Summary

mam_codex_manager (includes/app-settings/codex-manager.php) is a tooling-side settings discovery API. It walks the registered content classes, their settings categories, and their per-field schemas, producing a structured catalog that admin tooling can consume — for example, an admin-side documentation generator, a settings-search UI, or an API for external editors.

It is not user-facing. End-users never see codex output directly.

Public surface

Output shape mirrors what app_settings() returns from each content class:

array(
    array(
        'category'    => 'login',
        'title'       => 'Require Login?',
        'variable'    => 'require_login',
        'type'        => 'yes-no',
        'id'          => 'tsl-require_login',
        'environment' => 'global',
        // augmented fields:
        'content_class' => 'local_app_login_button',
        'help_desc'     => '... (from mam_settings_set_help_desc filter)',
    ),
    ...
)

Hook involved

When to use it

• Building an admin search UI — let admins search “what setting controls the geofilter radius?”
• Auto-generating docs — produce a Markdown / HTML reference of every setting from source
• External integrations — an external editor that needs to know what settings exist
• Refactor diagnostics — enumerate settings to find orphans

When NOT to use it

• In the phone-data hot path. get_all_settings() walks every content class; it’s expensive. Cache the result aggressively if you call it from a request-time path.
• For per-request setting reads. Use mam_app_settings_get_setting for those.
• For determining “does this setting exist?” at runtime. Use metadata_exists() or check the option directly — codex is for tooling, not gating.

Gotchas

• Codex catalog is rebuilt on demand. It enumerates the global $local_app_content registry plus walks each class’s app_settings() method. Heavy.
• Content classes that omit app_settings() appear in the catalog but contribute no entries.
• mam_codex_update_settings action is fired by codex itself when the catalog is built — sibling plugins listening here can mirror the catalog into their own indexes.
• Help descriptions are lazy — they require a mam_settings_set_help_desc subscriber to populate. Without one, the help_desc field is empty.

Related articles

• Settings cascade overview
• Content classes overview
• Hook: mam_app_settings_get_setting

Metadata