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docs/types/typeguard.md

@@ -0,0 +1,17 @@
+[Overview](../overview.md) | [Installation](../installation.md) | [Usage](../usage.md) | **Types** | [Values](../values/) | [Syntax](../syntax/) | [TypeRegistry](../type-registry.md) | [TypeCheck](../type-check.md)
+
+# TypeGuard
+
+TypeBox can check its own types with the TypeGuard module. This module is written for type introspection and provides structural tests for every built-in TypeBox type. Functions of this module return `is` guards which can be used with control flow assertions to obtain schema inference for unknown values. The following guards that the value `T` is TString.
+
+```typescript
+import { TypeGuard, Kind } from "@alkdev/typebox";
+
+const T = { [Kind]: "String", type: "string" };
+
+if (TypeGuard.IsString(T)) {
+  // T is TString
+}
+```
+
+Back to [Home](../../readme.md)