Heimdall MCP: Add OpenTelemetry tracing to any MCP server without touching its code

If you've been building with MCP servers lately, you've probably hit this wall: something goes wrong (or just feels slow) and you have zero visibility into what actually happened. Which tool did Claude call? What input did it send? Did the server error silently? How long did it take? That's the gap Heimdall fills. What is Heimdall? Heimdall is a transparent proxy for MCP servers. It sits between your MCP client (Claude Desktop, OpenCode, Cursor, or any other) and your MCP server — local or remot