Hydrogen SEO – AI SEO Plugin for Schema, Sitemaps, llms.txt & AEO
| 开发者 | sheeshlabs |
|---|---|
| 更新时间 | 2026年9月11日 03:27 |
| PHP版本: | 7.4 及以上 |
| WordPress版本: | 7.1 |
| 版权: | GPLv2 or later |
| 版权网址: | 版权信息 |
详情介绍:
Beta software. Hydrogen SEO is new. Every feature below works and is covered by automated tests, but it has not had the years of field testing the established SEO plugins have. Try it on a staging site first if that matters to you.
Hydrogen SEO is a lightweight, AI-powered SEO plugin for WordPress. It writes your meta titles and meta descriptions, generates schema markup, fills in image alt text, and audits your site for the on-page issues that hold rankings back — all from a fast, modern dashboard and directly inside the block editor.
It is built for how search works now. Alongside the metadata and structured data Google reads, it gives you an llms.txt editor and clean, machine-readable output, so the systems that answer questions from web content have something unambiguous to work from.
[youtube https://youtu.be/LGMvSnxsXu0]
Hydrogen AI: an SEO agent inside your dashboard
Ask for what you want in plain language — "write meta descriptions for every post missing one", "add FAQ schema to this page", "find and fix broken internal links" — and Hydrogen AI does the work through the plugin's own tools. It asks before anything it cannot undo, shows you every change it makes, and you can stop it at any point.
Hydrogen AI lives in two places: the plugin dashboard for site-wide work, and a tab in the editor's SEO Settings sheet scoped to the post you are editing.
AI writing tools
- AI meta titles and meta descriptions — click the AI button beside the field, get several suggestions with character counts, pick one and it fills the field
- AI social titles and descriptions for Facebook / Open Graph and X (Twitter)
- AI image alt text for a single image or in bulk across your media library
- AI content generation and rewriting for SEO
- AI featured image generation
- AI-assisted schema (structured data) for your business details
- SEO titles and meta descriptions with template variables for posts, pages, custom post types, taxonomies and archives
- Schema markup (JSON-LD): Article, Product, FAQ, HowTo, Recipe, Course, Event, Local Business, Breadcrumbs and more
- XML sitemaps
- Robots meta controls per post, plus a built-in robots.txt editor
- Open Graph and X (Twitter) card previews, so you see the share card before you publish
- Google search result (SERP) preview as you type
- Redirection manager with 301 and 302 support
- One-click import from Rank Math, Yoast SEO, SureRank, All in One SEO, The SEO Framework, Slim SEO and SEOPress, with preview and undo
- Homepage SEO settings and canonical URLs
- llms.txt editor — publish crawl and usage guidance for large language models, the emerging convention for AI answer engines
- Structured data and metadata written to be machine-readable, so your pages are unambiguous to anything parsing them
- Server-rendered output — nothing about your SEO depends on JavaScript running
- Clean XML sitemaps with images and accurate lastmod dates, so crawlers and answer engines see what changed and when
- Title and meta description templates, separator and capitalization
- noindex / nofollow / noarchive rules per post type and taxonomy
- Homepage SEO, social defaults, Twitter handle, default share image and social profiles
- Organization / Person knowledge graph, website name and alternate name
- robots.txt content and sitemap options
- Every post, page, category and tag with its own SEO title, description, focus keyword, canonical URL, robots, social title / description / image and schema type
- Redirect rules, including Yoast Premium, SureRank Business, All in One SEO Pro, Slim SEO and SEOPress PRO redirects
wp hydrogen-seo migrate run rank-math --dry-run.
Site audits and health checks
The dashboard scores your site across seven areas — crawlability, performance, mobile, security, content structure, schema markup and technical health — with a clear list of what to fix first. Site-wide audits find duplicate titles and descriptions, keyword cannibalisation, orphan pages, broken internal links and metadata that is too long or too short.
Fast and clean
- Modern React dashboard
- Heavy assets load on demand, so wp-admin stays quick
- No front-end JavaScript and no extra front-end requests — the SEO output is server-rendered markup
- Every screen is backed by the plugin's own REST API
安装:
- In your WordPress admin, go to Plugins → Add New and search for "Hydrogen SEO", or upload the
hydrogen-seofolder to/wp-content/plugins/ - Activate the plugin through the Plugins menu
- Follow the short setup wizard
- To turn on the AI features, open Hydrogen SEO → API Key and connect your free hydrogenseo.com account
- To use Hydrogen AI, switch on AI Abilities and connect the agent — see the FAQ below for exactly what that creates and stores
常见问题:
Do I need an account to use the plugin?
No. SEO titles and meta descriptions, schema markup, XML sitemaps, robots.txt, redirections, social previews and the site health checks all work out of the box. Only the AI features — AI meta descriptions, alt text, content, images and Hydrogen AI — need a free API key from hydrogenseo.com.
Is Hydrogen SEO free?
The plugin is free and GPL licensed. The AI features run on the Hydrogen SEO API, which gives you free credits on signup; heavier use needs a paid plan. Nothing in the plugin stops working when you run out of credits — only the AI generation pauses.
How do the AI suggestions work in the editor?
Open the Hydrogen SEO panel while editing a post or page. Six fields have a small AI button beside them: the SEO title and meta description, the Open Graph title and description, and the X (Twitter) title and description. Click it and you get several suggestions with character counts. Choose one and it fills the field — you can still edit it afterwards, and nothing is published until you save.
What is Hydrogen AI and what can it change?
Hydrogen AI is a chat agent that reads and edits your site's SEO through the plugin's own registered tools: page metadata, structured data, sitemaps, robots rules, redirects, alt text and featured images. It runs under a policy you choose. By default it asks for confirmation before anything destructive, and you can set it to ask before every write or to run read-only checks. It cannot act at all until you switch on AI Abilities and connect it.
What is an application password, and why does Hydrogen AI need one?
Hydrogen AI runs on the Hydrogen SEO service, so the service needs a way to call back into your site to read and change SEO data. WordPress's built-in application passwords are that mechanism — a revocable credential, separate from your login password, that never gives anyone access to your admin screens. When you connect the agent, the plugin creates one application password named Hydrogen SEO Agent for the WordPress user doing the connecting, and sends it to the service over HTTPS so it can authenticate its calls back to your site. Any earlier credential with the same name is deleted first, so only one ever exists. The service verifies the credential by calling your site before it stores anything, and it stores it encrypted. See the "Privacy" and "External services" sections for the specifics.
How do I revoke the agent's access?
Two ways, and either is enough:
- In the plugin, open Hydrogen SEO → Hydrogen AI and disconnect. The plugin deletes the Hydrogen SEO Agent application password from your site and clears the stored connection.
- In WordPress, go to Users → Profile → Application Passwords and revoke Hydrogen SEO Agent directly.
What is llms.txt and why does it matter?
llms.txt is a file at the root of your site that states how your content may be crawled and used by AI systems, in the way robots.txt does for search engines. It is a proposed convention, not a ratified standard, and honouring it is up to each crawler. Hydrogen SEO gives you an editor for it so the file exists and says what you want it to say.
How do I add schema markup without writing JSON-LD?
Pick a schema type in the Schema screen or in the post's SEO panel and fill in the fields; the plugin outputs valid JSON-LD for you. Article, Product, FAQ, HowTo, Recipe, Course, Event, Local Business and Breadcrumbs are all supported, and the AI can draft your business details for you.
Can I import my settings from Rank Math, Yoast SEO, SureRank, All in One SEO, The SEO Framework, Slim SEO or SEOPress?
Yes. Go to Hydrogen SEO → Tools → Import SEO Data, pick the plugin, click Preview to see exactly what would change, then Start import. Global settings, per-post and per-term SEO data and redirects are imported, including data from Rank Math PRO, Yoast SEO Premium, SureRank Business, All in One SEO Pro, Slim SEO Pro and SEOPress PRO. Every import can be undone from the same screen.
Is Hydrogen SEO compatible with other SEO plugins?
It works alongside other plugins, but running two SEO plugins that both output titles, meta tags or schema can produce duplicate output. Import your data with Tools → Import SEO Data and let it deactivate the old plugin once the import completes, so Hydrogen SEO is your only SEO plugin.
Will this slow my site down?
No. The plugin adds no front-end JavaScript for its SEO output, and the admin dashboard loads its heavy assets only when needed.
What are the requirements?
WordPress 6.7 or higher, PHP 7.4 or higher, and a modern browser with JavaScript enabled in the admin. Application passwords — needed only for Hydrogen AI — require HTTPS and must not be disabled by a security plugin.
Where is my data sent?
Only to the Hydrogen SEO API, and only when you actively use an AI feature or run the agent. The "External services" and "Privacy" sections below list exactly what is sent, when, and what is stored.
更新日志:
0.0.20
- New: Import SEO Data now also migrates from All in One SEO (free and Pro, including the
aioseo_posts/aioseo_termstables and Pro redirects), The SEO Framework (branding rebuilt as templates, per-object redirects), Slim SEO (and Slim SEO Pro schema builder) and SEOPress (and SEOPress PRO robots.txt and redirect manager). Their smart tags are converted, module toggles and inherit-switches are honoured, and conditional / pass-through redirects are reported instead of copied. - Fix: templates whose only unsupported tag sat between two separators (
%title% | %page% | %site_name%) now collapse to a single separator.
- New: Import SEO Data (Tools > Import SEO Data, and
wp hydrogen-seo migrate). Migrates global settings, per-post-type/taxonomy templates, robots, social defaults, knowledge-graph schema, robots.txt, redirections and per-post/term meta from Rank Math, Yoast SEO and SureRank, including their Pro/Premium/Business data when present. Smart tags are converted to Hydrogen tags, values that only mirrored a global default are left to inherit, runs are resumable, previewable (dry run), idempotent and can be rolled back, and the source plugin can be deactivated once the import completes. - Fix: term SEO fields saved from the taxonomy metabox were stored under the post meta prefix but read by the frontend under a term prefix, so term titles, descriptions, robots and canonicals never applied. Both prefixes are now read.
- Fix: Open Graph / Twitter images saved as URLs were treated as attachment IDs on the frontend and never rendered; the frontend now resolves URL,
_idcompanion or bare ID. - Fix: the metabox stored
twitter_card_typewhile the frontend readtwitter_card; both keys are now honoured. - Fix: the template tags
%separator%,%category%,%categories%,%tags%and%post_type%advertised in the settings UI are now actually replaced on the frontend.
- Performance: the plugin read a dozen of its own settings options one at a time on every public page view, and on a site that had not saved a settings screen none of them existed yet, so each read cost a database query that found nothing. They are now fetched in a single primed query, and in none at all once the settings have been saved or a persistent object cache is present — seven extra queries per page view down to one on a fresh install and zero on a configured site
- Smaller download: the plugin's pre-build React/TypeScript sources were being packaged alongside the compiled output, adding roughly 1.6 MB to every install and every update. The release now ships the compiled assets only
- No functional or interface changes
- Security: AI generation, embedding and site-wide bulk endpoints (content, metadata, embeddings, featured-image, bulk alt-text and their stats/settings) now require the plugin's administrator capability. Previously they inherited an edit_posts class capability, which let lower roles (contributor/author) spend the site's AI credits and, in the unbounded bulk paths, write SEO meta to posts they could not edit.
- Security: the SEO Analysis settings endpoint now requires the administrator capability instead of edit_posts.
- Security: media-library alt-text generation (single and bulk) now checks edit_post on each attachment, so a user can no longer generate or overwrite alt text on attachments they do not own.
- Security: the featured-image upload endpoint now requires the upload_files capability, matching WordPress core.
- Security: fixed a stored/reflected XSS in the document . Titles are now escaped at the output sink, so markup in a post title or search query can no longer break out of the tag.
- Security: automatic slug-change redirections are now only recorded for users who can manage redirects, preventing a lower-privilege user from registering a site-wide redirect by renaming their own content.
- Security: a redirection rule with an empty match path is no longer treated as a site-wide catch-all.
- Hardening: similarity search no longer returns content from password-protected posts, restricts searches to public post types, and caps how many posts a single request may process.
- Plugin name, short description and directory tags rewritten so the plugin is findable for what it actually does — AI SEO, schema, XML sitemaps, llms.txt and answer engine optimization (AEO)
- Beta status moved out of the plugin title and into the top of the description, where it is actually read
- Compatibility updated: tested up to WordPress 7.1
- New section explaining what answer engine optimization means and which parts of it the plugin covers, plus an explicit note that AI visibility monitoring runs on the connected account rather than in the plugin
- No functional changes
- Fixed: no canonical URL was output on posts, pages, category, tag, author and date archives. The plugin replaces WordPress core's canonical tag, but only the homepage printed a replacement, so every other page shipped without one. Canonical output is now handled in one place that covers every context, honours a per-page canonical override, and points paged archives at themselves instead of page one. Search results and 404s are intentionally left without a canonical.
- Smart tags everywhere: schema URL, date, number, textarea and image fields with dynamic defaults now use the variable editor (type @ to insert tags) in the dashboard and the editor
- Fixed broken default tags and added the missing %author_url% variable; older saved values are migrated automatically
- Date-time, telephone and email schema fields now render correctly (Event, Organization, Local Business and more)
- One clean header: page description, page actions and a single Save button that appears only when there is something to save, plus an unsaved-changes prompt before leaving a page
- Schema settings save on demand instead of auto-saving every edit
- Steadier layout: one scroll container per page, pinned sidebar, lighter editor sheet that closes on outside click, compact social previews
- Removed the placeholder Analytics, Instant Indexing and SEO Analyzer pages; Help & Support now opens the support site
- Under the hood: 250+ automated tests, static analysis at maximum level and stricter coding standards across the plugin
- Setup wizard is two steps instead of three: the Site Analysis step is gone, along with the scan endpoint behind it
- Finishing setup now always records that it is complete, so the wizard stops reappearing after you leave the last screen
- Hydrogen AI: a chat agent inside the plugin that reads and changes your site's SEO through Hydrogen SEO's own tools — page metadata, structured data, sitemaps, robots rules, redirects, alt text and featured images — and asks before anything it cannot undo
- Hydrogen AI lives in the dashboard and as a second tab in the editor's SEO Settings sheet, scoped to the post you are editing
- 87 WordPress Abilities registered for agents, gated behind an explicit switch, a domain lock and the manage_options capability
- New site-wide audits: duplicate titles and descriptions, keyword cannibalisation, orphan pages, broken internal links, metadata lengths
- Connecting the agent needs only your Hydrogen SEO API key and confirms before creating its application password
- The older per-field AI buttons, AI featured image section and AI tools page are retired in favour of Hydrogen AI
- Onboarding improvements
- Clearer consent wording and a working privacy policy link in the setup wizard
- AI suggestions in the editor: the SEO title, meta description and social fields now have an AI button that offers several options with character counts — choose one and it fills the field
- Fixed AI features that generated results but never applied or displayed them
- Fixed AI requests timing out before the generation finished
- Fixed AI featured image generation and setting a generated image as the featured image
- Removed the AI Content Assistant panel in favour of the per-field AI buttons
- Removed placeholder sample data from the dashboard so every number shown is your site's own
- Long generated text no longer overflows its input; added loading, empty and error states across the dashboard and the editor panel
- Errors that previously failed silently (saving SEO settings, loading schema fields, content analysis) are now reported in the interface
- Internal link suggestions are now provided by the separate Hydrogen SEO Pro add-on
- Various layout, spacing and consistency fixes
- Completely redesigned setup wizard with a new immersive look and a smoother step-by-step flow
- Streamlined the WordPress admin menu — full navigation now lives inside the plugin dashboard's own sidebar
- Faster admin dashboard: heavy visual assets are now loaded on demand instead of up front
- Fixed setup wizard layout issues: unnecessary scrolling, button placement, and focus states
- Various UI polish and stability improvements across the dashboard and block editor
- New Hydrogen SEO "Balloon" brand mark across the admin menu, dashboard, block editor, and WordPress.org listing (banner and icon)
- Refreshed loading and onboarding animations to use the animated logo
- Rebranded the plugin to Hydrogen SEO
- Output JSON-LD schema markup with WordPress default escaping for safe script-context rendering
- Registered plugin settings with a statically verifiable prefixed option name
- Removed sitemap search-engine pinging and the XSL stylesheet
- Documented external services in the readme
- Sanitized stored schema data and escaped JSON-LD output for script context
- Fixed General Settings not saving
- Initial release
- AI-powered content analysis
- Content optimization features
- Modern React-based dashboard
- REST API integration