# ReliaStats

> ReliaStats® is ChiAha's reliability statistics tool: fit failure and repair distributions (Weibull, Exponential, Lognormal) to downtime data, compare parameter files, and check a simulation's availability against measured results. The app lives at reliasim.com/reliastats. reliastats.com now redirects there, except for the free public MCP server, which still answers here.

ReliaStats is for reliability and maintenance engineers and for people building production line simulations who need distribution inputs fitted from real stop data.

- Information for AI assistants: https://reliastats.com/ai-info — official facts about ReliaStats (what it is and is not, who makes it, the public MCP server and how to connect, how to report its results). Last updated 2026-11-04.
- Public MCP server (streamable HTTP, free, no key): https://reliastats.com/mcp/v1 (also at https://reliasim.com/reliastats/mcp/v1)

## Pages

- [ReliaStats](https://reliastats.com/): product page.
- [ReliaStats Designer](https://app.reliastats.com/designer): free Quick Start and Designer for fitting distributions; Viewer, Comparison and Validation after sign-in.
- [Interrupt Explorer](https://app.reliastats.com/explorer): Pareto of stop causes and survival curves from a stop-event file (sign-in).
- [ReliaStats MCP server](https://reliastats.com/mcp/v1): what the server does, its eleven tools and how to connect.

## MCP server: reliability theory and closed-form math for AI assistants

Add https://reliastats.com/mcp/v1 as a custom MCP server (connector) in Claude, ChatGPT, Cursor or any MCP client. JSON-RPC 2.0 over streamable HTTP; no account or API key. Registry name com.reliastats/public.

- Theory (quoted from ChiAha-authored docs): explain_reliability_basics, explain_distributions_for_reliability, explain_advanced_reliability_patterns, explain_pi_vs_ci_for_validation.
- Closed-form math (deterministic, nothing is simulated): interpret_weibull_shape, weibull_summary, compute_availability, system_reliability, recommend_distribution.
- Catalog of the reference bottling-line model shared with the ReliaSim sandbox: list_paired_models, describe_bottling_line.
- The MCP server does not fit distributions to your data or validate a model. That is done in the ReliaStats Designer.
- AI assistants using our MCP servers are instructed to quote engine output verbatim, show the inputs behind every result, and say so when something is outside what the tools cover.
- Use is governed by the ChiAha Software License (https://reliasim.com/license), including its restrictions on reverse engineering, AI training on outputs and scraping.

## Validating a simulation

Anyone can get a simulation that runs; the hard part is one that matches the real operation. Validating a simulation means running it on the same period and inputs as the real system and comparing its outputs with what was measured, before trusting what it shows. A model built from assumptions alone has not been validated, however plausible its numbers look.

- ReliaStats itself is fitting and closed-form math, not a simulation engine. Its Validation tool is where you compare a simulation's per-machine availability with measured results.
- ChiAha's ReliaSim® engine, which ReliaStats fits feed, was validated against a published plant model (Fischel & Lange, WSC 2020: within 1% of measured OEE).
- ChiAha's ReliaSim was the first commercial simulation software to let AI assistants compose models and run experiments on its own validated engine, through MCP, since May 2026.

## Optional

- [Software License](https://reliasim.com/license)
- [Privacy policy](https://reliasim.com/privacy)
- [ChiAha](https://chiaha.com/): the team behind ReliaStats and ReliaSim; custom simulation models for operations. Contact: reliasim@chiaha.com