Build dialogue and support Agents

Build conversational, generation, routing, triage, and customer-support Agents from bounded history, turns, Tools, and escalation.

Before you begin

Define the Channel that authenticates callers, the logical Model binding, the bounded history the Agent may read, and any Resources a support action requires. Decide which answers can complete automatically and which outcomes require an escalation or approval. Conversation history is context; a committed fact is workflow truth.

Steps

1. Start with ledger → turn → commit. Give the turn one objective, bounded prior facts, and only the Tools allowed for this caller.
2. Use a structured artifact or a second turn when routing must choose a queue, specialist, or child task. Do not let raw model text select a Resource CRN.
3. Use await for a human decision and spawn for independently durable specialist work. Use neither for ordinary in-process helper functions.
4. Commit the disposition, case reference, or final response that later Runs must trust.

import { agent, type HistoryView } from "@constal/sdk";

export default agent({
  id: "support", version: "1.0.0", model: "model",
  async onMessage(message, ctx) {
    const history = await ctx.ledger.view<HistoryView>("history");
    const response = await ctx.turn({
      system: "Resolve the request. Use offered Tools for facts; escalate when authority is missing.",
      objective: message,
      context: { facts: history.facts },
      tools: ["lookup_customer", "update_ticket"],
    });

    const result = { kind: "support-response", text: response.message.content };
    await ctx.commit(result);
    return result;
  },
});

For a pure content Agent, remove Tools and history that the task does not need. For a router, constrain turn.artifact to a small validated destination set, then dispatch through registered code. For support, keep customer-specific Resources and Credentials behind customer- or principal-scoped bindings established from authenticated Channel identity.

Verify

Start a controlled conversation and inspect the Run journal. Confirm history is bounded, only declared Tools appear, every Tool call targets a pinned Resource, and the final disposition is committed once. Test an unknown caller, a denied action, an ambiguous provider outcome, and an escalation timeout. Replaying the same event must not duplicate a ticket update.

Next steps

Read Channels and Auth Providers, Resources and Tools, Scoped bindings, and Human waits and controls.