LagsmithLagsmith documentation
Lagsmith slows down and breaks the network for one app at a time on your Mac, including apps in the iOS Simulator.
Getting started
Install Lagsmith and allow its network extension.
Presets and custom conditions
Edge to WiFi, custom bandwidth, latency, jitter and loss, profiles and host rules.
Failure modes
Airplane Mode, refused connections, time-outs, outages, failing one endpoint.
Request monitoring
Requests, search filters, HAR export and the mini monitor.
Automation
UI test helper, ivar, lagsmith:// links and the HTTP API.
MCP for AI agents
Claude Code, Cursor, Codex, Claude Desktop and Windsurf.