--- title: Citelayer® Hooks & Filters Reference — WordPress Developer Guide — citelayer® url: https://citelayer.ai/docs/hooks-filters/ date: 2026-02-25 --- # Citelayer® Hooks & Filters Reference — WordPress Developer Guide EXCERPT: Customize every aspect of Citelayer® output with WordPress hooks and filters. Full reference with code examples. SEO-TITLE: Citelayer® Hooks & Filters Reference — WordPress Developer Guide Citelayer® exposes a comprehensive set of WordPress filters that let you customize every output — from structured data schemas to llms.txt content and protocol responses. Each filter follows standard WordPress conventions and receives well-documented parameters. All filters listed on this page are available since version 0.3.0. For endpoint-level documentation, see the REST API Reference. Schema Filters These filters let you modify the JSON-LD structured data that Citelayer® injects into your pages. Use them to add properties, change types, or extend the schema graph. For an overview of how Citelayer® generates schema markup, see Schema & Structured Data. citelayer_organization_schema Filters the Organization schema array before Citelayer® outputs it as JSON-LD. Use this filter to add social profiles, contact information, or change the organization type. Parameters Parameter Type Description $schema array Organization schema data including @type, name, url, and all configured properties. Source: Schema.php line 312Since: 0.3.0 add_filter( 'citelayer_organization_schema', 'my_customize_organization_schema' ); function my_customize_organization_schema( $schema ) { // Add social profile links. $schema['sameAs'] = array( 'https://twitter.com/yourhandle', 'https://www.linkedin.com/company/yourcompany', 'https://github.com/yourorg', ); // Add a contact point. $schema['contactPoint'] = array( '@type' => 'ContactPoint', 'telephone' => '+1-800-555-0199', 'contactType' => 'customer service', 'areaServed' => 'US', ); // Change to a more specific organization type. $schema['@type'] = 'Corporation'; return $schema; } citelayer_website_schema Filters the WebSite schema array before output. Use this filter to customize the search action, add alternative names, or modify site-level structured data. Parameters Parameter Type Description $schema array WebSite schema data including @type, url, name, publisher, and potentialAction. Source: Schema.php line 364Since: 0.3.0 add_filter( 'citelayer_website_schema', 'my_customize_website_schema' ); function my_customize_website_schema( $schema ) { // Add an alternative site name. $schema['alternateName'] = 'YS'; // Add a custom SearchAction targeting a specific search page. $schema['potentialAction'] = array( '@type' => 'SearchAction', 'target' => array( '@type' => 'EntryPoint', 'urlTemplate' => home_url( '/search/{search_term_string}' ), ), 'query-input' => 'required name=search_term_string', ); return $schema; } citelayer_article_schema Filters the Article or BlogPosting schema for individual posts. This filter receives both the schema array and the WP_Post object, so you can conditionally modify schema based on post type, category, or custom fields. Parameters Parameter Type Description $schema array Article/BlogPosting schema data for the current post. $post WP_Post The WordPress post object being rendered. Source: Schema.php line 434Since: 0.3.0 add_filter( 'citelayer_article_schema', 'my_customize_article_schema', 10, 2 ); function my_customize_article_schema( $schema, $post ) { // Use TechArticle for posts in the "tutorials" category. if ( has_category( 'tutorials', $post ) ) { $schema['@type'] = 'TechArticle'; $schema['proficiencyLevel'] = 'Beginner'; } // Add a custom citation from a meta field. $citation = get_post_meta( $post->ID, '_article_citation', true ); if ( $citation ) { $schema['citation'] = $citation; } // Add word count. $schema['wordCount'] = str_word_count( wp_strip_all_tags( $post->post_content ) ); return $schema; } Content & Protocol Filters These filters let you customize the content Citelayer® generates for AI-facing protocols. For feature overviews, see llms.txt, WebMCP, and UCP. citelayer_llmstxt_content Filters the llms.txt content before Citelayer® outputs it. Important: this filter receives an array of lines (strings), not a single string. Each element represents one line in the final output. Parameters Parameter Type Description $content array Array of content lines (strings). Each element becomes one line in the output. Source: LLMS_TXT.php line 262Since: 0.3.0 add_filter( 'citelayer_llmstxt_content', 'my_customize_llmstxt' ); function my_customize_llmstxt( $content ) { // Add a custom section at the end. $content[] = ''; $content[] = '## API Documentation'; $content[] = '- [REST API Reference](https://yoursite.com/docs/api/)'; $content[] = '- [Webhooks Guide](https://yoursite.com/docs/webhooks/)'; // Remove lines containing a specific URL. $content = array_filter( $content, function ( $line ) { return strpos( $line, '/internal-draft/' ) === false; } ); // Re-index the array after filtering. $content = array_values( $content ); return $content; } citelayer_webmcp_context Filters the full WebMCP context data before Citelayer® serves it at /.well-known/mcp/context.json. Use this filter to add custom capabilities, modify the endpoint list, or inject metadata. See WebMCP for protocol details. Parameters Parameter Type Description $context array Full WebMCP context data including site info, capabilities, and endpoints. Source: WebMCP.php line 145Since: 0.3.0 add_filter( 'citelayer_webmcp_context', 'my_customize_webmcp_context' ); function my_customize_webmcp_context( $context ) { // Add a custom capability. if ( isset( $context['capabilities'] ) ) { $context['capabilities']['custom_search'] = true; } // Add custom metadata. $context['metadata'] = array( 'support_email' => 'dev@yoursite.com', 'api_version' => '2.1', ); return $context; } citelayer_ucp_discovery_response Filters the UCP (Unified Commerce Protocol) discovery response before Citelayer® returns it. Use this filter to add custom capabilities or modify shop information. See UCP Commerce Protocol for protocol details. Parameters Parameter Type Description $response_data array UCP discovery response including protocol, version, shop, and capabilities. Source: UCP_Discovery.php line 115Since: 0.3.0 add_filter( 'citelayer_ucp_discovery_response', 'my_customize_ucp_discovery' ); function my_customize_ucp_discovery( $response_data ) { // Add custom shop metadata. $response_data['shop']['industry'] = 'Electronics'; $response_data['shop']['currency'] = 'EUR'; $response_data['shop']['shipping_zones'] = array( 'EU', 'US', 'UK' ); // Override capabilities if your integration supports them. $response_data['capabilities']['product_browsing'] = true; return $response_data; } Compatibility Filters Citelayer® automatically detects third-party SEO plugins and manages feature conflicts. These filters let you override detection results and conflict resolution. See SEO Plugin Compatibility for background. citelayer_detected_seo_plugins Filters the array of detected SEO plugin slugs. Use this filter to force-add a custom or private SEO plugin that Citelayer® doesn’t detect automatically, or to exclude a plugin from detection results. Parameters Parameter Type Description $plugins array Array of detected plugin slugs (e.g., array( 'yoast-seo', 'rank-math' )). Source: Compatibility.php line 380Since: 0.3.0 add_filter( 'citelayer_detected_seo_plugins', 'my_customize_seo_detection' ); function my_customize_seo_detection( $plugins ) { // Force-add a custom SEO plugin so Citelayer® recognizes it. $plugins[] = 'my-custom-seo-plugin'; // Exclude a plugin from detection (treat it as not installed). $plugins = array_diff( $plugins, array( 'all-in-one-seo-pack' ) ); return array_values( $plugins ); } citelayer_feature_conflicts Overrides conflict detection for specific feature and plugin combinations. Citelayer® checks whether a feature (like schema output) conflicts with an active SEO plugin. Use this filter to force a feature on or off regardless of the default detection logic. Parameters Parameter Type Description $conflicts bool true if Citelayer® detected a conflict, false otherwise. $feature string The feature being checked (e.g., 'schema', 'meta_tags'). $plugin string The plugin slug that triggered the conflict check. Source: Compatibility.php line 601Since: 0.3.0 add_filter( 'citelayer_feature_conflicts', 'my_override_feature_conflicts', 10, 3 ); function my_override_feature_conflicts( $conflicts, $feature, $plugin ) { // Allow Citelayer® schema output even when Yoast SEO is active. if ( 'schema' === $feature && 'yoast-seo' === $plugin ) { return false; } // Force-disable a feature for a specific plugin. if ( 'meta_tags' === $feature && 'rank-math' === $plugin ) { return true; } return $conflicts; } Best Practices Always return the filtered value. Every filter callback must return the modified (or unmodified) data. Forgetting the return statement silently breaks output. Use the correct number of accepted arguments. Filters like citelayer_article_schema and citelayer_feature_conflicts pass multiple parameters. Declare the argument count in add_filter() (e.g., 10, 2 or 10, 3). Place filter code in your theme’s functions.php or a custom plugin. Avoid editing Citelayer® files directly — updates will overwrite your changes. Test with WP_DEBUG enabled. Schema output errors appear in the debug log and help you catch malformed data early. Validate schema changes. After modifying schema filters, test your pages with Google’s Schema Validator to ensure valid JSON-LD. Related Documentation REST API Reference — Endpoint documentation for programmatic access Schema & Structured Data — How Citelayer® generates JSON-LD llms.txt for WordPress — AI-readable site summaries WebMCP Context Discovery — Machine-readable site capabilities UCP Commerce Protocol — Unified Commerce Protocol for WooCommerce Markdown Content Endpoint — Per-post markdown output SEO Plugin Compatibility — Conflict detection and resolution citelayer_bot_analytics_cleanup_days Controls bot visit retention. $days (int), default 90. add_filter( 'citelayer_bot_analytics_cleanup_days', function( $days ) { return 180; } ); citelayer_product_feed_max_items Max products in XML feed. $max (int), default 1000. add_filter( 'citelayer_product_feed_max_items', function( $max ) { return 2500; } );