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LexQ is the Decision Operations Platform for engineering teams. You define business rules (conditions and actions) in a visual console, prove every change with simulation, and deploy to production — all without touching application code.
LexQ offers 4 plans: Free (1,000 executions/month), Growth (USD 99/month, 100,000 executions), Pro (USD 299/month, 1,000,000 executions), and Enterprise (custom volume and compliance). All plans include versioning, simulation, and deployment, with no per-tier rule quota. Overages on Growth and Pro are billed per execution. Pricing is locked for 10 years — limits expand over time, prices stay the same.
A Dry Run tests one input at a time — like a unit test. An Impact Simulation runs a version against hundreds or thousands of historical inputs and compares results with a baseline — like an integration test suite. Use Dry Runs during development; use Impact Simulation before deployment.
No. Once a version is published (DRAFT to ACTIVE), it is permanently locked. To make changes, clone the published version to create a new DRAFT, modify the rules, then publish and deploy the new version.
Production execution of that group is rejected with 403 (P-009), and a composite request that includes it is rejected as a whole. The deployed version and any A/B test are kept, and Dry Run, Impact Simulation, and Decision Replay keep working, so you can verify a fix before you re-enable the group. See Disabling a Group.
The Console and documentation support English and Korean. The API and CLI work with any language for fact values and rule names — they are treated as opaque strings.
Call the Execution API with your input facts, and the engine evaluates your rules. In the response, mutatedFacts lists the facts your rules changed. When MUTATE_FACT changes a number, generatedVariables also gives the amount it changed by, as a positive or negative number. A BLOCK action sets isBlocked and blockReason and lets the call finish, so your service decides whether to refuse the request. decisionTraces shows which rule was selected and why the others were not. See Policy Execution for the full response and the four execution modes.
SET_FACT is an action type that assigns a literal value to a fact. It does not evaluate expressions, so it cannot do arithmetic or refer to other facts. Use it to set a flag or a label. If your request sent that fact, the new value comes back in mutatedFacts; if not, it comes back in generatedVariables. Either way, no change amount is reported.
The Model Context Protocol (MCP) is an open standard for connecting AI agents to external tools. LexQ CLI includes a built-in MCP server that exposes the full Partner API. This lets AI agents like Claude, Gemini, and Copilot manage your policies directly through natural language. See the MCP Server Guide for setup instructions.