measurement-uncertainty-mcp is a Model Context Protocol server for ISO/IEC 17025 accredited calibration laboratories and organizations operating under ISO 10012:2026 measurement management systems. It implements the Guide to the Expression of Uncertainty in Measurement (JCGM 100:2008, the GUM) and its Monte Carlo supplement (JCGM 101:2008) as a set of typed tools that any MCP-compatible AI assistant can call.

What you get with the free tier (50 calls/month, no credit card):

Combined standard uncertainty from a measurement model (law of propagation)
Expanded uncertainty U = k · u_c with effective degrees of freedom (Welch–Satterthwaite)
Monte Carlo propagation per JCGM 101 (configurable n, coverage interval)
Type A and Type B component evaluation
Sensitivity coefficient computation via an AST-whitelisted formula parser (no eval, no RCE)

Five queries calibration techs and metrology managers run against the server every day:

"Compute the expanded uncertainty for this voltage divider given 4 input quantities."
"Cross-check the GUM result against Monte Carlo at n=10^6."
"Walk me through which contributions dominate this budget."
"Generate a JCGM-formatted uncertainty statement for the calibration certificate."
"Sanity-check this Type B distribution choice for a digital indication."

Built and maintained by a working measurement-systems engineer. Templates for university teaching labs, semiconductor metrology, and ISO/IEC 17025 calibration are seeded; ISO 10012:2026 traceability templates ship in the Team tier.

Free tier 50 calls/month. Team tier (early access): request via the README.