diff --git a/.vscode/settings.json b/.vscode/settings.json
index dfa312dcd2..78a1c974a0 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -14,6 +14,7 @@
         "gptoolsjs",
         "llmrequest",
         "localai",
+        "mardownify",
         "millis",
         "ollama",
         "openai",
diff --git a/docs/genaisrc/genaiscript.d.ts b/docs/genaisrc/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/docs/genaisrc/genaiscript.d.ts
+++ b/docs/genaisrc/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/docs/src/content/docs/reference/scripts/parsers.md b/docs/src/content/docs/reference/scripts/parsers.md
index d3999ea3bb..a878fd8f1d 100644
--- a/docs/src/content/docs/reference/scripts/parsers.md
+++ b/docs/src/content/docs/reference/scripts/parsers.md
@@ -227,3 +227,19 @@ for the current model. This is useful for estimating the number of prompts that
 ```js
 const count = parsers.tokens("...")
 ```
+
+## math
+
+The `parsers.math` function uses [mathjs](https://mathjs.org/) to parse a math expression.
+
+```js
+const res = parsers.math("1 + 1")
+```
+
+## validateJSON
+
+The `parsers.validateJSON` function validates a JSON string against a schema.
+
+```js
+const validation = parsers.validateJSON(schema, json)
+```
diff --git a/docs/src/content/docs/reference/scripts/schemas.mdx b/docs/src/content/docs/reference/scripts/schemas.mdx
index 7f188574e6..ce985f3b14 100644
--- a/docs/src/content/docs/reference/scripts/schemas.mdx
+++ b/docs/src/content/docs/reference/scripts/schemas.mdx
@@ -144,3 +144,11 @@ and can confuse the LLM.
 
 GenAIScript will automatically try to repair the data by issues additional messages 
 back to the LLM with the parsing output.
+
+## Runtime Validation
+
+Use `parsers.validateJSON` to validate JSON when running the script.
+
+```js
+const validation = parsers.validateJSON(schema, json)
+```
\ No newline at end of file
diff --git a/genaisrc/genaiscript.d.ts b/genaisrc/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/genaisrc/genaiscript.d.ts
+++ b/genaisrc/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/core/src/genaisrc/genaiscript.d.ts b/packages/core/src/genaisrc/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/core/src/genaisrc/genaiscript.d.ts
+++ b/packages/core/src/genaisrc/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/core/src/parsers.test.ts b/packages/core/src/parsers.test.ts
new file mode 100644
index 0000000000..b54fe557c8
--- /dev/null
+++ b/packages/core/src/parsers.test.ts
@@ -0,0 +1,60 @@
+import { describe, beforeEach, test } from "node:test"
+import assert from "node:assert/strict"
+import { createParsers } from "./parsers"
+import { MarkdownTrace } from "./trace"
+
+describe("parsers", () => {
+    let trace: MarkdownTrace
+    let model: string
+    let parsers: ReturnType<typeof createParsers>
+
+    beforeEach(() => {
+        trace = new MarkdownTrace()
+        model = "test model"
+        parsers = createParsers({ trace, model })
+    })
+
+    test("JSON5", () => {
+        const result = parsers.JSON5('{"key": "value"}')
+        assert.deepStrictEqual(result, { key: "value" })
+    })
+
+    test("YAML", () => {
+        const result = parsers.YAML("key: value")
+        assert.deepStrictEqual(result, { key: "value" })
+    })
+
+    test("XML parser", () => {
+        const result = parsers.XML("<key>value</key>")
+        assert.deepStrictEqual(result, { key: "value" })
+    })
+
+    test("TOML", () => {
+        const result = parsers.TOML('key = "value"')
+        assert.equal(result.key, "value")
+    })
+
+    test("frontmatter", () => {
+        const result = parsers.frontmatter("---\nkey: value\n---\n")
+        assert.deepStrictEqual(result, { key: "value" })
+    })
+
+    test("math", () => {
+        const res = parsers.math("1 + 3")
+        assert.strictEqual(res, 4)
+    })
+
+    test("validateJSON", () => {
+        const res = parsers.validateJSON(
+            {
+                type: "object",
+                properties: {
+                    key: { type: "string" },
+                },
+                required: ["key"],
+            },
+            { key: "value" }
+        )
+        assert.strictEqual(res.valid, true)
+    })
+})
diff --git a/packages/core/src/parsers.ts b/packages/core/src/parsers.ts
index f77712dcf5..d3d3210af7 100644
--- a/packages/core/src/parsers.ts
+++ b/packages/core/src/parsers.ts
@@ -16,6 +16,7 @@ import { treeSitterQuery } from "./treesitter"
 import { parsePdf } from "./pdf"
 import { HTMLToText } from "./html"
 import { MathTryEvaluate } from "./math"
+import { validateJSONWithSchema } from "./schema"
 
 export function createParsers(options: {
     trace: MarkdownTrace
@@ -82,5 +83,7 @@ export function createParsers(options: {
         code: async (file, query) =>
             await treeSitterQuery(file, query, { trace }),
         math: (expression) => MathTryEvaluate(expression, { trace }),
+        validateJSON: (schema, content) =>
+            validateJSONWithSchema(content, schema, { trace }),
     })
 }
diff --git a/packages/core/src/toml.ts b/packages/core/src/toml.ts
index 47ca9e3de9..30884a10d5 100644
--- a/packages/core/src/toml.ts
+++ b/packages/core/src/toml.ts
@@ -2,7 +2,8 @@ import { parse } from "toml"
 
 export function TOMLTryParse(text: string, options?: { defaultValue?: any }) {
     try {
-        return parse(text)
+        const res = parse(text)
+        return res
     } catch (e) {
         return options?.defaultValue
     }
diff --git a/packages/core/src/types/prompt_template.d.ts b/packages/core/src/types/prompt_template.d.ts
index fb19f01a50..54bfb2310b 100644
--- a/packages/core/src/types/prompt_template.d.ts
+++ b/packages/core/src/types/prompt_template.d.ts
@@ -857,6 +857,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/genaisrc/genaiscript.d.ts b/packages/sample/genaisrc/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/genaisrc/genaiscript.d.ts
+++ b/packages/sample/genaisrc/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/genaisrc/node/genaiscript.d.ts b/packages/sample/genaisrc/node/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/genaisrc/node/genaiscript.d.ts
+++ b/packages/sample/genaisrc/node/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/genaisrc/python/genaiscript.d.ts b/packages/sample/genaisrc/python/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/genaisrc/python/genaiscript.d.ts
+++ b/packages/sample/genaisrc/python/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/genaisrc/style/genaiscript.d.ts b/packages/sample/genaisrc/style/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/genaisrc/style/genaiscript.d.ts
+++ b/packages/sample/genaisrc/style/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/src/aici/genaiscript.d.ts b/packages/sample/src/aici/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/src/aici/genaiscript.d.ts
+++ b/packages/sample/src/aici/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/src/errors/genaiscript.d.ts b/packages/sample/src/errors/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/src/errors/genaiscript.d.ts
+++ b/packages/sample/src/errors/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/src/makecode/genaiscript.d.ts b/packages/sample/src/makecode/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/src/makecode/genaiscript.d.ts
+++ b/packages/sample/src/makecode/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/src/tla/genaiscript.d.ts b/packages/sample/src/tla/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/src/tla/genaiscript.d.ts
+++ b/packages/sample/src/tla/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/packages/sample/src/vision/genaiscript.d.ts b/packages/sample/src/vision/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/packages/sample/src/vision/genaiscript.d.ts
+++ b/packages/sample/src/vision/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {
diff --git a/slides/genaisrc/genaiscript.d.ts b/slides/genaisrc/genaiscript.d.ts
index 6f855d1cdc..a64d52cbb4 100644
--- a/slides/genaisrc/genaiscript.d.ts
+++ b/slides/genaisrc/genaiscript.d.ts
@@ -892,6 +892,13 @@ interface Parsers {
      * @param expression math expression compatible with mathjs
      */
     math(expression: string): string | number | undefined
+
+    /**
+     * Using the JSON schema, validates the content
+     * @param schema JSON schema instance
+     * @param content object to validate
+     */
+    validateJSON(schema: JSONSchema, content: any): JSONSchemaValidation
 }
 
 interface AICIGenOptions {