Heystack — Claude Code MCP server: monitor AI apps
Track traces, logs, and LLM costs for your AI applications from your editor. Heystack connects to Claude Code, Cursor, Copilot, and other agents—letting them set up monitoring, find crash causes, and manage alerts.
claude mcp add --transport http heystack https://mcp.heystack.dev/mcpWhat Heystack does
Heystack is an observability platform for AI applications. Its MCP server brings that visibility into your coding environment: search traces and logs in plain English, open and understand individual traces, replay session histories, spot problematic releases, and set up alerts. The server includes two skills: heystack-setup detects your runtime (Next.js, Cloudflare Workers, Node, browser, Android) and wires the right data collection method; heystack-investigate walks an agent through the incident loop—overview, traces, sessions, code fix, and verification.
Authentication uses OAuth; no API keys to manage. By default, the MCP server exposes core tools and management features—app health, incident search, sampling and alert rules. Editing the plugin URL to include team or advanced unlocks team administration and SQL queries. Sensitive actions like minting tokens or sending data externally always ask for confirmation first.
What it helps with
- find what broke in production after the last deploy
- see how much you're spending on LLM calls
- understand why an endpoint is slower than before
- set up monitoring in a new AI project via your agent
- replay a user's session from logs
Example prompts for the agent
- List my Heystack apps and their health status
- Why is /checkout failing since the last deploy?
- Set up Heystack in this project and verify it's receiving data
How to install Heystack
Platform CLI: remote server
claude mcp add --transport http heystack https://mcp.heystack.dev/mcpPlatform CLI: remote server
codex mcp add heystack --url https://mcp.heystack.dev/mcpConfig file
{
"mcpServers": {
"heystack": {
"url": "https://mcp.heystack.dev/mcp"
}
}
}Config file
{
"servers": {
"heystack": {
"type": "http",
"url": "https://mcp.heystack.dev/mcp"
}
}
}Platform CLI: remote server
gemini mcp add -t http heystack https://mcp.heystack.dev/mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Heystack
How do I install Heystack in Claude Code?
Run claude mcp add --transport http heystack https://mcp.heystack.dev/mcp. Then run /mcp to sign in with OAuth and select your organization.
What does Heystack do?
It collects traces, logs, and LLM call metrics from your applications and gives your agent tools to search them in natural language, open and explain traces, view and replay sessions, spot problem releases, and configure alerts.
Which platforms support Heystack?
The MCP server works with Claude Code, Codex, Cursor, GitHub Copilot, Windsurf, Cline, Zed, and Gemini CLI. Each platform has its own setup instructions in the docs.
