Auto-generate WordPress SEO drafts and featured images with n8n + Claude

Webhook receives brief → Claude generates article and SEO metadata → Imagen 4 creates featured image → WordPress draft → Slack team notification

Who

Content teams, solo publishers, developers, and agencies managing multiple WordPress sites

You get

Send an article brief and automatically receive a WordPress draft with SEO metadata, featured image, and Slack notification

You need

n8n · slack

Steps

1. Initialize config and authenticate

   Fill the CONFIG node with: WORDPRESS_URL, DEFAULT_CATEGORY_ID, AUTHOR_ID, SLACK_CHANNEL (optional), TONE_GUIDE, STYLE_GUIDE, IMAGE_STYLE_PROMPT, and WEBHOOK_SECRET (optional Bearer token). The VALIDATE AUTH node checks the Authorization header: if WEBHOOK_SECRET is empty or the header matches Bearer + secret, execution continues; otherwise returns 401.

2. Generate article content

   PREPARE INPUT merges prompt, category_id, tone_guide, and style_guide from the webhook body with CONFIG defaults. BUILD PROMPT assembles the full prompt including tone guide, style guide, and brief. GENERATE ARTICLE CONTENT calls the Anthropic API (model claude-sonnet-4-20250514, max_tokens=4000). PARSE ARTICLE uses JavaScript to extract title, content (HTML), excerpt, tags, seo_title, seo_description, focus_keyword, image_subject, and affiliate_flag from Claude's JSON response.

   Execution prompt · Source text。BUILD PROMPT node claude_prompt field; variables substituted before passing to GENERATE ARTICLE CONTENT node

   Copy prompt

   =You are a content writer.
   
   TONE GUIDE:
   {{ $json.tone_guide }}
   
   STYLE GUIDE:
   {{ $json.style_guide }}
   
   Write an article based on this brief: {{ $json.prompt }}
   
   Requirements:
   - Follow the tone guide and style guide precisely
   - SEO title under 60 characters
   - Meta description under 155 characters
   - Tags should reference only tools and concepts actually discussed in the article
   
   Return ONLY a valid JSON object (no markdown, no code fences), with these exact fields:
   {
     "title": "...",
     "content": "...full HTML article body using h2, p, ul/li tags...",
     "excerpt": "...two sentence summary...",
     "tags": ["...", "..."],
     "seo_title": "...under 60 chars...",
     "seo_description": "...under 155 chars...",
     "focus_keyword": "...single most important keyword phrase...",
     "image_subject": "...one sentence describing a visual scene for the featured image...",
     "affiliate_flag": "...note tools where affiliate links would be natural, or false if none..."
   }

3. Generate featured image (optional)

   CHECK IMAGE ENABLED tests if CONFIG.ENABLE_IMAGE_GENERATION equals true. If false, skip this stage and set media_id to 0. If true, GENERATE IMAGE calls the Google Generative Language API (model imagen-4.0-fast-generate-001), concatenating IMAGE_STYLE_PROMPT and image_subject as the prompt with aspectRatio=16:9. DECODE IMAGE decodes the returned base64 to binary, generating the filename from focus_keyword. UPLOAD IMAGE TO WORDPRESS uploads via the WordPress REST API. SET IMAGE ALT TEXT sets the focus_keyword as alt text. SET MEDIA ID saves the media ID. MERGE IMAGE RESULT combines both branches.

4. Create WordPress draft

   SPLIT TAGS splits the tags array into individual items. UPSERT TAG calls the WordPress REST API per tag to create or retrieve tag IDs (neverError=true prevents errors on duplicates). COLLECT TAG IDS aggregates all tag IDs. CREATE WORDPRESS POST creates a draft post with title, HTML body, excerpt, category, tags, featured media ID, and author.

5. Set Rank Math SEO (optional)

   SET RANK MATH SEO updates the post's meta fields via WordPress REST API: rank_math_focus_keyword, rank_math_title, rank_math_description. Prerequisite: Rank Math plugin installed, and the provided mu-plugin code placed in wp-content/mu-plugins/rank-math-rest.php to expose these fields to REST.

   Setup guidance · Source text。Save as WordPress wp-content/mu-plugins/rank-math-rest.php

   Copy prompt

   <?php
   // Register Rank Math SEO meta fields for REST API access.
   add_action( 'rest_api_init', function () {
       $fields = [
           'rank_math_focus_keyword',
           'rank_math_title',
           'rank_math_description',
       ];
       foreach ( $fields as $field ) {
           register_post_meta( 'post', $field, [
               'show_in_rest'      => true,
               'single'            => true,
               'type'              => 'string',
               'sanitize_callback' => 'sanitize_text_field',
               'auth_callback'     => function () {
                   return current_user_can( 'edit_posts' );
               },
           ] );
       }
   } );

6. Slack notification and webhook response

   CHECK SLACK CHANNEL tests if SLACK_CHANNEL is non-empty. If set, SLACK NOTIFICATION sends a Slack message with draft title, edit link, tags, and affiliate flag. RESPOND TO WEBHOOK returns JSON: {success: true, post_id, draft_url}.

   Execution prompt · Source text。SLACK NOTIFICATION node text field

   Copy prompt

   =📝 *New draft ready for review*
   *Title:* {{ $("PARSE ARTICLE").item.json.title }}
   *Edit:* {{ $("CONFIG").item.json.WORDPRESS_URL }}/wp-admin/post.php?post={{ $("CREATE WORDPRESS POST").item.json.id }}&action=edit
   *Tags:* {{ $('PARSE ARTICLE').item.json.tags.join(', ') }}
   *Affiliate:* {{ $('PARSE ARTICLE').item.json.affiliate_flag }}

You are setting up an n8n workflow: receive article briefs via Webhook, call Claude to generate SEO-structured HTML articles, optionally generate Imagen 4 featured images, create WordPress drafts, and send Slack notifications. Please confirm:
1. n8n instance URL and access
2. Anthropic API key
3. WordPress site URL + Application Password (Settings → Users → Application Passwords)
4. Enable image generation? If yes, Google AI API key (aistudio.google.com, project needs Imagen 4 access)
5. Enable Slack notifications? If yes, Slack OAuth2 app and channel ID
6. Use Rank Math SEO? If yes, install Rank Math plugin and place the provided PHP code in wp-content/mu-plugins/
7. CONFIG node parameters: WORDPRESS_URL, DEFAULT_CATEGORY_ID, AUTHOR_ID, TONE_GUIDE, STYLE_GUIDE

Once confirmed, import the template from n8n.io/workflows/16216, link credentials, and update CONFIG.