Connor Bulmer

AI Auto Alt Text Generator is a lightweight, privacy-conscious plugin that uses OpenAI vision-capable models (defaulting to GPT-5.4 nano, with GPT-5.4 mini and legacy GPT-4o mini options) to create meaningful, screen-reader-friendly alt text and SEO-friendly titles for your images. Whether you add a single image, bulk-process your library, or just want a one-click fix in the Media Library, the plugin handles it all – no manual effort required.
This solution is far cheaper than many alternatives because it cuts out the middle-person. You’ll just need to bring your own OpenAI API key.
<h3>✨ Key features</h3>
<ul>
<li>Automatic alt text on upload – set-and-forget accessibility.</li>
<li>Optional automatic image titles – improve SEO with descriptive titles.</li>
<li>One-click manual generation – “Generate Alt Text & Title” button in the Media Library.</li>
<li>Bulk update tool – batch-process existing images, including those that only have filename-based alt text, with a configurable pause between batches.</li>
<li>Prompt fine-tuning – supply site-wide context and optionally include the image file name.</li>
<li>Model selection – default to GPT-5.4 nano (fastest & cheapest) or switch to GPT-5.4 mini for higher quality; legacy GPT-4o mini and GPT-5 mini/nano remain available.</li>
<li>Image size & detail control – choose the resolution and level of visual detail sent.</li>
<li>Developer-friendly – filters and actions to customise prompts, models and output, plus optional outgoing webhooks.</li>
<li>WordPress Abilities API – registers a <code>generate-alt-text</code> ability (WordPress 6.9+/7.0) so core AI, agents and automation tools can generate alt text.</li>
<li>No extra servers – data flows only between your site and OpenAI; nothing is stored off-site.</li>
<li>Multilingual output – choose English (UK), English (US) or other popular languages. (English US is the default.)</li>
</ul>
<h3>🧭 Where to find the bulk tool</h3>
<ul>
<li>Tools → Bulk Alt Text Update</li>
<li>Media → Bulk Alt Text Update (shortcut that redirects to the Tools page)</li>
<li>Settings → Alt Text Generator includes a button linking straight to the bulk page</li>
</ul>
<h3>🧠 How it works</h3>
<ol>
<li>When an image is uploaded (or manually chosen), the plugin creates a temporary public URL for that image.</li>
<li>It sends the image – plus optional context such as the parent post title, your custom site context and the file name – to your selected OpenAI vision model.</li>
<li>OpenAI returns a concise description.
<ul>
<li>Alt text is stored in WordPress’ native <code>_wp_attachment_image_alt</code> field.</li>
<li>(Optional) The returned title is stored as the attachment post title.</li>
</ul>
</li>
<li>Nothing is cached or stored on OpenAI’s side; only the final strings live in your database.</li>
</ol>
<h3>Settings overview</h3>
<ul>
<li>OpenAI API Key – Required to connect to OpenAI.</li>
<li>OpenAI Model – GPT-5.4 nano (default), GPT-5.4 mini, or legacy GPT-4o mini / GPT-5 mini / GPT-5 nano.</li>
<li>Image Size to Send – Thumbnail, Medium, Large, or Full.</li>
<li>Image Detail Quality – ‘Low’ or ‘High’ (Low uses fewer tokens).</li>
<li>Bulk batch size – Number of images per batch (lower values reduce rate-limit risk).</li>
<li>Site Context – Optional free-form prompt guidance (brand voice, niche, etc.).</li>
<li>Send Image File Name – Include file name in the prompt for extra context.</li>
<li>Automatically Generate Title – Add descriptive titles alongside alt text.</li>
<li>Use full context for image titles – When enabled, title generation includes site context and file name (uses more tokens).</li>
<li>Bulk optimiser delay (seconds) – Pause between batches during bulk runs.</li>
<li>OpenAI request timeout (seconds) – Max wait time for OpenAI responses (10–120s) to reduce timeout failures on slower hosts.</li>
<li>Output Language – Default English (US). Choose English (UK) for British spellings or another popular language; outputs (alt text and titles) will be generated in the selected language.</li>
<li>Webhook URL & signing secret – Optionally POST generated alt text/titles to an external endpoint (with an optional HMAC-SHA256 signature) for automation and logging.</li>
</ul>
<h3>Developers</h3>
The plugin is extensible via standard WordPress hooks, an outgoing webhook, and the WordPress Abilities API.
Filters
<ul>
<li><code>aatg_alt_text_prompt</code> ( $prompt, $post_ID, $context ) – customise the alt-text prompt.</li>
<li><code>aatg_image_title_prompt</code> ( $prompt, $post_ID, $context ) – customise the title prompt.</li>
<li><code>aatg_openai_request_payload</code> ( $payload, $context, $messages ) – customise the full OpenAI request (model, messages, reasoning effort).</li>
<li><code>aatg_generated_alt_text</code> ( $alt_text, $post_ID ) – filter alt text before it is saved.</li>
<li><code>aatg_generated_title</code> ( $title, $post_ID ) – filter the title before it is saved.</li>
<li><code>aatg_is_low_quality_alt</code> ( $is_low, $alt, $post_ID ) – control which existing alt text the bulk tool regenerates.</li>
<li><code>aatg_webhook_payload</code> ( $payload, $post_ID, $result ) – customise the outgoing webhook body.</li>
<li><code>aatg_supported_image_extensions</code> ( $extensions ) – customise which image formats are sent to OpenAI (default: PNG, JPEG, GIF, WebP).</li>
</ul>
Actions
<ul>
<li><code>aatg_after_alt_text_generated</code> ( $post_ID, $alt_text )</li>
<li><code>aatg_after_title_generated</code> ( $post_ID, $title )</li>
<li><code>aatg_after_generation</code> ( $post_ID, $result )</li>
</ul>
Outgoing webhook
Set a Webhook URL under Settings → Integrations & Webhooks to receive a non-blocking JSON POST after each generation. If a signing secret is set, requests include an <code>X-AATG-Signature: sha256=…</code> header (HMAC-SHA256 of the body) so your endpoint can verify authenticity.
WordPress Abilities API
On WordPress 6.9+ the plugin registers the ability <code>ai-auto-alt-text/generate-alt-text</code> (input: <code>attachment_id</code>) so WordPress core AI, agents, MCP servers and automation tools can generate alt text programmatically. Execute it with <code>wp_get_ability( 'ai-auto-alt-text/generate-alt-text' )->execute( array( 'attachment_id' => 123 ) )</code>.
<h3>External services</h3>
This plugin connects to the OpenAI API to generate alt text and (optionally) image titles.
<ul>
<li>Endpoint: <code>https://api.openai.com/v1/chat/completions</code></li>
<li>When called:
<ul>
<li>On image upload (automatic)</li>
<li>Via “Generate Alt Text & Title” button in Media Library (manual)</li>
<li>Via Tools → Bulk Alt Text Update (bulk)</li>
</ul>
</li>
<li>Data sent: image URL, optional file name, optional site context, optional parent post title</li>
<li>Terms: <a href="https://openai.com/policies/terms-of-use" rel="nofollow ugc">https://openai.com/policies/terms-of-use</a></li>
<li>Privacy: <a href="https://openai.com/policies/privacy-policy" rel="nofollow ugc">https://openai.com/policies/privacy-policy</a></li>
</ul>
If you configure a Webhook URL, generated alt text/titles (and the image URL) are also sent to that endpoint you control.

AI Auto Alt Text Generator

Automatically generates alt text and image titles for your WordPress media uploads with selectable OpenAI models (defaulting to GPT-5.

Luis Ruiz

Bubuku I Code

Bubuku Media Library helps content and marketing teams audit, monitor and optimize images in WordPress. Track file sizes, identify missing alt text, export reports, receive email summaries and connect AI assistants through MCP.
New in version 1.3.0: Bubuku Media Library includes an MCP Server that allows compatible AI assistants and developer tools to interact with your WordPress Media Library through a secure endpoint with role-based permissions.
You can:
<ul>
<li>Sort the Media Library by file size to easily identify large files.</li>
<li>Filter images that don’t have alternative text (alt text).</li>
<li>Use size-based filters (for example: optimal size, medium size, large size) to prioritize which images to optimize first.</li>
<li>Run a Bulk Action in the Media Library to calculate file sizes for existing uploads.</li>
<li>Export CSV reports including file size, format (MIME type), URL, alt text, image date, post title and post URL — ideal for audits or sharing with your team.</li>
<li>See a summary of your Media Library in a dashboard widget, including how many images are heavy or missing alt text.</li>
<li>Configure weekly or monthly email reports so you can monitor the optimization status of your images without logging into WordPress.</li>
<li>Connect MCP-compatible AI assistants to your Media Library using role-based permissions and configurable abilities.</li>
</ul>
More information (in Spanish) about how the plugin works: <a href="https://www.bubuku.com/blog/como-saber-reducir-peso-imagen-atributo-alt-seo/" rel="nofollow ugc">How to know if we have to reduce weight to the image and Alt SEO attribute</a>
<h3>AI & MCP Integration</h3>
Bubuku Media Library includes a built-in MCP Server that allows compatible AI assistants and development tools to securely interact with your WordPress Media Library.
Available MCP abilities include:
<ul>
<li>Listing media library attachments.</li>
<li>Reviewing image metadata and alt text coverage.</li>
<li>Exporting media audits to CSV.</li>
<li>Accessing media library summary metrics.</li>
<li>Triggering reports and diagnostics.</li>
<li>Managing media accessibility workflows.</li>
</ul>
Each ability can be enabled or disabled individually and restricted to a minimum WordPress role. This allows you to safely connect AI assistants like Claude Desktop, Codex, Cursor and other MCP-compatible clients to audit images, review missing alt text, generate reports and automate media management workflows, while keeping permissions under your control.
Typical use cases include:
<ul>
<li>Finding images without alt text.</li>
<li>Exporting media audits for content reviews.</li>
<li>Checking image size distribution.</li>
<li>Generating accessibility reports.</li>
<li>Integrating WordPress media workflows with AI assistants.</li>
<li>Automating repetitive media library review tasks.</li>
</ul>
<h3>Quick Start</h3>
<ol>
<li>
From your server (SSH), move the plugin folder to the plugins directory:
wp-content/plugins/bubuku-media-library/
</li>
<li>
Activate the plugin via the WordPress admin or using WP-CLI:
wp plugin activate bubuku-media-library
</li>
<li>
(Optional) Run the bulk action in Media > Library to calculate file sizes for existing images.
</li>
</ol>
<h3>Evaluate results</h3>
Recommended Tools 
– <a href="https://developer.chrome.com/docs/lighthouse/" rel="nofollow ugc">Lighthouse</a> (in Chrome DevTools) — Analyze image weight and format, as well as the use of alternative text (ALT). 
– <a href="https://www.webpagetest.org/" rel="nofollow ugc">WebPageTest</a> — Check how images affect real-world load times. 
– <a href="https://squoosh.app/" rel="nofollow ugc">Squoosh</a> — Compare visual quality and file size savings when optimizing images. 
– <a href="https://wave.webaim.org/" rel="nofollow ugc">WAVE Accessibility Tool</a> — Verify whether images are missing ALT attributes or if the alternative texts are descriptive.
Evaluation Guidelines 
– Identify images without ALT text or with excessive file size before running external tests. 
– After replacing large images or adding ALT text, repeat your evaluations to confirm improvements. 
– Evaluate both new and existing content — not only the most recent uploads. 
– Define an internal size limit (for example, 200 KB per image) and monitor it regularly. 
– Keep in mind that accessibility also affects SEO and overall user experience.
<h3>SUPPORT</h3>
Need help or have a suggestion? 
Please use the <a href="https://wordpress.org/support/plugin/bubuku-media-library/" rel="ugc">official WordPress.org Support Forum</a> for any issues related to the plugin.
Official Website 
For additional information or to get in touch with the development team, please visit our <a href="https://www.bubuku.com/" rel="nofollow ugc">official website</a>.
Like the plugin? 
Please <a href="https://wordpress.org/support/plugin/bubuku-media-library/reviews/?filter=5" rel="ugc">leave a 5-star review</a> and help others discover Bubuku Media Library.
<h3>ABOUT BUBUKU_CODE</h3>
We develop custom solutions for WordPress focused on performance, accessibility, and maintainable code. Our work includes plugins, themes, and integrations designed to improve the daily workflow of marketing and content teams.

Bubuku Media Library

Una idea excelente, imprescindible en toda biblioteca de utilidades WPO para la correcta optimización de las webs.

Además, tiene aún algunas posibilidades de crecimiento como mostrar en el frontend a los usuarios conectados como admin las imágenes con un outline en caso de no tener definido el alt img:not([alt]) o quizás también leer el tamaño de las imágenes y mostrar los códigos de color según su peso, etc.

Como digo, una idea excelente, de un excelente programador.

Imprescindible en la biblioteca de utilidades WPO

A tool that helps outline big images or those that don't have the alt attribute. Very useful if you are improving a site's WPO or looking after better accessibility.

It does what it says, and it does it right.

Great WPO resource

Muy útil para gestión del día a día de las imágenes

Tus archivos de imágenes bajo control

Manage image file size, alt text and AI-powered media audits in your WordPress Media Library to improve performance, accessibility and SEO.

AI Auto Alt Text Generator vs Bubuku Media Library