Building Observability for MCP Servers: FleetWatch + MCP Blackbox Suggested

As more of my tooling starts talking to MCP servers instead of calling APIs directly, I kept running into the same gap: there's no lightweight way to know when an MCP server goes down, and no way to see what actually happened when something breaks mid-run. So I built two small, focused tools to close that gap - FleetWatch and MCP Blackbox.

The problem

MCP servers are quickly becoming the standard way AI agents reach tools, but the ecosystem is still missing basic infrastructure plumbing: uptime monitoring, latency tracking, and forensic debugging. When an agent run fails, "the MCP server did something weird" is usually where the trail goes cold.

I wanted both tools to stay narrow and not overlap with things I'd already built (mcp-schema-watch for schema drift, skillcheck for SKILL.md linting, Swarm Trace Viewer for swarm-run analysis). So FleetWatch and MCP Blackbox split the job in half - one watches, one records.

🩺 FleetWatch - uptime & health monitoring

FleetWatch pings your registered MCP servers on a schedule and tracks:

• Uptime - is the server actually reachable
• Latency - how long it's taking to respond
• Response correctness - not just "did it respond" but "did it respond the way it should"

The moment a server goes down, degrades, or recovers, FleetWatch fires an alert. It's built with TypeScript, NestJS, and Next.js, communicates over WebSockets for live status updates, and ships with a full test suite plus a GitHub Actions CI workflow.

🔗 https://github.com/DIYA73/fleetwatch

🕵️ MCP Blackbox - the forensic layer

FleetWatch tells you something broke. MCP Blackbox tells you why. It's a recording proxy that sits in front of your MCP traffic and captures full request/response payloads.

The interesting design decision was around retention: instead of keeping everything (expensive) or nothing (useless when you actually need it), Blackbox permanently pins anything around a failure and prunes the rest. A flight recorder for your MCP servers - the data you need, right when you need it, without the storage bill of logging forever.

Same stack as FleetWatch - TypeScript, NestJS, Next.js, WebSockets - so the two integrate cleanly.

🔗 https://github.com/DIYA73/mcp-blackbox

Built to work together

FleetWatch and MCP Blackbox are deliberately separate - you can run either one on its own. But paired together, the workflow is simple: FleetWatch catches the failure in real time, and Blackbox already has the trace waiting for you.

Both are open source and public on GitHub - issues, stars, and PRs are always welcome. If you're building on MCP and hitting the same "I have no idea what just happened" wall, I'd love to hear how you're solving it.