Actions and Filters

All hooks are namespaced tncfb3d_*. Group them by lifecycle stage.

Actions — Lifecycle

Hook

Args

When

tncfb3d_after_register_cpt

—

After CPT registration

tncfb3d_rest_routes

—

tncfb3d_license_cron

—

Monthly license re-check

Actions — Viewer rendering

Hook

Args

Where

tncfb3d_viewer_head

$post_id, $payload

Inside <head>

tncfb3d_viewer_body_start

$post_id, $payload

Just after <body>

tncfb3d_seo_body_content

$post_id

SEO body content

tncfb3d_viewer_body_end

$post_id, $payload

Just before </body>

Actions — Admin / metabox

Hook

Args

When

tncfb3d_before_save_meta

$post_id, $post

Before meta save

tncfb3d_save_meta

$post_id, $post

After meta save

tncfb3d_after_save_meta

$post_id, $post

After full save

tncfb3d_flipbook_created

$post_id

New flipbook published

tncfb3d_flipbook_updated

$post_id

Flipbook updated

tncfb3d_flipbook_trashed

$post_id

Trashed

tncfb3d_flipbook_deleted

$post_id

Permanently deleted

tncfb3d_admin_enqueue_scripts

$hook, $screen

Enqueue admin assets

tncfb3d_metabox_tab_content_{key}

$post, $meta, $schema

Render custom metabox tab

tncfb3d_metabox_after_tab_content

$key, $post, $meta

After each tab

tncfb3d_seo_admin_fields

$post, $meta

Add SEO admin fields

Actions — Settings & REST

Hook

Args

Description

tncfb3d_settings_saved

$clean

After settings save

tncfb3d_settings_integrations_after

$options

After integrations tab

tncfb3d_settings_tab_content_{key}

$options

Custom settings tab content

tncfb3d_before_serve_file

$flipbook_id, $file_type, $index

Before proxy serves a file

Actions — TTS

Hook

Args

Description

tncfb3d_tts_generate_batch

$flipbook_id, $provider, $voice, $batch_end

Cron batch handler

tncfb3d_text_extracted

$post_id

After PDF text extraction

tncfb3d_background_extract

$post_id

Background extraction cron

Filters — Config builder

The config builder is where every tncfb3d_config_* filter fires. Resolution order: per-flipbook override → global setting → schema default.

Filter

Description

tncfb3d_config_effective_values

Tweak resolved settings before output

tncfb3d_config_download_filename

Override download filename

tncfb3d_config_toolbar_keys

Limit which toolbar items appear

tncfb3d_config_toolbar

Modify the final toolbar object

tncfb3d_config_rtl_languages

Customize the RTL language list

tncfb3d_content_access

Gate page-level access at runtime

tncfb3d_config

Final JS config payload

tncfb3d_config_options

Secondary options object

tncfb3d_config_payload

Final {config, options} envelope

Filters — Frontend / shortcodes / blocks

Filter

Description

tncfb3d_viewer_access

Allow / deny viewer access

tncfb3d_viewer_url

Customize iframe src

tncfb3d_iframe_attributes

Iframe HTML attributes

tncfb3d_shortcode_output

Final shortcode HTML

tncfb3d_viewer_addon_config

Pass data to viewer addons

tncfb3d_embed_block_output

Embed block HTML

tncfb3d_link_block_output

Link block HTML

tncfb3d_image_link_block_output

Image-link block HTML

tncfb3d_block_editor_data

Block editor localization payload

Filters — CPT / admin

Filter

Description

tncfb3d_cpt_messages

CPT update messages

tncfb3d_cpt_args

CPT registration args

tncfb3d_cpt_columns

Admin list columns

tncfb3d_admin_localize_data

Admin JS localization

tncfb3d_metabox_tabs

Add / remove metabox tabs

tncfb3d_settings_tabs

Add / remove settings tabs

tncfb3d_meta_schema

Modify the entire meta schema

Filters — Settings / integrations

Filter

Description

tncfb3d_integration_fields

Add integration fields

tncfb3d_integration_keys

Recognized integration option keys

tncfb3d_settings_sanitize

Final sanitize pass

tncfb3d_ideas_url

Roadmap URL

tncfb3d_newsletter_form_action

Newsletter form endpoint

tncfb3d_brevo_api_key

Brevo newsletter API key

Filters — SEO

Filter

Description

tncfb3d_seo_title

Page / OG title

tncfb3d_seo_description

Meta description

tncfb3d_seo_canonical

Canonical URL

tncfb3d_seo_robots

Robots meta

tncfb3d_seo_og_image

OG image URL

tncfb3d_seo_schema

JSON-LD schema

tncfb3d_seo_head

Before SEO head output

Filters — REST proxy

Filter

Description

tncfb3d_serve_file_path

Intercept file path

tncfb3d_serve_headers

HTTP response headers

Filters — TTS / text extract

Filter

Description

tncfb3d_tts_voices

Voices for a provider

tncfb3d_trust_forwarded_for

Trust X-Forwarded-For for rate limiting

tncfb3d_extracted_text

PDF text after extraction

For practical examples, see Integration Recipes.