Meta Box MCP across the core plugin and its extensions

Auditing a Meta Box site you have inherited

Sites built on Meta Box often mix field groups a developer registered in code with groups someone later added in MB Builder, and the builder screen only manages the second kind. A Meta Box MCP session can map both without changing anything. metabox-check-setup lists which extensions are loaded and counts field groups by source, php against db, so the first answer already tells you how much of the model lives in theme or plugin files.

From there, metabox-list-field-groups gives each group's key, source, post types and field count, and metabox-get-field-group-schema with include_fields returns the full definition for PHP and database groups alike. Ask the agent for a table of every group, where it is defined and which post types it applies to. On most inherited sites that table is the documentation nobody wrote, and it is all reads, so the Read Only profile is enough.

Taking over a group that was registered in PHP

The edit abilities refuse PHP groups with metabox_php_registered, so a client who wants to manage a coded group in MB Builder needs a database copy. Because Meta Box keys values by field id in the object's meta, not by group, a copy that keeps every field id reads the values already stored. Read the PHP group's schema, create a database group from it under a new group key with the same field ids and types, then remove the PHP registration in code.

Do the swap on staging. Until the code registration is gone, both groups describe the same fields, and how the editor presents that duplication is something to check on the actual site rather than assume. Open a post that already has values and confirm they appear once, in the new group, before the change reaches production.

• Check the field types first with metabox-get-field-type-schema; Meta Box types such as single_image, image_upload, key_value and fieldset_text each carry their own options.
• Keep field ids exactly as they were. A renamed id starts empty and leaves the old value behind as an orphaned meta key.
• If the group stores into a custom table through MB Custom Table, stop: the value abilities do not read or write those tables.

Settings pages and partial writes

A settings page created through MB Settings Page keeps all its values in one wp_options row named after the page id unless an option_name overrides it. metabox-write-values with target type settings merges the fields you send into that row, so writing a new phone number does not wipe the opening hours stored next to it. Use the page id from metabox-list-settings-pages as the target id.

Writes report per field. A batch of five values where one field id is wrong can save the other four, so the agent should read the results array, not just the call status. Passing field_group_key makes the ability check every key against that group first, which turns a typo into an early failure instead of a stray meta key on the post.