diff --git a/packages/openapi-model/src/3.0.3/model/BasicNode.ts b/packages/openapi-model/src/3.0.3/model/BasicNode.ts
index 0273e558..0282b29e 100644
--- a/packages/openapi-model/src/3.0.3/model/BasicNode.ts
+++ b/packages/openapi-model/src/3.0.3/model/BasicNode.ts
@@ -12,7 +12,7 @@ export interface TreeParent {
   readonly root: OpenAPIModel;
 }
 
-export class BasicNode<TParent extends TreeParent>
+export abstract class BasicNode<TParent extends TreeParent>
   implements TreeNode<TParent>, Disposable, SpecificationExtensionsModel
 {
   readonly root: OpenAPIModel;
@@ -25,6 +25,8 @@ export class BasicNode<TParent extends TreeParent>
     this.extensions = new Map<string, JSONValue>();
   }
 
+  abstract children(): IterableIterator<TreeNode<unknown>>;
+
   // eslint-disable-next-line class-methods-use-this
   dispose(): void {}
 
diff --git a/packages/openapi-model/src/3.0.3/model/Callback.ts b/packages/openapi-model/src/3.0.3/model/Callback.ts
index f3d27fdb..b1baf8e0 100644
--- a/packages/openapi-model/src/3.0.3/model/Callback.ts
+++ b/packages/openapi-model/src/3.0.3/model/Callback.ts
@@ -5,7 +5,7 @@ import { BidiMap } from '../../BidiMap';
 import { BasicNode } from './BasicNode';
 import { PathItem } from './PathItem';
 
-import type { CallbackModel, CallbackModelParent, PathItemModel } from './types';
+import type { CallbackModel, CallbackModelParent, PathItemModel, TreeNode } from './types';
 import type { ParametrisedURLString } from '@fresha/api-tools-core';
 
 /**
@@ -19,6 +19,10 @@ export class Callback extends BasicNode<CallbackModelParent> implements Callback
     this.paths = new BidiMap<ParametrisedURLString, PathItemModel>();
   }
 
+  children(): IterableIterator<TreeNode<unknown>> {
+    return this.paths.values();
+  }
+
   getItemUrl(pathItem: PathItemModel): string | undefined {
     return this.paths.getKey(pathItem);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Components.ts b/packages/openapi-model/src/3.0.3/model/Components.ts
index 956eb2a9..9bf5c247 100644
--- a/packages/openapi-model/src/3.0.3/model/Components.ts
+++ b/packages/openapi-model/src/3.0.3/model/Components.ts
@@ -29,6 +29,7 @@ import type {
   CreateSchemaOptions,
   SchemaModel,
   SecuritySchemaModel,
+  TreeNode,
 } from './types';
 import type { CommonMarkString } from '@fresha/api-tools-core';
 
@@ -59,6 +60,36 @@ export class Components extends BasicNode<ComponentsModelParent> implements Comp
     this.callbacks = new Map<string, CallbackModel>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    for (const schema of this.schemas.values()) {
+      yield schema;
+    }
+    for (const response of this.responses.values()) {
+      yield response;
+    }
+    for (const parameter of this.parameters.values()) {
+      yield parameter;
+    }
+    for (const example of this.examples.values()) {
+      yield example;
+    }
+    for (const requestBody of this.requestBodies.values()) {
+      yield requestBody;
+    }
+    for (const header of this.headers.values()) {
+      yield header;
+    }
+    for (const securitySchema of this.securitySchemes.values()) {
+      yield securitySchema;
+    }
+    for (const link of this.links.values()) {
+      yield link;
+    }
+    for (const callback of this.callbacks.values()) {
+      yield callback;
+    }
+  }
+
   isEmpty(): boolean {
     return (
       !this.schemas.size &&
diff --git a/packages/openapi-model/src/3.0.3/model/Contact.ts b/packages/openapi-model/src/3.0.3/model/Contact.ts
index 0714f06b..6cd45d23 100644
--- a/packages/openapi-model/src/3.0.3/model/Contact.ts
+++ b/packages/openapi-model/src/3.0.3/model/Contact.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { ContactModel, ContactModelParent } from './types';
+import type { ContactModel, ContactModelParent, TreeNode } from './types';
 import type { Nullable, URLString, EmailString } from '@fresha/api-tools-core';
 
 /**
@@ -17,4 +17,8 @@ export class Contact extends BasicNode<ContactModelParent> implements ContactMod
     this.url = null;
     this.email = null;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/Discriminator.ts b/packages/openapi-model/src/3.0.3/model/Discriminator.ts
index 2eee8156..42db4c3c 100644
--- a/packages/openapi-model/src/3.0.3/model/Discriminator.ts
+++ b/packages/openapi-model/src/3.0.3/model/Discriminator.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { DiscriminatorModel, DiscriminatorModelParent } from './types';
+import type { DiscriminatorModel, DiscriminatorModelParent, TreeNode } from './types';
 
 /**
  * @see http://spec.openapis.org/oas/v3.0.3#discriminator-object
@@ -17,4 +17,8 @@ export class Discriminator
     this.propertyName = propertyName;
     this.mapping = new Map<string, string>();
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/Encoding.ts b/packages/openapi-model/src/3.0.3/model/Encoding.ts
index b9cb84b2..0a8f1684 100644
--- a/packages/openapi-model/src/3.0.3/model/Encoding.ts
+++ b/packages/openapi-model/src/3.0.3/model/Encoding.ts
@@ -8,6 +8,7 @@ import type {
   EncodingModelParent,
   EncodingSerializationStyle,
   HeaderModel,
+  TreeNode,
 } from './types';
 import type { Nullable } from '@fresha/api-tools-core';
 
@@ -30,6 +31,10 @@ export class Encoding extends BasicNode<EncodingModelParent> implements Encoding
     this.allowReserved = false;
   }
 
+  children(): IterableIterator<TreeNode<unknown>> {
+    return this.headers.values();
+  }
+
   getHeader(name: string): HeaderModel | undefined {
     return this.headers.get(name);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Example.ts b/packages/openapi-model/src/3.0.3/model/Example.ts
index 2e35542c..14cf3386 100644
--- a/packages/openapi-model/src/3.0.3/model/Example.ts
+++ b/packages/openapi-model/src/3.0.3/model/Example.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { ExampleModel, ExampleModelParent } from './types';
+import type { ExampleModel, ExampleModelParent, TreeNode } from './types';
 import type { Nullable, URLString, JSONValue } from '@fresha/api-tools-core';
 
 /**
@@ -19,4 +19,9 @@ export class Example extends BasicNode<ExampleModelParent> implements ExampleMod
     this.value = null;
     this.externalValue = null;
   }
+
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/ExternalDocumentation.ts b/packages/openapi-model/src/3.0.3/model/ExternalDocumentation.ts
index a4e86b4a..faa755aa 100644
--- a/packages/openapi-model/src/3.0.3/model/ExternalDocumentation.ts
+++ b/packages/openapi-model/src/3.0.3/model/ExternalDocumentation.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { ExternalDocumentationModel, ExternalDocumentationModelParent } from './types';
+import type { ExternalDocumentationModel, ExternalDocumentationModelParent, TreeNode } from './types';
 import type { CommonMarkString, Nullable, URLString } from '@fresha/api-tools-core';
 
 /**
@@ -18,4 +18,8 @@ export class ExternalDocumentation
     this.url = url;
     this.description = null;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/Header.ts b/packages/openapi-model/src/3.0.3/model/Header.ts
index cd5adfdb..bd84b46e 100644
--- a/packages/openapi-model/src/3.0.3/model/Header.ts
+++ b/packages/openapi-model/src/3.0.3/model/Header.ts
@@ -11,6 +11,7 @@ import type {
   HeaderParameterSerializationStyle,
   MediaTypeModel,
   SchemaModel,
+  TreeNode,
 } from './types';
 import type { Nullable, JSONValue, MIMETypeString, CommonMarkString } from '@fresha/api-tools-core';
 
@@ -41,6 +42,18 @@ export class Header extends BasicNode<HeaderModelParent> implements HeaderModel
     this.content = new Map<MIMETypeString, MediaTypeModel>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    if (this.schema) {
+      yield this.schema;
+    }
+    for (const example of this.examples.values()) {
+      yield example;
+    }
+    for (const mediaType of this.content.values()) {
+      yield mediaType;
+    }
+  }
+
   getExample(name: string): ExampleModel | undefined {
     return this.examples.get(name);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Info.ts b/packages/openapi-model/src/3.0.3/model/Info.ts
index de183701..96cec493 100644
--- a/packages/openapi-model/src/3.0.3/model/Info.ts
+++ b/packages/openapi-model/src/3.0.3/model/Info.ts
@@ -2,7 +2,7 @@ import { BasicNode } from './BasicNode';
 import { Contact } from './Contact';
 import { License } from './License';
 
-import type { InfoModel, InfoModelParent } from './types';
+import type { InfoModel, InfoModelParent, TreeNode } from './types';
 import type { CommonMarkString, Nullable, URLString, VersionString } from '@fresha/api-tools-core';
 
 /**
@@ -25,4 +25,9 @@ export class Info extends BasicNode<InfoModelParent> implements InfoModel {
     this.license = new License(this, 'UNLICENSED');
     this.version = version;
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+    yield this.contact;
+    yield this.license;
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/License.ts b/packages/openapi-model/src/3.0.3/model/License.ts
index e60dbb8b..0975e384 100644
--- a/packages/openapi-model/src/3.0.3/model/License.ts
+++ b/packages/openapi-model/src/3.0.3/model/License.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { LicenseModel, LicenseModelParent } from './types';
+import type { LicenseModel, LicenseModelParent, TreeNode } from './types';
 import type { Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -15,4 +15,7 @@ export class License extends BasicNode<LicenseModelParent> implements LicenseMod
     this.name = name;
     this.url = null;
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/Link.ts b/packages/openapi-model/src/3.0.3/model/Link.ts
index 352e692e..67aabec9 100644
--- a/packages/openapi-model/src/3.0.3/model/Link.ts
+++ b/packages/openapi-model/src/3.0.3/model/Link.ts
@@ -3,7 +3,7 @@ import assert from 'assert';
 import { BasicNode } from './BasicNode';
 
 import type { Server } from './Server';
-import type { LinkModel, LinkModelParent } from './types';
+import type { LinkModel, LinkModelParent, TreeNode } from './types';
 import type { Nullable, JSONValue } from '@fresha/api-tools-core';
 
 /**
@@ -27,6 +27,9 @@ export class Link extends BasicNode<LinkModelParent> implements LinkModel {
     this.server = null;
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
+
   getParameter(key: string): JSONValue | undefined {
     return this.parameters.get(key);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/MediaType.ts b/packages/openapi-model/src/3.0.3/model/MediaType.ts
index 75f52ded..7a96c07b 100644
--- a/packages/openapi-model/src/3.0.3/model/MediaType.ts
+++ b/packages/openapi-model/src/3.0.3/model/MediaType.ts
@@ -12,6 +12,7 @@ import type {
   MediaTypeModelParent,
   CreateOrSetSchemaOptions,
   SchemaModel,
+  TreeNode,
 } from './types';
 import type { Nullable, JSONValue } from '@fresha/api-tools-core';
 
@@ -32,6 +33,18 @@ export class MediaType extends BasicNode<MediaTypeModelParent> implements MediaT
     this.encoding = new Map<string, EncodingModel>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    if (this.schema) {
+      yield this.schema;
+    }
+    for (const example of this.examples.values()) {
+      yield example;
+    }
+    for (const encoding of this.encoding.values()) {
+      yield encoding;
+    }
+  }
+
   setSchema(options: CreateOrSetSchemaOptions): SchemaModel {
     const result = SchemaFactory.createOrGet(this, options);
     this.schema = result;
diff --git a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthAuthorisationCodeFlow.ts b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthAuthorisationCodeFlow.ts
index df53028d..e064b58c 100644
--- a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthAuthorisationCodeFlow.ts
+++ b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthAuthorisationCodeFlow.ts
@@ -1,6 +1,6 @@
 import { OAuthFlowBase } from './OAuthFlowBase';
 
-import type { OAuthAuthorizationCodeFlowModel, OAuthFlowModelParent } from '../types';
+import type { OAuthAuthorizationCodeFlowModel, OAuthFlowModelParent, TreeNode } from '../types';
 import type { URLString } from '@fresha/api-tools-core';
 
 /**
@@ -19,4 +19,9 @@ export class OAuthAuthorisationCodeFlow
     this.authorizationUrl = authorizationUrl;
     this.tokenUrl = tokenUrl;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthClientCredentialsFlow.ts b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthClientCredentialsFlow.ts
index 3ed6ada2..720b2b9d 100644
--- a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthClientCredentialsFlow.ts
+++ b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthClientCredentialsFlow.ts
@@ -1,6 +1,6 @@
 import { OAuthFlowBase } from './OAuthFlowBase';
 
-import type { OAuthClientCredentialsFlowModel, OAuthFlowModelParent } from '../types';
+import type { OAuthClientCredentialsFlowModel, OAuthFlowModelParent, TreeNode } from '../types';
 import type { URLString } from '@fresha/api-tools-core';
 
 /**
@@ -17,4 +17,9 @@ export class OAuthClientCredentialsFlow
     super(parent, 'clientCredentials');
     this.tokenUrl = tokenUrl;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthFlows.ts b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthFlows.ts
index ebb53cc9..f0c908ef 100644
--- a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthFlows.ts
+++ b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthFlows.ts
@@ -7,6 +7,7 @@ import type {
   OAuthFlowsModelParent,
   OAuthImplicitFlowModel,
   OAuthPasswordFlowModel,
+  TreeNode,
 } from '../types';
 import type { Nullable } from '@fresha/api-tools-core';
 
@@ -26,4 +27,19 @@ export class OAuthFlows extends BasicNode<OAuthFlowsModelParent> implements OAut
     this.clientCredentials = null;
     this.authorizationCode = null;
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+      if (this.implicit) {
+        yield this.implicit;
+      }
+      if (this.password) {
+        yield this.password;
+      }
+      if (this.clientCredentials) {
+        yield this.clientCredentials;
+      }
+      if (this.authorizationCode) {
+        yield this.authorizationCode;
+      }
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthImplicitFlow.ts b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthImplicitFlow.ts
index 036e3a2c..bd75952c 100644
--- a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthImplicitFlow.ts
+++ b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthImplicitFlow.ts
@@ -1,6 +1,6 @@
 import { OAuthFlowBase } from './OAuthFlowBase';
 
-import type { OAuthFlowModelParent, OAuthImplicitFlowModel } from '../types';
+import type { OAuthFlowModelParent, OAuthImplicitFlowModel, TreeNode } from '../types';
 import type { URLString } from '@fresha/api-tools-core';
 
 /**
@@ -14,4 +14,9 @@ export class OAuthImplicitFlow extends OAuthFlowBase implements OAuthImplicitFlo
     super(parent, 'implicit');
     this.authorizationUrl = authorizationUrl;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthPasswordFlow.ts b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthPasswordFlow.ts
index 99720e76..eddf32da 100644
--- a/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthPasswordFlow.ts
+++ b/packages/openapi-model/src/3.0.3/model/OAuthFlow/OAuthPasswordFlow.ts
@@ -1,6 +1,6 @@
 import { OAuthFlowBase } from './OAuthFlowBase';
 
-import type { OAuthFlowModelParent, OAuthPasswordFlowModel } from '../types';
+import type { OAuthFlowModelParent, OAuthPasswordFlowModel, TreeNode } from '../types';
 import type { URLString } from '@fresha/api-tools-core';
 
 /**
@@ -14,4 +14,9 @@ export class OAuthPasswordFlow extends OAuthFlowBase implements OAuthPasswordFlo
     super(parent, 'password');
     this.tokenUrl = tokenUrl;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/OpenAPI.ts b/packages/openapi-model/src/3.0.3/model/OpenAPI.ts
index e8aad1a0..0c542d76 100644
--- a/packages/openapi-model/src/3.0.3/model/OpenAPI.ts
+++ b/packages/openapi-model/src/3.0.3/model/OpenAPI.ts
@@ -18,6 +18,7 @@ import type {
   SpecificationExtensionsModel,
   OpenAPIModelFactory,
   SecurityRequirementModel,
+  TreeNode,
 } from './types';
 import type {
   CommonMarkString,
@@ -59,6 +60,24 @@ export class OpenAPI implements OpenAPIModel, SpecificationExtensionsModel {
     this.extensions = new Map<string, JSONValue>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    yield this.info;
+    for (const server of this.servers) {
+      yield server;
+    }
+    yield this.paths;
+    yield this.components;
+    for (const security of this.security) {
+      yield security;
+    }
+    for (const tag of this.tags) {
+      yield tag;
+    }
+    if (this.externalDocs) {
+      yield this.externalDocs;
+    }
+  }
+
   get root(): OpenAPIModel {
     return this;
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Operation.ts b/packages/openapi-model/src/3.0.3/model/Operation.ts
index 3c4973ee..3f0a08c7 100644
--- a/packages/openapi-model/src/3.0.3/model/Operation.ts
+++ b/packages/openapi-model/src/3.0.3/model/Operation.ts
@@ -21,6 +21,7 @@ import type {
   ResponseModel,
   SecurityRequirementModel,
   ServerModel,
+  TreeNode,
 } from './types';
 import type { CommonMarkString, Nullable, ParametrisedURLString } from '@fresha/api-tools-core';
 
@@ -57,6 +58,30 @@ export class Operation extends BasicNode<OperationModelParent> implements Operat
     this.servers = [];
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    if (this.externalDocumentation) {
+      yield this.externalDocumentation;
+    }
+    for (const parameter of this.parameters) {
+      yield parameter;
+    }
+    if (this.requestBody) {
+      yield this.requestBody;
+    }
+    yield this.responses;
+    for (const callback of this.callbacks.values()) {
+      yield callback;
+    }
+    if (this.security) {
+      for (const security of this.security) {
+        yield security;
+      }
+    }
+    for (const server of this.servers) {
+      yield server;
+    }
+  }
+
   get httpMethod(): PathItemOperationKey {
     return this.parent.getOperationKeyOrThrow(this);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Parameter/ParameterBase.ts b/packages/openapi-model/src/3.0.3/model/Parameter/ParameterBase.ts
index 85e77db5..7b3094b9 100644
--- a/packages/openapi-model/src/3.0.3/model/Parameter/ParameterBase.ts
+++ b/packages/openapi-model/src/3.0.3/model/Parameter/ParameterBase.ts
@@ -12,6 +12,7 @@ import type {
   ParameterLocation,
   ParameterModelParent,
   SchemaModel,
+  TreeNode,
 } from '../types';
 import type { JSONValue, MIMETypeString, Nullable } from '@fresha/api-tools-core';
 
@@ -42,6 +43,18 @@ export abstract class ParameterBase extends BasicNode<ParameterModelParent> {
     this.required = false;
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    if (this.schema) {
+      yield this.schema;
+    }
+    for (const mediaType of this.content.values()) {
+      yield mediaType;
+    }
+    for (const example of this.examples.values()) {
+      yield example;
+    }
+  }
+
   getExample(name: string): ExampleModel | undefined {
     return this.examples.get(name);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/PathItem.ts b/packages/openapi-model/src/3.0.3/model/PathItem.ts
index 6948b343..0c312236 100644
--- a/packages/openapi-model/src/3.0.3/model/PathItem.ts
+++ b/packages/openapi-model/src/3.0.3/model/PathItem.ts
@@ -13,6 +13,7 @@ import type {
   PathItemModelParent,
   ParameterModel,
   ServerModel,
+  TreeNode,
 } from './types';
 import type { Nullable, ParametrisedURLString } from '@fresha/api-tools-core';
 
@@ -35,6 +36,12 @@ export class PathItem extends BasicNode<PathItemModelParent> implements PathItem
     this.parameters = [];
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    for (const [, operation] of this.operations()) {
+      yield operation;
+    }
+  }
+
   get pathUrl(): ParametrisedURLString {
     return this.parent.getItemUrlOrThrow(this);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Paths.ts b/packages/openapi-model/src/3.0.3/model/Paths.ts
index 8405de8d..85bf42f6 100644
--- a/packages/openapi-model/src/3.0.3/model/Paths.ts
+++ b/packages/openapi-model/src/3.0.3/model/Paths.ts
@@ -4,7 +4,7 @@ import { BidiMap } from '../../BidiMap';
 
 import { BasicNode } from './BasicNode';
 
-import type { PathItemModel, PathsModel, PathsModelParent } from './types';
+import type { PathItemModel, PathsModel, PathsModelParent, TreeNode } from './types';
 import type { ParametrisedURLString } from '@fresha/api-tools-core';
 
 /**
@@ -18,6 +18,10 @@ export class Paths extends BasicNode<PathsModelParent> implements PathsModel {
     this.items = new BidiMap<ParametrisedURLString, PathItemModel>();
   }
 
+  children(): IterableIterator<TreeNode<unknown>> {
+    return this.items.values();
+  }
+
   getItem(url: ParametrisedURLString): PathItemModel | undefined {
     return this.items.get(url);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/RequestBody.ts b/packages/openapi-model/src/3.0.3/model/RequestBody.ts
index c3750051..78439e2c 100644
--- a/packages/openapi-model/src/3.0.3/model/RequestBody.ts
+++ b/packages/openapi-model/src/3.0.3/model/RequestBody.ts
@@ -3,7 +3,7 @@ import assert from 'assert';
 import { BasicNode } from './BasicNode';
 import { MediaType } from './MediaType';
 
-import type { MediaTypeModel, RequestBodyModel, RequestBodyModelParent } from './types';
+import type { MediaTypeModel, RequestBodyModel, RequestBodyModelParent, TreeNode } from './types';
 import type { MIMETypeString, Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -21,6 +21,10 @@ export class RequestBody extends BasicNode<RequestBodyModelParent> implements Re
     this.required = false;
   }
 
+  children(): IterableIterator<TreeNode<unknown>> {
+      return this.content.values();
+  }
+
   getContent(mimeType: MIMETypeString): MediaTypeModel | undefined {
     return this.content.get(mimeType);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Response.ts b/packages/openapi-model/src/3.0.3/model/Response.ts
index c1ac9fd4..d5da5ee0 100644
--- a/packages/openapi-model/src/3.0.3/model/Response.ts
+++ b/packages/openapi-model/src/3.0.3/model/Response.ts
@@ -11,6 +11,7 @@ import type {
   MediaTypeModel,
   ResponseModel,
   ResponseModelParent,
+  TreeNode,
 } from './types';
 import type { MIMETypeString } from '@fresha/api-tools-core';
 
@@ -31,6 +32,18 @@ export class Response extends BasicNode<ResponseModelParent> implements Response
     this.links = new Map<string, LinkModel>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+      for (const header of this.headers.values()) {
+        yield header
+      }
+      for (const content of this.content.values()) {
+        yield content;
+      }
+      for (const link of this.links.values()) {
+        yield link;
+      }
+  }
+
   getHeader(name: string): HeaderModel | undefined {
     return this.headers.get(name);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/Responses.ts b/packages/openapi-model/src/3.0.3/model/Responses.ts
index 2c403d8d..fb0c1b31 100644
--- a/packages/openapi-model/src/3.0.3/model/Responses.ts
+++ b/packages/openapi-model/src/3.0.3/model/Responses.ts
@@ -3,7 +3,7 @@ import assert from 'assert';
 import { BasicNode } from './BasicNode';
 import { Response } from './Response';
 
-import type { HTTPStatusCode, ResponseModel, ResponsesModel, ResponsesModelParent } from './types';
+import type { HTTPStatusCode, ResponseModel, ResponsesModel, ResponsesModelParent, TreeNode } from './types';
 import type { CommonMarkString, Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -19,6 +19,15 @@ export class Responses extends BasicNode<ResponsesModelParent> implements Respon
     this.codes = new Map<HTTPStatusCode, ResponseModel>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+      if (this.default) {
+        yield this.default;
+      }
+      for (const response of this.codes.values()) {
+        yield response;
+      }
+  }
+
   setDefaultResponse(description: string): ResponseModel {
     const response = new Response(this, description);
     this.default = response;
diff --git a/packages/openapi-model/src/3.0.3/model/Schema.ts b/packages/openapi-model/src/3.0.3/model/Schema.ts
index 214f2f22..b3956cc1 100644
--- a/packages/openapi-model/src/3.0.3/model/Schema.ts
+++ b/packages/openapi-model/src/3.0.3/model/Schema.ts
@@ -17,6 +17,7 @@ import type {
   SchemaPropertyObject,
   SchemaType,
   XMLModel,
+  TreeNode,
 } from './types';
 import type { CommonMarkString, JSONValue, Nullable } from '@fresha/api-tools-core';
 
@@ -301,6 +302,39 @@ export class Schema extends BasicNode<SchemaModelParent> implements SchemaModel
     this.deprecated = false;
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+    for (const alt of this.allOf) {
+      yield alt;
+    }
+    for (const alt of this.oneOf) {
+      yield alt;
+    }
+    for (const alt of this.anyOf) {
+      yield alt;
+    }
+    if (this.not) {
+      yield this.not;
+    }
+    if (this.items) {
+      yield this.items;
+    }
+    for (const prop of this.properties.values()) {
+      yield prop;
+    }
+    if (this.additionalProperties && typeof this.additionalProperties !== 'boolean') {
+      yield this.additionalProperties;
+    }
+    if (this.discriminator) {
+      yield this.discriminator;
+    }
+    if (this.xml) {
+      yield this.xml;
+    }
+    if (this.externalDocs) {
+      yield this.externalDocs;
+    }
+  }
+
   isComposite(): boolean {
     return !!(this.allOf.length || this.oneOf.length || this.anyOf.length);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/SecurityRequirement.ts b/packages/openapi-model/src/3.0.3/model/SecurityRequirement.ts
index bc186116..021cecf9 100644
--- a/packages/openapi-model/src/3.0.3/model/SecurityRequirement.ts
+++ b/packages/openapi-model/src/3.0.3/model/SecurityRequirement.ts
@@ -2,7 +2,7 @@ import assert from 'assert';
 
 import { BasicNode } from './BasicNode';
 
-import type { SecurityRequirementModel, SecurityRequirementModelParent } from './types';
+import type { SecurityRequirementModel, SecurityRequirementModelParent, TreeNode } from './types';
 
 /**
  * @see http://spec.openapis.org/oas/v3.0.3#security-requirement-object
@@ -18,6 +18,9 @@ export class SecurityRequirement
     this.scopes = new Map<string, string[]>();
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+  }
+
   getScopes(schemeName: string): string[] | undefined {
     return this.scopes.get(schemeName);
   }
diff --git a/packages/openapi-model/src/3.0.3/model/SecurityScheme/APIKeySecurityScheme.ts b/packages/openapi-model/src/3.0.3/model/SecurityScheme/APIKeySecurityScheme.ts
index 7a304c9f..01cb7eb3 100644
--- a/packages/openapi-model/src/3.0.3/model/SecurityScheme/APIKeySecurityScheme.ts
+++ b/packages/openapi-model/src/3.0.3/model/SecurityScheme/APIKeySecurityScheme.ts
@@ -1,6 +1,6 @@
 import { SecuritySchemeBase } from './SecuritySchemeBase';
 
-import type { APIKeySecuritySchemaModel, SecuritySchemaModelParent } from '../types';
+import type { APIKeySecuritySchemaModel, SecuritySchemaModelParent, TreeNode } from '../types';
 
 /**
  * @see http://spec.openapis.org/oas/v3.0.3#security-scheme-object
@@ -19,4 +19,9 @@ export class APIKeySecurityScheme extends SecuritySchemeBase implements APIKeySe
     this.name = name;
     this.in = location;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/SecurityScheme/HTTPSecurityScheme.ts b/packages/openapi-model/src/3.0.3/model/SecurityScheme/HTTPSecurityScheme.ts
index 6527bb38..c9f192ef 100644
--- a/packages/openapi-model/src/3.0.3/model/SecurityScheme/HTTPSecurityScheme.ts
+++ b/packages/openapi-model/src/3.0.3/model/SecurityScheme/HTTPSecurityScheme.ts
@@ -2,7 +2,7 @@ import { Schema, SchemaFactory } from '../Schema';
 
 import { SecuritySchemeBase } from './SecuritySchemeBase';
 
-import type { HTTPSecuritySchemaModel, SchemaModel, SecuritySchemaModelParent } from '../types';
+import type { HTTPSecuritySchemaModel, SchemaModel, SecuritySchemaModelParent, TreeNode } from '../types';
 import type { Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -18,4 +18,9 @@ export class HTTPSecurityScheme extends SecuritySchemeBase implements HTTPSecuri
     this.scheme = scheme ?? SchemaFactory.create(this, null);
     this.bearerFormat = null;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/SecurityScheme/OAuth2SecurityScheme.ts b/packages/openapi-model/src/3.0.3/model/SecurityScheme/OAuth2SecurityScheme.ts
index bc8abb5e..35094e65 100644
--- a/packages/openapi-model/src/3.0.3/model/SecurityScheme/OAuth2SecurityScheme.ts
+++ b/packages/openapi-model/src/3.0.3/model/SecurityScheme/OAuth2SecurityScheme.ts
@@ -2,7 +2,7 @@ import { OAuthFlows } from '../OAuthFlow';
 
 import { SecuritySchemeBase } from './SecuritySchemeBase';
 
-import type { OAuth2SecuritySchemaModel, SecuritySchemaModelParent } from '../types';
+import type { OAuth2SecuritySchemaModel, SecuritySchemaModelParent, TreeNode } from '../types';
 
 /**
  * @see http://spec.openapis.org/oas/v3.0.3#security-scheme-object
@@ -15,4 +15,8 @@ export class OAuth2SecurityScheme extends SecuritySchemeBase implements OAuth2Se
     super(parent, 'oauth2');
     this.flows = new OAuthFlows(this);
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+    yield this.flows;
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/SecurityScheme/OpenIdConnectSecurityScheme.ts b/packages/openapi-model/src/3.0.3/model/SecurityScheme/OpenIdConnectSecurityScheme.ts
index 7b529aa9..49e584cd 100644
--- a/packages/openapi-model/src/3.0.3/model/SecurityScheme/OpenIdConnectSecurityScheme.ts
+++ b/packages/openapi-model/src/3.0.3/model/SecurityScheme/OpenIdConnectSecurityScheme.ts
@@ -1,6 +1,6 @@
 import { SecuritySchemeBase } from './SecuritySchemeBase';
 
-import type { OpenIDConnectSecuritySchemaModel, SecuritySchemaModelParent } from '../types';
+import type { OpenIDConnectSecuritySchemaModel, SecuritySchemaModelParent, TreeNode } from '../types';
 import type { URLString } from '@fresha/api-tools-core';
 
 /**
@@ -17,4 +17,9 @@ export class OpenIdConnectSecurityScheme
     super(parent, 'openIdConnect');
     this.openIdConnectUrl = openIdConnectUrl;
   }
+
+  // eslint-disable-next-line class-methods-use-this
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/Server.ts b/packages/openapi-model/src/3.0.3/model/Server.ts
index 8940ee96..497592f2 100644
--- a/packages/openapi-model/src/3.0.3/model/Server.ts
+++ b/packages/openapi-model/src/3.0.3/model/Server.ts
@@ -3,7 +3,7 @@ import assert from 'assert';
 import { BasicNode } from './BasicNode';
 import { ServerVariable } from './ServerVariable';
 
-import type { ServerModel, ServerModelParent, ServerVariableModel } from './types';
+import type { ServerModel, ServerModelParent, ServerVariableModel, TreeNode } from './types';
 import type { Nullable } from '@fresha/api-tools-core';
 
 const isValidVariableName = (str: string): boolean => !!str;
@@ -31,6 +31,10 @@ export class Server extends BasicNode<ServerModelParent> implements ServerModel
     }
   }
 
+  children(): IterableIterator<TreeNode<unknown>> {
+    return this.mVariables.values();
+  }
+
   get url(): string {
     return this.mUrl;
   }
diff --git a/packages/openapi-model/src/3.0.3/model/ServerVariable.ts b/packages/openapi-model/src/3.0.3/model/ServerVariable.ts
index 76674577..de55271c 100644
--- a/packages/openapi-model/src/3.0.3/model/ServerVariable.ts
+++ b/packages/openapi-model/src/3.0.3/model/ServerVariable.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { ServerVariableModel, ServerVariableModelParent } from './types';
+import type { ServerVariableModel, ServerVariableModelParent, TreeNode } from './types';
 import type { Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -21,6 +21,10 @@ export class ServerVariable
     this.description = null;
   }
 
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
+
   addEnum(...values: string[]): void {
     for (const value of values) {
       this.enum.add(value);
diff --git a/packages/openapi-model/src/3.0.3/model/Tag.ts b/packages/openapi-model/src/3.0.3/model/Tag.ts
index dd740603..2d3f6fd8 100644
--- a/packages/openapi-model/src/3.0.3/model/Tag.ts
+++ b/packages/openapi-model/src/3.0.3/model/Tag.ts
@@ -2,7 +2,7 @@ import { CommonMarkString, Nullable } from '@fresha/api-tools-core';
 
 import { BasicNode } from './BasicNode';
 
-import type { ExternalDocumentationModel, TagModel, TagModelParent } from './types';
+import type { ExternalDocumentationModel, TagModel, TagModelParent, TreeNode } from './types';
 
 /**
  * @see http://spec.openapis.org/oas/v3.0.3#tag-object
@@ -18,4 +18,10 @@ export class Tag extends BasicNode<TagModelParent> implements TagModel {
     this.description = null;
     this.externalDocs = null;
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+    if (this.externalDocs) {
+      yield this.externalDocs;
+    }
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/TreeNodeVisitor.test.ts b/packages/openapi-model/src/3.0.3/model/TreeNodeVisitor.test.ts
new file mode 100644
index 00000000..78fba80d
--- /dev/null
+++ b/packages/openapi-model/src/3.0.3/model/TreeNodeVisitor.test.ts
@@ -0,0 +1,35 @@
+import fs from 'fs';
+import path from 'path';
+
+import yaml from 'yaml';
+
+import { OpenAPIReader } from './OpenAPIReader';
+
+import type { OpenAPIObject } from '../types';
+import { TreeNode } from './types';
+
+const lines: string[] = [];
+
+const visit = (obj: { children: () => IterableIterator<TreeNode<unknown>>; }, indent: number = 0): void => {
+  lines.push(`${obj.constructor.name}`.padStart(indent));
+  for (const child of obj.children()) {
+    visit(child, indent + 2);
+  }
+};
+
+test('example api',
+  () => {
+    const reader = new OpenAPIReader();
+
+    const inputText = fs.readFileSync(
+      path.join(__dirname, '..', '..', '..', 'examples', 'json-api.yaml'),
+      'utf-8',
+    );
+    const inputData = yaml.parse(inputText) as OpenAPIObject;
+
+    const openapi = reader.parse(inputData);
+    visit(openapi);
+
+    global.console.log(lines.join('\n'));
+  },
+);
diff --git a/packages/openapi-model/src/3.0.3/model/XML.ts b/packages/openapi-model/src/3.0.3/model/XML.ts
index 784b9936..903b5557 100644
--- a/packages/openapi-model/src/3.0.3/model/XML.ts
+++ b/packages/openapi-model/src/3.0.3/model/XML.ts
@@ -1,6 +1,6 @@
 import { BasicNode } from './BasicNode';
 
-import type { XMLModel, XMLModelParent } from './types';
+import type { TreeNode, XMLModel, XMLModelParent } from './types';
 import type { Nullable } from '@fresha/api-tools-core';
 
 /**
@@ -21,4 +21,8 @@ export class XML extends BasicNode<XMLModelParent> implements XMLModel {
     this.attribute = false;
     this.wrapped = false;
   }
+
+  *children(): IterableIterator<TreeNode<unknown>> {
+
+  }
 }
diff --git a/packages/openapi-model/src/3.0.3/model/types.ts b/packages/openapi-model/src/3.0.3/model/types.ts
index d1578a50..3ca057bf 100644
--- a/packages/openapi-model/src/3.0.3/model/types.ts
+++ b/packages/openapi-model/src/3.0.3/model/types.ts
@@ -35,6 +35,8 @@ export type ExtensionFields = Map<string, JSONValue>;
 export interface TreeNode<TParent> extends Disposable {
   readonly root: OpenAPIModel;
   readonly parent: TParent;
+
+  children(): IterableIterator<TreeNode<unknown>>;
 }
 
 /**
@@ -1145,6 +1147,8 @@ export interface OpenAPIModel extends Disposable, SpecificationExtensionsModel {
   readonly tags: ReadonlyArray<TagModel>;
   readonly externalDocs: Nullable<ExternalDocumentationModel>;
 
+  children(): IterableIterator<TreeNode<unknown>>;
+
   getServer(url: ParametrisedURLString): ServerModel | undefined;
   getServerOrThrow(url: ParametrisedURLString): ServerModel;
   addServer(