> ## Documentation Index
> Fetch the complete documentation index at: https://docs.major.build/llms.txt
> Use this file to discover all available pages before exploring further.

# App Triggers

> Let your deployed apps start and manage agent runs.

Your deployed Major apps can trigger agents at runtime and interact with their runs. A common pattern is a dashboard that, on load, kicks off several agents — summarize my inbox, prep my calendar, review open PRs — and renders their results as they come in.

## Attaching an agent to an app

An app can only trigger agents that have been explicitly attached to it. Attaching requires edit access to both the app and the agent — it's a deliberate action, not inferred from your code. Once attached, the app can start and manage runs of that agent.

## Triggering from code

Use the `@major-tech/agents-client/next` package. The client reads your app's Major credentials from the environment, so there's nothing to wire up manually.

```typescript theme={null}
import { createAgentsClient } from "@major-tech/agents-client/next";

const agents = createAgentsClient();

// Start a run — returns immediately with a run handle
const { chatThreadId } = await agents.run({
  agentId: process.env.SUMMARY_AGENT_ID!,
  prompt: "Summarize today's unread email.",
  name: "inbox-summary",
});

// Poll for progress — the last N messages of the run
const messages = await agents.getAgentContent(chatThreadId, 10);
```

Runs are asynchronous: `run()` returns right away and you poll `getAgentContent` for progress. Other methods let you manage a run in flight:

| Method                                 | Description                                   |
| -------------------------------------- | --------------------------------------------- |
| `run({ agentId, prompt, name? })`      | Start a run; returns a `chatThreadId` handle. |
| `sendMessage(chatThreadId, message)`   | Send a follow-up message to a live run.       |
| `stopAgent(chatThreadId)`              | Stop a run (no-op if it already finished).    |
| `getRunningInstancesOfAgent(agentId?)` | List currently live runs.                     |
| `getAgentContent(chatThreadId, n?)`    | Read the last `n` messages of a run.          |

## Limits

To prevent runaway costs, an app may have a limited number of live agent runs at once; further `run()` calls are rejected until some finish. An app can only manage the runs it started. Manual and scheduled runs aren't subject to this per-app cap.

<Note>
  `sendMessage` to a finished run throws `AgentRunNotActiveError` — start a fresh run instead. Calls also fail if the agent isn't attached to the app or the caller lacks access.
</Note>