ButterCMS vs Directus

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.

Directus

The built-in MCP server works under the connecting user's permissions, supports OAuth limited to the MCP endpoint and blocks deletes unless an administrator allows them. Since version 12 a licence check caps the free Core tier at 3 Studio seats, 25 collections and 5 flows, and the default tool list carries about 79 KB of instructions.

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

Directus

1. Connect with OAuth or an Authorization: Bearer header. Don't put the token in the URL as ?access_token=, where it can be logged
2. Use /mcp?tool_mode=registry when the client loads every tool definition. Default mode sends each tool's full instructions, about 79 KB in total
3. Read the schema tool before writing. Item payloads are untyped objects, so field names and types come only from the data model
4. Publish a version with POST /versions/{id}/promote over REST. The MCP items tool refuses system collections such as directus_versions
5. Count translation and junction tables against the 25-collection Core limit before creating collections