BigCommerce API + MCP vs Ecwid by Lightspeed

BigCommerce API + MCP

Published rate limits per plan, with X-Rate-Limit-Time-Reset-Ms on every 429. Storefront MCP is beta, switched on per store, has no back-office tools and documents no tool annotations.

Ecwid by Lightspeed

The REST API has 40 access scopes, a published limit of 600 requests a minute per token with Retry-After on a 429, field selection through responseFields, and Markdown docs with an llms.txt index. Tokens never expire, there is no test mode or idempotency key, API access needs a paid plan, and carts are built only in the browser.

BigCommerce API + MCP

1. Give the agent a store-level API account with only the scopes the task needs, and delete it when done
2. On a 429, wait X-Rate-Limit-Time-Reset-Ms before retrying
3. Expect up to 10 minutes after a store owner enables the MCP before the URL answers
4. The MCP stops at a checkout URL. Payment happens in the shopper's browser
5. Point a coding agent at the docs MCP at https://docs.bigcommerce.com/_mcp/server

Ecwid by Lightspeed

1. Send the token as Authorization: Bearer to https://app.ecwid.com/api/v3/{storeId}. Tokens in the query string stopped working in March 2025
2. Use the secret token server-side only. The public token reads enabled products and places orders that are not marked paid
3. Add responseFields, for example total,items(id,name,price), to keep responses small, and page with offset and limit (maximum 100)
4. Stay under 600 requests a minute per token and wait the Retry-After seconds on a 429. Repeated calls with a bad token get the token and IP blocked for longer
5. Work in a separate test store. There is no test mode, and POST /orders writes a real order with no idempotency key
6. After changing an app's scopes, uninstall and reinstall it, then replace the stored tokens. The old ones stop working