Prismic vs Sanity

Prismic

The hosted MCP server stages every write as a draft in a release, cannot delete, and publishes only when a user with the Publisher role asks. Write tokens for the Migration, Asset and Types APIs have no scopes, no OpenAPI file was found, writes are limited to one request a second, and the acceptable use policy forbids access by scripts.

Sanity

Sanity publishes 26 OpenAPI specs covering 225 operations, and its hosted MCP server saves edits to drafts or release versions, with publishing as a separate call. The Content Lake does not run schema validation on API writes, and custom roles that limit a token to one dataset or document type are sold only on Enterprise plans.

Prismic

1. Ask a repository Administrator to activate Prismic MCP in Settings first. Activation can take several minutes, and each environment has its own setting
2. Call list_repositories, then get_custom_type or get_shared_slice for the empty content template before create_document
3. Create a release with create_release and write into it. Call publish_release only on an explicit request, because a publish cannot be undone through MCP
4. For the Migration API send Authorization: Bearer <write token> and a repository header, one page a request, one request a second, and keep each returned id for later PUT calls
5. Upload media first (upload_asset or POST to https://asset-api.prismic.io/assets) and reference the asset id in image and media link fields

Sanity

1. Pin a static dated version in every URL, such as v2025-02-19. Omitting apiVersion in @sanity/client falls back to v1.
2. Validate documents against the schema yourself before an HTTP write, or run sanity documents validate afterwards. The Content Lake does not enforce schema rules.
3. Back off on 429 for mutations yourself. @sanity/client retries queries five times but never retries mutations. The limit is 25 mutations a second per IP.
4. Over MCP, call create_version before patch_documents when editing inside a release, then patch the returned version ID with the same releaseId.
5. Use GROQ projections and slices to size results. MCP query responses are limited to 64 KiB, and a blocked Free project answers 402 with plan_limit_reached.