@temporalio/agent-harness-svelte

A Svelte 5 binding for @temporalio/agent-harness-client: AgentSession, a reactive handle on one harness agent session.

<script lang="ts">
  import { AgentSession } from "@temporalio/agent-harness-svelte";
  import type { TicTacToeAgent } from "./client_sdk/TicTacToeAgent"; // from harness-codegen

  let { sessionId } = $props();
  const agent = new AgentSession<TicTacToeAgent>({ get sessionId() { return sessionId; } });
  const board = $derived(agent.states.board);
</script>

{#if board}
  {#each board.cells as cell, i (i)}
    <button onclick={() => agent.sendMessage("play", { cell: i + 1 })}>{cell ?? ""}</button>
  {/each}
{/if}

• Reading opens the connection. The first effect or markup to read any field opens the session's stream; it closes once nothing reads it, so unmounting the last view releases it.
• Getter options follow changes. A get sessionId() switches the session when its value does.
• One connection per session. Call createHarnessContext() in a parent component and every AgentSession below it with the same session id shares one connection and one state.
• The whole tree. messages, states and agentStatus are the root agent's; agents and agent(id) reach every subagent, and a subagent part's messageId names the child message it ran. pendingApprovals and pendingCallbacks collect waiting tool calls from all of them.

Development

This package links ../client and resolves it through that package's build:

(cd ../client && npm ci && npm run build)
npm ci
npm run check && npm test && npm run build