Slate API

The Slate API gives brokers programmatic access to every platform feature — orders, accounts, instruments, transactions, real-time market data, and complete broker back-office operations.

Base URL

https://api.{your-broker-domain}

Every broker runs on their own subdomain. Replace {your-broker-domain} with the domain issued during onboarding.

Authentication

All authenticated requests require a Bearer token in the Authorization header:

Authorization: Bearer <access_token>

Tokens are obtained via the login endpoints documented under Authentication.

Rate Limits

Bucket	Limit
Authenticated endpoints	300 requests / minute / user
Registration endpoint	600 requests / minute / IP

Responses include standard X-RateLimit-* headers when a limit applies.

Errors

The API uses conventional HTTP status codes. Error responses are JSON:

{
  "detail": "Human-readable message",
  "error": "machine_readable_code"
}

Code	Meaning
`400`	Validation failed — see `detail`
`401`	Missing or invalid credentials
`403`	Credentials valid but insufficient scope
`404`	Resource not found
`409`	Conflict — typically a duplicate or state mismatch
`429`	Rate limit exceeded
`5xx`	Platform error — safe to retry with exponential backoff

Versioning

The API is versioned through its hostname. Breaking changes ship on a new subdomain; non-breaking additions roll out in place and are announced in the changelog.

Authentication — obtain and refresh access tokens
API Reference — the full endpoint catalog

Introduction

Base URL

Authentication

Rate Limits

Errors

Versioning

Next

​Base URL

​Authentication

​Rate Limits

​Errors

​Versioning

​Next

Base URL

Authentication

Rate Limits

Errors

Versioning

Next