Developers

Call the verdict from anywhere

ArbiterQA is headless and agent-native. Get a key with the @rbtrqa/cli CLI, then run jobs from the API or an MCP client — name checks and sets by the same ids you see in the catalog and get a structured pass, fail, or error back.

Key and jobs

npx @rbtrqa/cli

The CLI handles your key: sign in once and it saves the key to ./.env. Run checks and sets with the jobs API. In CI, read the verdict from the job response. Published on npm.

install

# Commands: install, update, login, status, print-key, logout
npx @rbtrqa/cli --help

authenticate

# Get a key once (browser sign-in, key saved to ./.env)
npx @rbtrqa/cli login

run a job

# Run a Validation Set against a page
curl -X POST https://api.arbiterqa.com/api/jobs \
  -H "Authorization: Bearer $ARBITER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"type":"url","url":"https://example.com","validationSetId":"brand-compliance"}'

# Run a single check
curl -X POST https://api.arbiterqa.com/api/jobs \
  -H "Authorization: Bearer $ARBITER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"type":"url","url":"https://example.com","validations":["font-size-body-min-max"]}'

MCP

Model Context Protocol

Point any MCP client at the hosted endpoint to give an agent the catalog and the ability to run checks. The endpoint lives on the API host: https://api.arbiterqa.com/mcp

mcp.json

{
  "mcpServers": {
    "arbiterqa": {
      "url": "https://api.arbiterqa.com/mcp"
    }
  }
}

Catalog API

Public read endpoints

The catalog, per-check detail, and sets are public and require no auth — the same JSON that powers this site and the MCP get_validation tool. Running a job (which spends credits) happens on the app behind your API key.

curl

# Public, no-auth catalog reads
curl https://api.arbiterqa.com/api/validations
curl https://api.arbiterqa.com/api/validations/alt-text-on-images
curl https://api.arbiterqa.com/api/validation-sets
curl https://api.arbiterqa.com/api/validation-sets/accessibility-compliance

For agents

Front-door files

Agents can read our capabilities directly. These stay on the API host where agents expect them.

llms.txtCompact capability index llms-full.txtFull contract and prose MCP endpointHosted tool server npm: @rbtrqa/cliKey management CLI

Get an API key

Create a free account with 1,000 credits, generate a key, and run your first check in minutes.

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