aayushmdesai/mcp-dotnet-diagnostics

Give your AI assistant real-time visibility into your .NET application's runtime health.
Connect this Model Context Protocol server to Claude Desktop
and ask plain questions about any running .NET process — memory leaks, GC pressure, thread
starvation, allocation hotspots. Claude calls the right tools, reads real runtime data, and
tells you what's actually wrong.
---
What this looks like in practice
You ask:
> *"Why does my API have high memory usage? PID is 12345."*
Claude calls get_process_info to confirm connectivity, then get_memory_stats, then
get_gc_events — and responds:
> *"Every GC event in the last 5 seconds was a Gen2 collection triggered by AllocLarge.
> Something is continuously allocating objects above the 85KB LOH threshold at ~10.5 MB/s.
> LOH is never compacted by default — fragmentation is at 55% and growing. The fix is
> ArrayPool .Shared. Rent a buffer, use it, return it."*
You don't tell Claude which tools to call. It figures that out from your question.
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Tools
| Tool | What it returns | Reach for it when... |
|------|----------------|----------------------|
| get_process_info | Name, PID, uptime, .NET version, OS | Starting any investigation — confirms the process is reachable |
| get_memory_stats | GC heap, LOH size, alloc rate, Gen0/1/2 counts, fragmentation | Memory is high or growing |
| get_gc_events | Per-collection timeline — generation, reason, timestamp | GC pauses are affecting latency |
| get_thread_stats | ThreadPool count, queue depth, completed items, lock contention | Requests are slow or backing up |
| get_event_counters | All 27 System.Runtime metrics in one snapshot | You want a broad health overview |
| get_environment_info | Runtime config, filtered env vars (no secrets) | Debugging configuration issues |
| list_counters | Raw EventCounter names and current values | Discovering what's available on an unfamiliar process |
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Installation
**1. Install the tool**
Requires .NET 8 SDK or later. Get it here if needed.
**2. Add to Claude Desktop**
Open ~/Library/Application Support/Claude/claude_desktop_config.json while Claude Desktop
is **fully quit** (Cmd+Q — not just the window closed), then add:
**3. Reopen Claude Desktop**
The dotnet-diagnostics connector appears in the tools menu. Ask it about any .NET process.
---
> **macOS: the TMPDIR step is not optional.**
>
> The .NET diagnostics protocol finds processes through a Unix socket. On macOS, that socket
> lives under $TMPDIR — not /tmp/ where the library looks by default. Without this,
> every tool call returns "process not found."
>
> Find yours with: echo $TMPDIR
---
> **Want to contribute or build from source?**
> See CONTRIBUTING.md for how to clone, build, and add new tools.
Usage
Find the PID of your target process:
Then ask Claude naturally:
"Do a full health check on PID 12345."
"Why is memory climbing on PID 12345?"
"Any thread starvation in PID 12345?"
"What's the GC situation on PID 12345?"