Audio Summary Generation and WordPress Post Update - n8n Workflow

Content creators and bloggers seeking to add audio versions to their articles.
SEO specialists looking to enhance content accessibility and time-on-page.
Users who need practical, multi-step n8n templates involving external APIs like Eleven Labs.
Anyone interested in integrating AI text summarization and text-to-speech capabilities into their publishing pipeline.

This comprehensive n8n workflow provides a powerful solution for automating content enrichment on WordPress sites. By leveraging the integration capabilities of the n8n node system, this automation fetches existing article content, sends it to an OpenAI model for summarization or transcription, and utilizes the Eleven Labs API to generate high-quality audio. Unlike standard n8n templates, this flow handles custom authentication for external services and manages binary file transfer directly to the WordPress media library, ensuring the entire process—from text to published audio block—is fully automated. This demonstrates the versatility of the n8n platform for complex, media-heavy content operations.

The n8n workflow operates through the following steps:

1. Start: The process begins with a manual n8n trigger, initiating the sequence.


2. Configuration: A 'Set' n8n node defines the necessary base URL for the target WordPress site.


3. Data Retrieval: The 'Retrieve WordPress Article' n8n node fetches the content of a specified post ID from WordPress.


4. AI Processing: The article content is passed to the LangChain 'Generate Summary or Transcription' n8n node, which uses the linked 'OpenAI Chat Model' (GPT-4o Mini) to produce a concise summary or full transcription, as defined by the user prompt.


5. Text-to-Speech (TTS): The generated text is sent via the 'Generate Speech' n8n node (an HTTP Request configured for Eleven Labs) to convert the text into an MP3 binary file. Custom HTTP authentication is required here.


6. Media Upload: The 'Upload MP3' n8n node, another HTTP Request configured to use the WordPress REST API, uploads the MP3 file to the WordPress media library. It utilizes the article slug for the filename.


7. Post Update: Finally, the 'Update WordPress Post' n8n node inserts a standard WordPress audio block shortcode at the beginning of the original article content, referencing the newly uploaded media ID. This completes the n8n workflow, making the audio instantly available to site visitors.

1. Import: Copy the entire n8n workflow JSON and paste it into your n8n instance's workflow editor.


2. WordPress Credentials: Configure the 'Retrieve WordPress Article' and 'Update WordPress Post' n8n node connections with your WordPress API credentials (Username/Password or Application Passwords).


3. OpenAI Credentials: Set up the 'OpenAI Chat Model' n8n node with your OpenAI API key.


4. Eleven Labs Credentials: The 'Generate Speech' n8n node uses custom HTTP authentication. You must create a new generic credential named 'Custom Auth account' (or similar) with a header defined as xi-api-key and your Eleven Labs API key as the value.


5. URL Configuration: Update the 'settings' n8n node with your actual site_url.


6. Testing: Manually adjust the postId in the 'Retrieve WordPress Article' n8n node to target a specific test article before running the n8n trigger.

When clicking ‘Test workflow’ (Manual Trigger n8n trigger): Initiates the entire automation flow for testing and manual runs.
settings (Set n8n node): Essential for defining global variables, specifically siteurl, which is required for the final WordPress media API calls.
Retrieve WordPress Article (WordPress n8n node): Fetches the full content and metadata for a specific post ID (1032) to be processed by the AI.
OpenAI Chat Model (LangChain n8n node): Specifies the model (gpt-4o-mini) used for language processing. This model is linked to the chain n8n node for actual prompting.
Generate Summary or Transcription (LangChain n8n node): The core AI logic. It feeds the raw article HTML ({{ $json.content }}) into the prompt to generate the audio script.
Generate Speech (HTTP Request n8n node): Converts the text summary into binary audio data (MP3) by calling the Eleven Labs API (/v1/text-to-speech/voiceid). It uses custom authentication and defines the model ID (elevenmultilingualv2).
Upload MP3 (HTTP Request n8n node): Handles the critical binary file transfer. It uploads the resulting MP3 to the WordPress REST API media endpoint, setting the appropriate Content-Disposition header using the article slug.
Update WordPress Post (WordPress n8n node): Updates the original article by dynamically constructing and inserting the