Synq REST API Reference: Endpoints, Auth, and Error Codes

The Synq REST API gives you programmatic access to every resource on the platform — products, orders, inventory, channels, integrations, and more. All communication happens over HTTPS using JSON. Before making your first request, read the Authentication page to learn how to obtain and attach your credentials.

Base URL

Every API request targets the following base URL:

https://api.synq.io

All resource endpoints are prefixed with /api/v1/. Webhook endpoints delivered by Synq to your infrastructure use the /unified/ prefix instead.

Request Format

Send all request bodies as JSON and include the Content-Type header on any request that carries a body:

Content-Type: application/json

Requests with a body larger than 10 MB are rejected with 413 Content Too Large.

Response Format

Every response body is JSON. Successful responses contain the requested or mutated resource. Error responses follow a consistent shape:

{
  "error": "A human-readable description of what went wrong."
}

Authentication

Every protected endpoint requires a valid Bearer token in the Authorization header. The token encodes your identity, tenant, and organization so that each request is automatically scoped to your data. See the Authentication guide for the full details.

API Resources

Products

Create and manage your product catalog, variants, and attributes.

Orders

Place, track, fulfill, and return orders across all your channels.

Inventory

Query stock levels, reserve units, and adjust inventory in real time.

Channels

Configure the sales channels that feed orders into Synq.

Integrations

Connect third-party platforms and manage OAuth callbacks.

Organization

Manage your organization profile, members, and roles.

Settings

Read and update tenant-level configuration and preferences.

Audit

Query the immutable audit log for all actions taken in your tenant.

HTTP Status Codes

Synq uses standard HTTP status codes. The table below covers every code you may encounter.

Code	Meaning	When you see it
`200 OK`	Request succeeded	The resource was retrieved or updated successfully.
`201 Created`	Resource created	A new resource was persisted. The response body contains the created object.
`202 Accepted`	Request queued	The request was accepted for asynchronous processing (for example, a bulk import). Poll the relevant status endpoint for the result.
`400 Bad Request`	Invalid request	The request body is malformed, a required field is missing, or a value fails validation. Inspect the `error` field for details.
`401 Unauthorized`	Missing or invalid token	The `Authorization` header is absent or the Bearer token has expired or is invalid. Refresh your token and retry.
`403 Forbidden`	Insufficient permissions	Your token is valid but your role does not permit this action, or a required claim is missing from your token.
`404 Not Found`	Resource missing	The requested resource does not exist or is not visible to your tenant.
`429 Too Many Requests`	Rate limit exceeded	You have sent too many requests in a short window. Wait for the number of seconds in the `Retry-After` response header before retrying.
`500 Internal Server Error`	Server error	An unexpected error occurred on Synq’s side. Retry the request using exponential backoff. If the problem persists, contact support.

Rate Limiting

The API enforces a sliding-window rate limit of 100 requests per minute per IP address. Every response includes the following headers so you can track your usage:

Header	Description
`X-RateLimit-Limit`	The maximum number of requests allowed in the current window.
`X-RateLimit-Remaining`	The number of requests you have left in the current window.
`Retry-After`	Seconds to wait before retrying (only present on `429` responses).

When you exceed the limit, the API returns 429 Too Many Requests. Wait for the number of seconds indicated in the Retry-After header before sending your next request.

​Base URL

​Request Format

​Response Format

​Authentication

​API Resources

Products

Orders

Inventory

Channels

Integrations

Organization

Settings

Audit

​HTTP Status Codes

​Rate Limiting

Base URL

Request Format

Response Format

Authentication

API Resources

HTTP Status Codes

Rate Limiting