05 Tools and Context

type Variables = {
  userId: string;
};

export const app = new Hono<{ Variables: Variables }>();

app.use("/api/*", async (c, next) => {
  const userId = c.req.header("x-user-id");

  if (!userId) {
    return c.json({ error: "unauthorized" }, 401);
  }

  c.set("userId", userId);
  await next();
});

import { z } from "zod";
import { AgentBuilder, createTool } from "@anvia/core";
import { model } from "./ai/support-agent";
import { orders } from "./db/orders";

export function createSupportAgent(scope: { userId: string }) {
  const lookupOrder = createTool({
    name: "lookup_order",
    description: "Look up one order owned by the current user.",
    input: z.object({
      orderId: z.string(),
    }),
    output: z.object({
      status: z.string(),
    }),
    async execute({ orderId }) {
      return orders.findForUser(scope.userId, orderId);
    },
  });

  return new AgentBuilder("support", model)
    .instructions("Use tools for account-specific data.")
    .tool(lookupOrder)
    .defaultMaxTurns(3)
    .build();
}

import { zValidator } from "@hono/zod-validator";
import { z } from "zod";

const SupportRequest = z.object({
  message: z.string().trim().min(1, "message is required"),
});

app.post("/api/support", zValidator("json", SupportRequest), async (c) => {
  const userId = c.get("userId");
  const { message } = c.req.valid("json");

  const agent = createSupportAgent({ userId });
  const response = await agent.prompt(message).send();

  return c.json({ output: response.output });
});

const agent = new AgentBuilder("support", model)
  .instructions("Use retrieved support docs when relevant.")
  .dynamicContext(supportDocsIndex, {
    topK: 3,
    threshold: 0.7,
  })
  .tool(lookupOrder)
  .build();