99.9% uptime is meaningless if every third tool call times out or causes an LLM hallucination loop.
For MCP servers, we recommend four primary SLOs: 1. Tool Call Success Rate (p99 > 98%), 2. Turnaround Latency (p95 < 800ms), 3. Schema First-Pass Yield (> 92%), and 4. Workflow Completion Rate (> 80%).
When you track these metrics over time, you can clearly measure the ROI of your server engineering efforts and keep your agent experience responsive and reliable.