fix: do not serialize input schema in tool definitions (#617)

This change updates the manifest method of the Gram Functions TS
framework to avoid JSON-serializing the input schema for tool
definitions. This was a mistake since the server is expecting a literal
object for the schema.

Author: disintegrator

.changeset/neat-jars-film.md

@@ -0,0 +1,7 @@
+---
+"@gram-ai/functions": patch
+---
+
+Updated the `manifest()` method of the Gram Functions TS framework to avoid
+JSON-serializing the input schema for tool definitions. This was a mistake since
+the server is expecting a literal object for the schema.

ts-framework/functions/src/framework.test.ts

@@ -284,17 +284,28 @@ test("generates a manifest", () => {
     tools: [
       {
         name: "echo",
-        inputSchema: expect.stringContaining("message"),
+        inputSchema: expect.objectContaining({
+          type: "object",
+          properties: { message: { type: "string" } },
+          required: ["message"],
+        }),
       },
       {
         name: "add",
         description: "Add two numbers",
-        inputSchema: expect.stringContaining(`"required":["a","b"]`),
+        inputSchema: expect.objectContaining({
+          type: "object",
+          properties: { a: { type: "number" }, b: { type: "number" } },
+          required: ["a", "b"],
+        }),
       },
       {
         name: "shout",
         description: "Shouts the input",
-        inputSchema: expect.any(String),
+        inputSchema: expect.objectContaining({
+          type: "object",
+          properties: {},
+        }),
         variables: {
           MESSAGE: { description: "The message to shout" },
         },

ts-framework/functions/src/framework.ts

@@ -49,7 +49,7 @@ export type Manifest = {
   tools: Array<{
     name: string;
     description?: string;
-    inputSchema: string;
+    inputSchema: unknown;
     variables?: Record<string, VarDef>;
   }>;
 };
@@ -223,11 +223,11 @@ export class Gram<
       const result: {
         name: string;
         description?: string;
-        inputSchema: string;
+        inputSchema: unknown;
         variables?: Record<string, VarDef>;
       } = {
         name: tool.name,
-        inputSchema: JSON.stringify(inputSchema),
+        inputSchema: inputSchema,
       };
       if (tool.description != null) {
         result.description = tool.description;