33. Filter Reference | SEO Forge - Rank Higher with AI-Powered SEO

All WordPress filters that SEO Forge hooks into, plus custom filters provided by SEO Forge for developer extensibility.

WordPress Filters Used by SEO Forge

Filter	Class	Method	Priority	Description
`robots_txt`	`SEOFORGE_Robots_Txt`	`custom_robots_txt`	10	Custom robots.txt content
`sanitize_file_name`	`SEOFORGE_Image_Seo`	`clean_filename`	10	Clean uploaded image filenames
`admin_body_class`	`SEOFORGE_Core`	`add_body_class`	10	Adds `sf-admin` class to admin body
`document_title_parts`	`SEOFORGE_AB_Testing`	(closure)	10	Swaps title for A/B variant B
`attachment_fields_to_edit`	`SEOFORGE_Image_Seo`	`alt_text_reminder`	10	Missing alt text warning

SEO Forge Custom Filters

Filter	Parameters	Description
`seoforge_template_variables`	`$vars` (array)	Add custom template variables to the meta template system
`seoforge_resolve_template`	`$output`, `$post_id`	Resolve custom variables during meta template rendering

Using Filters in Your Code

// Modify the title after SEO Forge processing
add_filter( 'document_title_parts', function ( $title_parts ) {
    $title_parts['title'] .= ' (' . date( 'Y' ) . ')';
    return $title_parts;
}, 20 );

// Modify robots.txt after SEO Forge
add_filter( 'robots_txt', function ( $output, $public ) {
    $output .= "nUser-agent: GPTBotnDisallow: /n";
    return $output;
}, 20, 2 );

// Prevent filename cleanup for specific file types
add_filter( 'sanitize_file_name', function ( $filename ) {
    // Preserve original filenames for PDF uploads
    if ( pathinfo( $filename, PATHINFO_EXTENSION ) === 'pdf' ) {
        return $filename;
    }
    return $filename;
}, 5 ); // Priority 5 runs before SEO Forge's 10

// Add custom variables to the meta template system
add_filter( 'seoforge_template_variables', function ( $vars ) {
    $vars['{{reading_time}}'] = 'Estimated reading time';
    return $vars;
} );

add_filter( 'seoforge_resolve_template', function ( $output, $post_id ) {
    $content = get_post_field( 'post_content', $post_id );
    $word_count = str_word_count( wp_strip_all_tags( $content ) );
    $minutes = max( 1, ceil( $word_count / 200 ) );
    return str_replace( '{{reading_time}}', "{$minutes} min read", $output );
}, 10, 2 );

—