Synth Antispam – AI Comment Spam Protection

No. Visitors see no CAPTCHA, puzzles or extra fields. Synth checks the comment in the background.

Every site starts with an included allowance of AI spam checks, with no card required. Sites that need more checks can upgrade to a paid plan — see https://wordpress.synth.locker/pricing.

AI classification pauses until the allowance resets or you upgrade. Comments follow the fallback you selected — they continue through your normal WordPress moderation (default) or are held for review — so your site never stops accepting comments.

Keyword filters look for known words, domains or patterns. Synth analyzes the intent and context of the comment, which helps it recognize rewritten and human-looking promotional spam without maintaining rule lists.

Yes. Synth never touches a comment another plugin or a moderator already marked as spam or trash, never changes a comment whose status a moderator has already changed, and never publishes a comment held for review, so it can run alongside your existing moderation setup. A held comment it finds to be spam still goes to the Spam folder (in strict mode it stays in the queue).

Yes. Synth can be used on its own for WordPress comment spam protection, or alongside Akismet and other moderation plugins. If another plugin has already marked a comment as spam or trash, Synth leaves it unchanged.

No. Synth never automatically deletes comments or moves them to Trash. Spam goes to the Spam folder (or the moderation queue in strict mode), where you can restore it.

It adds no scripts to your pages. Submitting a comment waits for the service for up to 2 seconds; the verdict follows in the background.

Yes — turn on strict mode.

Comments follow the fallback you chose: they continue through your normal WordPress moderation (default) or are held for review.

Checks are on for a new installation; a site updated from an earlier version sees a one-time notice offering to turn them on. Flamingo, by the author of Contact Form 7, keeps a copy of every submission, including those marked as spam. The visitor waits while the check runs — usually a few seconds, rarely more than about eight. If no verdict arrives in time, "When the service is unreachable" decides: let your site decide sends the email as usual; hold marks the submission as spam. When your monthly checks are used up, submissions always go through unchecked — "When the monthly check quota is used up" applies to comments only. A decision already made by Contact Form 7 or another plugin, such as Akismet or reCAPTCHA, is left as it is and costs no check.

The first submission from an address is checked as usual. Once Synth classifies a submission as spam, further submissions from the same address are held without a check for 10 minutes; if spam keeps coming from that address, the window grows up to one hour. No more than three submissions from one address are checked at the same time. Held submissions are marked as spam by Contact Form 7 and listed in the held-submissions journal (Contact → Held submissions), where the button "Not spam — deliver" sends the form's email as if it had never been held. If your site is behind a proxy or CDN that does not pass the visitor's address on to WordPress, all visitors share one address, so after a spam submission the window applies to everyone. The filters synth_wp_cf7_address_cooldown (seconds, 0 turns it off) and synth_wp_cf7_address_concurrent (0 turns it off) adjust both limits.

Into the held-submissions journal: Contact → Held submissions (Settings → Held submissions while Contact Form 7 is not active). Every submission the plugin holds is listed there for 7 days with its subject, sender, the reason it was held and the start of its message, then deleted automatically. The journal keeps up to a limit of held submissions; when it is full, further held submissions are still marked as spam by Contact Form 7 but not kept, and the journal shows how many. "Not spam — deliver" sends the email the form would have sent, to its usual recipient; the automatic reply to the sender and file attachments are not sent again. Delivering a submission also lets the same sender through again: the plugin forgets its verdict on that text and ends the waiting period for their address.

The form's own spam message — Synth does not replace it. Contact Form 7 shows the text set in Contact → your form → Messages → "Submission was referred to as spam", which by default reads "There was an error trying to send your message. Please try again later." It is the same message a visitor sees when Akismet or reCAPTCHA holds a submission, so you decide its wording once, for every reason. A person held by mistake is told to try again rather than that the message was sent.

Comments, pingbacks and trackbacks from the comment form, REST API and XML-RPC, and WooCommerce product reviews submitted through the review form on the product page. Commenters and reviewers with an already-approved comment or review are trusted and skipped. With Contact Form 7 checks on, also every Contact Form 7 submission, except those from logged-in moderators.

Yes, with a key per site or a network-level key.

No. Apart from the Get a site key button, it sends no requests, and WordPress decides on every comment exactly as it would without the plugin.

It stays, so reinstalling keeps your checks. Enable "Delete the site key when the plugin is deleted" to remove it.

Mention Synth in your privacy policy, including what is sent and how long it is kept, with the 24-hour verdict retention and the indefinite retention of training copies (see "External services"). You need a lawful basis for processing commenter data.