diff --git a/package.json b/package.json
index 90822ba..1a2f96c 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@superindustries/language",
-  "version": "0.1.4",
-  "description": "Level 5 autonomous, self-driving API client, https://superface.ai",
+  "version": "0.2.0",
+  "description": "Superface profile and map language ASTs, https://superface.ai",
   "main": "dist/language.js",
   "source": "src/index.ts",
   "module": "dist/language.modern.js",
diff --git a/src/interfaces/ast/index.ts b/src/interfaces/ast/index.ts
index 46a701a..9199480 100644
--- a/src/interfaces/ast/index.ts
+++ b/src/interfaces/ast/index.ts
@@ -1,2 +1,3 @@
 export * from './map-ast';
 export * from './map-ast.utils';
+export * from './profile-ast';
diff --git a/src/interfaces/ast/map-ast.ts b/src/interfaces/ast/map-ast.ts
index 1cfe42b..5ffb7a8 100644
--- a/src/interfaces/ast/map-ast.ts
+++ b/src/interfaces/ast/map-ast.ts
@@ -1,3 +1,5 @@
+import { Location, Span } from './source';
+
 export type MapNodeKind =
   | 'EvalDefinition'
   | 'HTTPOperationDefinition'
@@ -16,14 +18,10 @@ export type MapNodeKind =
   | 'StepDefinition'
   | 'VariableExpressionsDefinition';
 
-export interface Location {
-  start: number;
-  end: number;
-}
-
 export interface MapASTNodeBase {
   kind: MapNodeKind;
-  loc?: Location;
+  span?: Span;
+  location?: Location;
 }
 
 export interface JSExpressionNode extends MapASTNodeBase {
@@ -111,7 +109,7 @@ export interface OperationDefinitionNode extends MapASTNodeBase {
   stepsDefinition: StepDefinitionNode[];
 }
 
-export interface ProfileIdNode extends MapASTNodeBase {
+export interface MapProfileIdNode extends MapASTNodeBase {
   kind: 'ProfileId';
   profileId: string;
 }
@@ -123,7 +121,7 @@ export interface ProviderNode extends MapASTNodeBase {
 
 export interface MapNode extends MapASTNodeBase {
   kind: 'Map';
-  profileId: ProfileIdNode;
+  profileId: MapProfileIdNode;
   provider: ProviderNode;
 }
 
@@ -154,7 +152,7 @@ export type MapASTNode =
   | OperationCallDefinitionNode
   | OperationDefinitionNode
   | OutcomeDefinitionNode
-  | ProfileIdNode
+  | MapProfileIdNode
   | ProviderNode
   | StepDefinitionNode
   | VariableExpressionDefinitionNode;
diff --git a/src/interfaces/ast/map-ast.utils.ts b/src/interfaces/ast/map-ast.utils.ts
index 251f06c..3669543 100644
--- a/src/interfaces/ast/map-ast.utils.ts
+++ b/src/interfaces/ast/map-ast.utils.ts
@@ -8,11 +8,11 @@ import {
   MapDocumentNode,
   MapExpressionDefinitionNode,
   MapNode,
+  MapProfileIdNode,
   NetworkOperationDefinitionNode,
   OperationCallDefinitionNode,
   OperationDefinitionNode,
   OutcomeDefinitionNode,
-  ProfileIdNode,
   ProviderNode,
   StepDefinitionNode,
   VariableExpressionDefinitionNode,
@@ -90,9 +90,9 @@ export function assertIsOperationDefinitionNode(
   checkNode(node, 'OperationDefinition');
 }
 
-export function assertIsProfileIdNode(
+export function assertIsMapProfileIdNode(
   node: MapASTNode
-): asserts node is ProfileIdNode {
+): asserts node is MapProfileIdNode {
   checkNode(node, 'ProfileId');
 }
 
@@ -182,7 +182,7 @@ export function isOperationDefinitionNode(
   return node.kind === 'OperationDefinition';
 }
 
-export function isProfileIdNode(node: MapASTNode): node is ProfileIdNode {
+export function isProfileIdNode(node: MapASTNode): node is MapProfileIdNode {
   return node.kind === 'ProfileId';
 }
 
diff --git a/src/interfaces/ast/profile-ast.ts b/src/interfaces/ast/profile-ast.ts
index b32b583..e154322 100644
--- a/src/interfaces/ast/profile-ast.ts
+++ b/src/interfaces/ast/profile-ast.ts
@@ -1,172 +1,234 @@
-export type ScalarTypeName = 'boolean' | 'number' | 'string';
+import { Location, Span } from './source';
 
-export interface ModelTypeName extends ProfileASTNodeBase {
-  kind: 'ModelTypeName';
-  name: string;
-}
-
-export interface ObjectModelTypeName extends ProfileASTNodeBase {
-  kind: 'ObjectModelTypeName';
-  name: string;
-}
+// BASE //
 
 export type ProfileNodeKind =
-  | 'ProfileDocument'
-  | 'Profile'
-  | 'ProfileId'
-  | 'UseCaseDefinition'
-  | 'FieldDefinition'
-  | 'ScalarModelDefinition'
+  // TYPES
+  | 'ScalarTypeName'
   | 'ObjectModelDefinition'
+  | 'FieldDefinition'
   | 'UnionModelDefinition'
   | 'EnumModelDefinition'
   | 'EnumValueDefinition'
-  | 'NamedType'
+  | 'ModelTypeName'
   | 'ListType'
   | 'NonNullType'
-  | 'ModelTypeName'
-  | 'ObjectModelTypeName';
-
-// TODO: Same as in Map AST -> reuse?
-export interface Location {
-  start: number;
-  end: number;
-}
+  // MODELS
+  | 'ScalarModelDefinition'
+  // USECASE
+  | 'UseCaseDefinition'
+  // DOCUMENT
+  | 'ProfileId'
+  | 'Profile'
+  | 'ProfileDocument';
 
-// TODO: Similar as in Map AST -> reuse?
 export interface ProfileASTNodeBase {
   kind: ProfileNodeKind;
-  loc?: Location;
-}
-
-// TODO: Same as in Map AST -> reuse?
-export interface ProfileIdNode extends ProfileASTNodeBase {
-  kind: 'ProfileId';
-  profileId: string;
+  span?: Span;
+  location?: Location;
 }
 
+/** Node preceded by documenting string literal */
 export interface DocumentedNode {
   title?: string;
   description?: string;
 }
 
-export interface ProfileNode extends ProfileASTNodeBase, DocumentedNode {
-  kind: 'Profile';
-  profileId: ProfileIdNode;
-}
+// TYPES //
 
-export interface ProfileDocumentNode extends ProfileASTNodeBase {
-  kind: 'ProfileDocument';
-  profile: ProfileNode;
-  definitions: DocumentDefinition[];
+/** From keywords: `Boolean`, `Number` and `String` */
+export interface ScalarTypeName extends ProfileASTNodeBase {
+  kind: 'ScalarTypeName';
+  name: 'boolean' | 'number' | 'string';
 }
 
-export enum ProfileUseCaseSafety {
-  safe = 'safe',
-  unsafe = 'unsafe',
-  idempotent = 'idempotent',
+/**
+ * Construct of form:
+ * `{ fields... }`
+ */
+export interface ObjectModelDefinitionNode
+  extends ProfileASTNodeBase {
+  kind: 'ObjectModelDefinition';
+  fields: FieldDefinition[];
+}
+/**
+ * Construct of form:
+ * `ident: type` or `ident`
+ * that appear inside object model definitions
+ */
+export interface FieldDefinition extends ProfileASTNodeBase, DocumentedNode {
+  kind: 'FieldDefinition';
+  fieldName: string;
+  type?: Type;
+}
+/**
+ * Construct of form:
+ * `type | type | ...`
+ */
+export interface UnionModelDefinitionNode
+  extends ProfileASTNodeBase {
+  kind: 'UnionModelDefinition';
+  types: Type[];
+}
+/**
+ * Construct of form:
+ * `enum { values... }`
+ */
+export interface EnumModelDefinitionNode
+  extends ProfileASTNodeBase {
+  kind: 'EnumModelDefinition';
+  enumValues: EnumValueDefinition[];
 }
+/**
+ * Variant of an enum definition.
+ *
+ * These are either string or number literals
+ */
+export interface EnumValueDefinition extends ProfileASTNodeBase {
+  kind: 'EnumValueDefinition';
+  enumValue: string | number | boolean;
+}
+
+export type AnonymousModelDefinitionNode =
+  | ObjectModelDefinitionNode
+  | UnionModelDefinitionNode
+  | EnumModelDefinitionNode;
 
-export interface NamedType extends ProfileASTNodeBase {
-  kind: 'NamedType';
-  type: ModelTypeName | ScalarTypeName;
+/**
+ * Name of a model type parsed from identifiers.
+ *
+ * This is the name of a user defined type.
+ */
+export interface ModelTypeName extends ProfileASTNodeBase {
+  kind: 'ModelTypeName';
+  name: string;
 }
 
+/** Array type: `[type]` */
 export interface ListType extends ProfileASTNodeBase {
   kind: 'ListType';
   type: Type;
 }
-
+/** Non-null assertion operator: `type!` */
 export interface NonNullType extends ProfileASTNodeBase {
   kind: 'NonNullType';
-  type: NamedType | ListType | AnonymousModelDefinitionNode;
+  type:
+    | ScalarTypeName
+    | ModelTypeName
+    | ListType
+    | AnonymousModelDefinitionNode;
 }
 
 export type Type =
-  | NamedType
+  | ScalarTypeName
+  | AnonymousModelDefinitionNode
+  | ModelTypeName
   | ListType
-  | NonNullType
-  | AnonymousModelDefinitionNode;
+  | NonNullType;
 
-export interface FieldDefinition extends ProfileASTNodeBase, DocumentedNode {
-  kind: 'FieldDefinition';
-  fieldName: string;
-  type: Type;
-  exampleValue?: string;
-}
-
-export interface ProfileUseCaseDefinitionNode
-  extends ProfileASTNodeBase,
-    DocumentedNode {
-  kind: 'UseCaseDefinition';
-  useCaseName: string;
-  safety: ProfileUseCaseSafety;
-  input?: ObjectModelDefinitionNode | ObjectModelTypeName;
-  result: ObjectModelDefinitionNode | ObjectModelTypeName;
-  errors?: ObjectModelTypeName[];
-}
+// MODELS //
 
+/**
+ * Construct of form:
+ * `field ident: ScalarType` or `field ident: ModelType`
+ *
+ * This is basically a type alias.
+ */
 export interface NamedScalarModelDefinitionNode
   extends ProfileASTNodeBase,
     DocumentedNode {
   kind: 'ScalarModelDefinition';
   modelName: ModelTypeName;
-  baseType: ScalarTypeName;
-}
-
-export interface ObjectModelDefinitionNode
-  extends ProfileASTNodeBase,
-    DocumentedNode {
-  kind: 'ObjectModelDefinition';
-  fields: FieldDefinition[];
+  baseType: ScalarTypeName | ModelTypeName;
 }
 
+/**
+ * Construct of form:
+ * `model ident { fields... }`
+ */
 export interface NamedObjectModelDefinitionNode
-  extends ObjectModelDefinitionNode {
-  modelName: ObjectModelTypeName;
-}
-
-export interface UnionModelDefinitionNode
-  extends ProfileASTNodeBase,
-    DocumentedNode {
-  kind: 'UnionModelDefinition';
+  extends ObjectModelDefinitionNode, DocumentedNode {
   modelName: ModelTypeName;
 }
 
+/**
+ * Construct of form:
+ * `field ident: type | type | ...`
+ */
 export interface NamedUnionModelDefinitionNode
-  extends UnionModelDefinitionNode {
+  extends UnionModelDefinitionNode, DocumentedNode {
   modelName: ModelTypeName;
 }
 
-export interface EnumModelDefinitionNode
-  extends ProfileASTNodeBase,
-    DocumentedNode {
-  kind: 'EnumModelDefinition';
-  enumValues: EnumValueDefinition[];
-}
-
-export interface NamedEnumModelDefinitionNode extends EnumModelDefinitionNode {
+/**
+ * Construct of form:
+ * `enum ident { values ... }`
+ */
+export interface NamedEnumModelDefinitionNode extends EnumModelDefinitionNode, DocumentedNode {
   modelName: ModelTypeName;
 }
 
-export interface EnumValueDefinition
-  extends ProfileASTNodeBase,
-    DocumentedNode {
-  kind: 'EnumValueDefinition';
-  enumValue: string | number;
-}
-
-export type AnonymousModelDefinitionNode =
-  | ObjectModelDefinitionNode
-  | UnionModelDefinitionNode
-  | EnumModelDefinitionNode;
-
 export type ProfileModelDefinitionNode =
   | NamedScalarModelDefinitionNode
   | NamedObjectModelDefinitionNode
   | NamedUnionModelDefinitionNode
   | NamedEnumModelDefinitionNode;
 
+// USECASE //
+
+/** Usecase safety indicator, corresponds to decorators */
+export enum ProfileUseCaseSafety {
+  safe = 'safe',
+  unsafe = 'unsafe',
+  idempotent = 'idempotent',
+}
+
+/**
+* Construct of form:
+```
+usecase ident @deco {
+  input: type
+  result: type
+  errors: [
+    type
+    type
+    ...
+  ]
+}
+```
+*/
+export interface ProfileUseCaseDefinitionNode
+  extends ProfileASTNodeBase,
+    DocumentedNode {
+  kind: 'UseCaseDefinition';
+  useCaseName: string;
+  safety: ProfileUseCaseSafety;
+  input?: Type;
+  result: Type;
+  asyncResult: boolean;
+  errors?: Type[];
+}
+
+// DOCUMENT //
+
+/** `profile: string` */
+export interface ProfileProfileIdNode extends ProfileASTNodeBase {
+  kind: 'ProfileId';
+  profileId: string;
+}
+/**
+ * The node containing document information at the top of the document.
+ */
+export interface ProfileNode extends ProfileASTNodeBase, DocumentedNode {
+  kind: 'Profile';
+  profileId: ProfileProfileIdNode;
+}
+/** Node enclosing the whole document */
+export interface ProfileDocumentNode extends ProfileASTNodeBase {
+  kind: 'ProfileDocument';
+  profile: ProfileNode;
+  definitions: DocumentDefinition[];
+}
 export type DocumentDefinition =
   | ProfileUseCaseDefinitionNode
   | ProfileModelDefinitionNode;
diff --git a/src/interfaces/ast/source.ts b/src/interfaces/ast/source.ts
new file mode 100644
index 0000000..c6183dc
--- /dev/null
+++ b/src/interfaces/ast/source.ts
@@ -0,0 +1,17 @@
+/**
+ * Human-readable location of a token inside source code.
+ * 
+ * Both `line` and `column` are indexed from 1.
+ */
+export type Location = {
+  line: number;
+  column: number;
+};
+
+/**
+ * Span of one node inside source code.
+ */
+export type Span = {
+  start: number;
+  end: number;
+};
\ No newline at end of file