import { McpAgent } from "agents/mcp";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from "zod";
// Define our MCP agent with tools
export class MyMCP extends McpAgent {
server = new McpServer({
name: "Heygen MCP",
version: "1.0.0",
});
async init(heygenApiKey: string) {
// Simple addition tool
this.server.tool(
"add",
{ a: z.number(), b: z.number() },
async ({ a, b }: { a: number; b: number }) => ({
content: [{ type: "text", text: String(a + b) }],
})
);
// Calculator tool with multiple operations
this.server.tool(
"calculate",
{
operation: z.enum(["add", "subtract", "multiply", "divide"]),
a: z.number(),
b: z.number(),
},
async ({ operation, a, b }: { operation: string; a: number; b: number }) => {
let result: number = 0;
switch (operation) {
case "add":
result = a + b;
break;
case "subtract":
result = a - b;
break;
case "multiply":
result = a * b;
break;
case "divide":
if (b === 0)
return {
content: [
{
type: "text",
text: "Error: Cannot divide by zero",
},
],
};
result = a / b;
break;
}
return { content: [{ type: "text", text: String(result) }] };
}
);
// HeyGen video creation tool
this.server.tool(
"create_heygen_video",
{
avatar_id: z.string(),
voice_id: z.string(),
input_text: z.string(),
background: z.string().optional(), // e.g., "#008000"
},
async (
{
avatar_id,
voice_id,
input_text,
background,
}: { avatar_id: string; voice_id: string; input_text: string; background?: string }
) => {
const HEYGEN_API_KEY = heygenApiKey;
const body = {
video_inputs: [
{
character: {
type: "avatar",
avatar_id,
avatar_style: "normal",
},
voice: {
type: "text",
input_text,
voice_id,
},
background: background
? { type: "color", value: background }
: undefined,
},
],
dimension: {
width: 1280,
height: 720,
},
};
try {
const response = await fetch("https://api.heygen.com/v2/video/generate", {
method: "POST",
headers: {
"X-Api-Key": HEYGEN_API_KEY,
"Content-Type": "application/json",
},
body: JSON.stringify(body),
});
if (!response.ok) {
const errorText = await response.text();
return {
content: [
{
type: "text",
text: `HeyGen API error: ${response.status} ${errorText}`,
},
],
};
}
const data = (await response.json()) as any;
if (data.error) {
return {
content: [
{
type: "text",
text: `HeyGen API error: ${JSON.stringify(data.error)}`,
},
],
};
}
return {
content: [
{
type: "text",
text: `HeyGen video created! video_id: ${data.data.video_id}`,
},
],
};
} catch (err) {
return {
content: [
{
type: "text",
text: `Request failed: ${err}`,
},
],
};
}
}
);
}
}
export default {
async fetch(request: Request, env: Env & { HEYGEN_API_KEY: string }, ctx: ExecutionContext) {
const url = new URL(request.url);
if (url.pathname === "/sse" || url.pathname === "/sse/message") {
const mcp = new MyMCP();
await mcp.init(env.HEYGEN_API_KEY);
return mcp.server.fetch(request, env, ctx);
}
if (url.pathname === "/mcp") {
const mcp = new MyMCP();
await mcp.init(env.HEYGEN_API_KEY);
return mcp.server.fetch(request, env, ctx);
}
return new Response("Not found", { status: 404 });
},
};
