LexQ

LexQ CLI

The Decision Operations Platform for engineering teams.

CLI and MCP server for LexQ. Move business rules out of

your deploy pipeline, prove every change with Impact Simulation, and ship without

a git push.

[Website](https://lexq.io) · [Docs](https://docs.lexq.io) · [Console](https://console.lexq.io) · [MCP Registry](https://registry.modelcontextprotocol.io)

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Why LexQ?

Your business rules, such as pricing, promotions, fee logic, and eligibility checks, change often. But every change ships through the same PR → review → staging → deploy cycle as your core application code, so even a small change waits for the next release.

LexQ keeps those rules out of your code. Your service calls the LexQ API to evaluate them. You change rules in a visual console or through this CLI, test each change with Impact Simulation against past executions or a dataset you upload, and deploy them without an application release.

Every decision leaves a full audit trail.

Install

npm install -g @lexq/cli

Or run without installing:

npx @lexq/cli

Requires Node.js 22+.

Quick Start

# 1. Authenticate

lexq auth login

Enter your API key (create one with the Manage scope at console.lexq.io → Management → API Keys)

2. Verify

lexq auth whoami

3. Start from a domain template — provisions facts, sample rules, and a policy group

lexq domain-templates list lexq domain-templates apply --template ECOMMERCE

Returns: policyGroupId, policyVersionId, factsCreated, rulesCreated

4. Test a rule against your data before shipping

lexq analytics dry-run --version-id --debug \ --json '{"facts":{"loyaltyTier":"PLATINUM","purchaseSubtotalUsd":150}}'

5. Deploy

lexq deploy publish --group-id --version-id --memo "v1" lexq deploy live --group-id --version-id --memo "Initial deploy"

For AI Agents

Claude, Cursor, and other MCP-compatible agents can use the Model Context Protocol to manage policy groups, versions, rules, and facts, run simulations and replays, deploy versions, and read execution history.

Approval happens in your MCP client, which decides which tool calls you confirm. A tool is marked as destructive when it deletes, overwrites, or cancels something, changes live traffic, cannot be undone, or counts toward your plan's usage, so a client can ask you before running it.

Claude.ai (cloud, no install)

1. Customize → Connectors → + Add → Add custom connector
2. Name it, enter https://mcp.lexq.io, and choose Sign in now
3. On the LexQ page that opens, sign in and generate a new API key for MCP, or choose I already have an API key and paste an existing one
4. The tools are now available in every conversation

Remote (Streamable HTTP)

For any MCP client that supports remote servers:

{

"mcpServers": { "lexq": { "url": "https://mcp.lexq.io" } } }

OAuth 2.1 authentication is handled automatically by your client.

Local (stdio)

Run LexQ CLI as a local MCP server:

lexq serve --mcp

Claude Desktop

Add to claude_desktop_config.json:

{

"mcpServers": { "lexq": { "command": "npx", "args": [ "-y", "@lexq/cli", "serve", "--mcp" ] } } }

VS Code / Cursor

.vscode/mcp.json:

{

"servers": { "lexq": { "command": "npx", "args": [ "-y", "@lexq/cli", "serve", "--mcp" ] } } }

Prerequisite: lexq auth login must have been run once to store an

API key in ~/.lexq/config.json, or LEXQ_API_KEY must be set in the client's

environment block.

Registry

The server is listed on the official MCP Registry as `io.lexq/lexq`. Clients that browse the registry find both the npm package and the hosted endpoint in that one entry.

Protocol Support

The local stdio server and the hosted Streamable HTTP endpoint both serve two MCP revisions from one set of tool definitions, so a client sees the same tools either way.

There is nothing to configure. The server answers in whichever revision the opening message used, so a client can move to 2026-07-28 on its own schedule and one that has not moved keeps working.

AI Agent Skills

LexQ CLI ships with AI Agent Skills: structured documentation that tells agents *how* to use each tool.

skills/

├── lexq-shared/SKILL.md Core concepts, auth, workflow ├── lexq-groups/SKILL.md Policy groups, conflict resolution, A/B testing ├── lexq-rules/SKILL.md Condition syntax, action types, mutex ├── lexq-simulation/SKILL.md Dry run, Impact Simulation, compare ├── lexq-execution/SKILL.md History, stats, failure logs, provenance, replay, latency profile └── lexq-recipes/SKILL.md End-to-end recipes

.claude/CLAUDE.md Claude Code project context AGENTS.md Universal agent guide (Cursor, Windsurf, Gemini CLI, Cline) CONTEXT.md Platform architecture & glossary

After installing @lexq/cli, agents can read skills from:

node_modules/@lexq/cli/skills/

node_modules/@lexq/cli/AGENTS.md node_modules/@lexq/cli/CONTEXT.md

Commands

lexq auth                  login | logout | whoami

lexq status API health check lexq serve Run as MCP stdio server (--mcp) lexq groups list | get | create | update | delete | reorder lexq groups ab-test start | stop | adjust lexq versions list | get | create | update | delete | clone lexq rules list | get | create | update | delete | reorder | toggle lexq facts list | create | update | delete | action-metadata | unregistered lexq domain-templates list | preview | apply lexq deploy publish | live | rollback | undeploy | history | detail | overview | deployable | diff | schedule | unschedule | schedules lexq analytics dry-run | dry-run-compare | requirements lexq analytics simulation start | status | list | cancel | export lexq analytics dataset upload | template lexq profile — per-rule latency profile lexq history list | get | stats lexq replay decision | start | list | get | cancel lexq logs list | get lexq provenance get | reveal-audits lexq webhook-subscriptions list | get | save | delete | test

Global Options

--format only changes how results are printed. A command that writes a file, such as lexq facts export, chooses the file's format with --as csv or --as json.

Configuration

Config is stored at ~/.lexq/config.json:

{

"apiKey": "YOUR_API_KEY", "baseUrl": "https://api.lexq.io/api/v1/partners", "format": "json" }

The file holds an API key in plain text. It is saved with mode 0600 inside a 0700 directory, so only its owner can read it. If an older version created it with looser permissions, the CLI tightens them the next time it saves the file.

Environment variables

These are read by the MCP server (lexq serve --mcp) and take precedence over the stored config. They let an editor or CI target an environment through the client's own config block, without writing to ~/.lexq/config.json. CLI commands use --api-key and --base-url instead.

Development

git clone https://github.com/lexq-io/lexq-cli.git

cd lexq-cli pnpm install pnpm build pnpm start -- groups list

pnpm typecheck                  # Type check

pnpm lint # ESLint pnpm build # Bundle to dist/

Checks that guard a stated fact against the thing that owns it. All of them run in CI.

pnpm enums:check                # Generated enums match the engine contract

pnpm prose:check # Numbers and code tables in prose match the contract pnpm ab-key:check # Tool descriptions still name the A/B traffic key pnpm surface:check # Nothing internal reached a public file pnpm registry:check # server.json agrees with package.json and src/mcp/server-info.json pnpm schemas:check # tools/list matches the recorded snapshot (needs a build) pnpm test:fact-key # Fact key grammar pnpm test:decimals # Metric precision display pnpm test:export-format # Export byte fidelity pnpm protocol:check # README matches the revisions the server serves

Security

Report a vulnerability through GitHub's private reporting form. The policy, including what is in scope, is in SECURITY.md.

License

Apache-2.0