Stop your agent from acting on overconfident guesses.

SimEngine gives an AI agent a real outcome-distribution calculator: schema-contracted Monte Carlo simulation, chance/CVaR safety constraints, and a proceed / escalate decision gate — over MCP, pure Python stdlib, zero dependencies.

Run it now

uvx simengine-mcp

Or find it on the official MCP registry, or clone the engine — web UI, HTTP API, and CLI included. Python 3.8+ is the only requirement.

Why trust the numbers

The forecast pipeline is backtested on 2,819 walk-forward monthly forecasts over up to seven decades of public FRED data — every one produced through the real engine path and scored with proper scoring rules (Brier, log loss) plus calibration error (ECE) (full report):

TasknBrierECE
CPI inflation > 0.25% MoM8310.23170.081
Industrial production falls1,1680.23790.060
Unemployment rate rises8200.25150.171

This validates that engine-produced probabilities are calibrated, not that they beat markets. SimEngine models outcome risk — the spread of results given uncertain inputs — as decision support. It is not financial advice and issues no trade signals.

The decision gate

An agent hands decide_under_uncertainty a quick model of a decision and the outcome range it can live with. The engine runs thousands of futures and answers: “82% of simulated outcomes keep cash above zero — that clears your 80% bar, proceed” — or escalate, with the tail risk spelled out. Nine tools total: simulate, validate, optimize, Bayesian update, sensitivity, convergence, baseline comparison, domain listing, and the gate.

Hosted endpoint — join the waitlist

A managed, agent-ready HTTPS endpoint is coming: no install, instant API key, free tier. Leave an email and you'll get an invite when it opens.

Join the waitlist by email

One email when the hosted tier opens. Nothing else.