Agent Browser Plugin

The Agent Browser plugin adds a browser automation skill backed by the agent-browser CLI.

Install

Install the plugin package alongside @sentry/junior:

pnpm add @sentry/junior @sentry/junior-agent-browser

Runtime setup

List the plugin in juniorNitro({ pluginPackages: [...] }):

nitro.config.ts

juniorNitro({
  pluginPackages: ["@sentry/junior-agent-browser"],
});

Configure environment variables

No environment variables are required for this plugin.

Plugin-specific setup

This plugin provisions browser automation as part of the sandbox snapshot:

• Plugin manifest: agent-browser
• Skill: /agent-browser
• Runtime dependency: agent-browser npm package installed in the snapshot
• Runtime postinstall: agent-browser install to provision browser binaries in the snapshot

Use the skill in a thread:

/agent-browser Open https://example.com, capture a screenshot, and summarize what is on the page.

Verify

1. Run /agent-browser with a simple open-and-snapshot request.
2. Confirm the turn can execute agent-browser commands successfully.
3. Confirm the output includes concrete page evidence such as the final URL or screenshot references.

Failure modes

• command not found: agent-browser: the runtime dependency install did not complete. Retry the turn and check sandbox snapshot setup logs.
• Browser launch fails during the turn: browser binaries were not provisioned successfully. Rebuild the snapshot so agent-browser install runs again.
• Stale element references like @e*: the DOM changed after the snapshot was taken. Run a fresh snapshot -i after navigation or UI updates.
• Page appears incomplete: the page had not finished loading before the next action. Wait explicitly with agent-browser wait --load networkidle before interacting.

Next step

Continue with Plugins to build provider-specific extensions or review Security Hardening for production controls.