docs: add jwt string validator

README.md

@@ -53,7 +53,6 @@
 <!-- <hr/> -->
 <br/>
 <br/>
-
 ## Table of contents
 
 > These docs have been translated into [Chinese](./README_ZH.md) and [Korean](./README_KO.md).
@@ -88,6 +87,7 @@
   - [Times](#times)
   - [IP addresses](#ip-addresses)
   - [IP ranges](#ip-ranges-cidr)
+  - [JWTs](#jwts)
 - [Numbers](#numbers)
 - [BigInts](#bigints)
 - [NaNs](#nans)
@@ -216,7 +216,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -241,7 +241,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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+      <br  />
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@@ -257,7 +257,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -275,7 +275,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -291,7 +291,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -309,7 +309,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -325,7 +325,7 @@ Sponsorship at any level is appreciated and encouraged. If you built a paid prod
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@@ -843,6 +843,9 @@ z.string().date(); // ISO date format (YYYY-MM-DD)
 z.string().time(); // ISO time format (HH:mm:ss[.SSSSSS])
 z.string().duration(); // ISO 8601 duration
 z.string().base64();
+
+// added in Zod 3.24
+z.string().jwt();
 ```
 
 > Check out [validator.js](https://github.com/validatorjs/validator.js) for a bunch of other useful string validation functions that can be used in conjunction with [Refinements](#refine).
@@ -1006,6 +1009,20 @@ const ipv6Cidr = z.string().cidr({ version: "v6" });
 ipv6Cidr.parse("192.168.1.1"); // fail
 ```
 
+### JWTs
+
+> Added in Zod 3.24
+
+The `z.string().jwt()` method validates the string is a valid 3-part JWT. The JWT must contain type claim in the protected header.
+
+> This does not verify your JWT cryptographically! It merely ensures its in the proper format. Use a library like [jsonwebtoken](https://github.com/auth0/node-jsonwebtoken) to verify the JWT signature, parse the token, and read the claims.
+
+To constrain the JWT to a specific algorithm:
+
+```ts
+z.string().jwt({ alg: "RS256" });
+```
+
 <br/>
 
 ## Numbers