([
 export const ContainerStruct: Describe<ContainerElement> = element(
   'Container',
   {
-    children: nullUnion([
-      tuple([BoxChildStruct, FooterStruct]),
-      BoxChildStruct,
-    ]) as unknown as Struct<
+    children: selectiveUnion((value) => {
+      if (Array.isArray(value)) {
+        return tuple([BoxChildStruct, FooterStruct]);
+      }
+      return BoxChildStruct;
+    }) as unknown as Struct<
       [GenericSnapElement, FooterElement] | GenericSnapElement,
       null
     >,
diff --git a/packages/snaps-sdk/src/types/interface.test.ts b/packages/snaps-sdk/src/types/interface.test.ts
index 6c2a1a44e0..5f1c2ac14a 100644
--- a/packages/snaps-sdk/src/types/interface.test.ts
+++ b/packages/snaps-sdk/src/types/interface.test.ts
@@ -1,6 +1,12 @@
 import { assert } from '@metamask/superstruct';
 
-import { FormStateStruct, InterfaceStateStruct } from './interface';
+import { Text } from '../jsx';
+import { text } from '../ui';
+import {
+  ComponentOrElementStruct,
+  FormStateStruct,
+  InterfaceStateStruct,
+} from './interface';
 
 describe('FormStateStruct', () => {
   it('passes for a valid form state', () => {
@@ -15,3 +21,15 @@ describe('InterfaceStateStruct', () => {
     ).not.toThrow();
   });
 });
+
+describe('ComponentOrElementStruct', () => {
+  it('validates JSX components', () => {
+    expect(() =>
+      assert(Text({ children: 'foo' }), ComponentOrElementStruct),
+    ).not.toThrow();
+  });
+
+  it('validates legacy components', () => {
+    expect(() => assert(text('foo'), ComponentOrElementStruct)).not.toThrow();
+  });
+});
diff --git a/packages/snaps-sdk/src/types/interface.ts b/packages/snaps-sdk/src/types/interface.ts
index 86d2ed311c..3e8290cb3c 100644
--- a/packages/snaps-sdk/src/types/interface.ts
+++ b/packages/snaps-sdk/src/types/interface.ts
@@ -6,8 +6,9 @@ import {
   string,
   union,
 } from '@metamask/superstruct';
-import { JsonStruct } from '@metamask/utils';
+import { JsonStruct, hasProperty, isObject } from '@metamask/utils';
 
+import { selectiveUnion } from '../internals';
 import type { JSXElement } from '../jsx';
 import { RootJSXElementStruct } from '../jsx';
 import type { Component } from '../ui';
@@ -35,10 +36,12 @@ export type FormState = Infer<typeof FormStateStruct>;
 export type InterfaceState = Infer<typeof InterfaceStateStruct>;
 
 export type ComponentOrElement = Component | JSXElement;
-export const ComponentOrElementStruct = union([
-  ComponentStruct,
-  RootJSXElementStruct,
-]);
+export const ComponentOrElementStruct = selectiveUnion((value) => {
+  if (isObject(value) && !hasProperty(value, 'props')) {
+    return ComponentStruct;
+  }
+  return RootJSXElementStruct;
+});
 
 export const InterfaceContextStruct = record(string(), JsonStruct);
 export type InterfaceContext = Infer<typeof InterfaceContextStruct>;