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.
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 <VERSION_ID> --debug \
--json '{"facts":{"loyaltyTier":"PLATINUM","purchaseSubtotalUsd":150}}'
# 5. Deploy
lexq deploy publish --group-id <GROUP_ID> --version-id <VERSION_ID> --memo "v1"
lexq deploy live --group-id <GROUP_ID> --version-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.
The deploy, rollback, and undeploy tools are marked as destructive, so a client
can ask you before running them.
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.
Revision
How a client reaches it
2026-07-28
A per-request _meta envelope. No handshake.
2025-11-25
The initialize handshake.
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.
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.
Variable
Overrides
LEXQ_API_KEY
apiKey
PARTNER_BASE_URL
baseUrl
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