ButterCMS vs Webflow

ButterCMS

The Read and Write APIs have a public OpenAPI 3.1 file, Markdown docs and a status page with no incident since October 2025. The Write API is a paid add-on from the $249 plan, capped at 2,000 or 5,000 calls a month. Writes answer 202 with no identifier, support rotates tokens, and the terms are an undated website document.

Webflow

The Data API has a public OpenAPI 3.1 spec with 140 operations, scoped OAuth and site tokens, and CMS items that stay drafts until a separate publish call. The MCP server loads 34 multi-action tools and can't create new localised CMS items. The free plan holds 50 CMS items, and the activity log needs the $2,500 Team plan.

ButterCMS

1. End every path with a slash. A missing slash returns a 301, and the vendor counts the redirect and the retry as two API calls
2. Send the write token only as Authorization: Token <token>. The auth_token query parameter works for reads only
3. On page creation send every field key of the page type, with empty strings for fields left blank
4. A 202 means queued, not saved. Read the entry back with preview=1 to confirm, and check a slug exists before retrying a create
5. Call the REST API directly for writes. The JavaScript SDK 3.0.3 has list, retrieve and search methods only

Webflow

1. Send the token as Authorization: Bearer to https://api.webflow.com/v2. Ask for cms:read and cms:write only, plus sites:write if the task publishes
2. Create or update items first, then call Publish Items or Publish Site. An item with isDraft true and a lastPublished date is live with unpublished changes
3. Stay under 60 requests a minute on Starter and Basic and 120 on Premium, read X-RateLimit-Remaining, and wait for Retry-After on 429
4. Page item lists with limit (maximum 100) and offset, and filter with filter[<fieldSlug>][<operator>], up to 10 terms
5. Upload an asset in two steps (create the asset with a file hash, then POST the bytes to the presigned URL). Write localised content with the item's cmsLocaleId