Syften Reviewa fast, precise alerting tool with an unusually wide net

Syften is a keyword-alerting service for public online conversation. You write filters — a filter is a search rule, not just a word — and Syften checks new items from the sources it monitors against them, then delivers the matches wherever you tell it to. Its own summary: it monitors “the public web, Reddit, X/Twitter, Hacker News, forums, blogs, GitHub, YouTube, Slack communities, Bluesky, Mastodon, and other online communities.”

It started as a script. Its About page tells the story straight: Michał Mazurek left his job in April 2018, built a few products that did not work, and wrote a script to notify him whenever someone mentioned a particular phrase on Reddit. He shared it on Indie Hackers, the script turned out to be more popular than the product it was built to promote, and he switched to it full-time. The name comes from an Old English verb meaning to sift or strain. The first release, adding Hacker News support, is dated 28 May 2019.

That origin shows in the design. Syften reads as a tool built by someone who wanted alerts to be fast and precise, not a dashboard product retrofitted with alerting. The filter language is the centre of it, and its own positioning says as much: it contrasts itself with tools that “emphasize dashboards, brand analytics, and large social networks” and describes itself as “built for finding conversations you can act on quickly.”

It is bootstrapped, operated from Kraków, and the About page lists two sibling products — Aurilix for podcast monitoring and Clare Videre for AI visibility monitoring. We have not repeated any of its customer testimonials as fact here, because vendor-selected quotes are not evidence, but the profile they describe — developer tools, SaaS founders, open-source communities — matches the product.

Syften's source list is its strongest single feature, and its FAQ publishes it in full rather than as a “N+ platforms” marketing count. Eighteen entries: the public web, Reddit, X/Twitter, Indie Hackers, Hacker News, GitHub, Product Hunt, the Stack Exchange family, forums, Lobste.rs, Dev.to, Steemit, various Slack communities, newsletters, YouTube, podcasts, Bluesky and Mastodon.

The documentation then does something rarer: it says what is read from each one and how often. Reddit is fetched live from a logged-out perspective, and edits to items are not tracked. GitHub is checked hourly and covers issue comments, pull-request review comments and commit comments — explicitly not repository code. Stack Exchange and X run up to fifteen minutes behind. YouTube is checked at least once a day, and the docs volunteer that “the completeness of our results is at the mercy of the YouTube attention-grabbing algorithm” and that Syften does not analyse video contents. Publishing the weak spots alongside the strong ones is a good sign about a vendor.

The public-web scraper is newer, added in June 2026, and it is a different thing from community monitoring — Lucene query syntax rather than Syften's filter syntax, with `domain:`, `url:`, `title:`, and the two operators worth the price of entry on their own, `added:` and `removed:`. Those let you alert on a phrase appearing on or disappearing from a page, which is how you find out that a competitor has quietly changed its pricing or dropped you from a comparison table.

Now the retirements, because a source list is only half the story. Syften shut its Quora scraper down on 17 October 2025, and its Facebook Group scraper in August 2024, both recorded in the changelog. LinkedIn has never been supported and the FAQ says so plainly: “No, unfortunately not.” GrowthHackers support was removed in 2022. None of this is hidden — it is all in a public, dated changelog, which is more than most vendors offer — but if your buyers are on LinkedIn or Quora, this is the paragraph that decides your purchase.

Most tools in this bracket give you a text box and a checkbox for exact match. Syften gives you a small query language, and it is the main reason experienced users stay.

The defaults are already better than most. Matching is case-insensitive, multiple bare terms are ANDed in any order, quoted strings are phrases, and — importantly — the matcher applies word-boundary logic by default. The docs work the example through: the filter “cat and” matches “I bought a cat, and so…” but not “I had a copycat and he…”. Domains are treated specially, matching subdomains and obfuscated forms like `example[.]com` — a thoughtful touch for anyone whose brand gets mentioned as a URL people are trying not to make clickable.

On top of that: `site:` to scope to a subreddit or a single Stack Exchange site, with multiple values ORed; `type:post` and `type:comment`; `title:`; `author:` and `replyto:` to follow specific people; `lang:`; `NOT` for exclusions; wildcards at the start or end of a term or phrase; backticks to force literal matching including punctuation; `//` comments; and variables, so a shared set of `site:` clauses can be defined once and reused across a dozen filters. For anyone maintaining thirty filters, that last one is the difference between a maintainable setup and a mess.

One honest caveat: the syntax is a real thing to learn, and this is a product whose documentation you should read before your trial rather than after. Syften has clearly noticed, because onboarding is now automated — its FAQ says that after signup it researches your company, competitors and product names and creates the initial monitoring setup, so “you do not need to write filters yourself to get started.”

Syften describes itself as an AI-filtered keyword monitoring tool, and it is worth being exact about what that means, because “AI filtering” means five different things across this category.

In Syften it is a second stage that runs after a keyword filter has already matched. The documentation: “After a filter matches an item, Syften can run an additional AI accept/reject check before notifications are sent.” You define the check yourself, inside the filter, as `$accept:"true if …; false otherwise."` The docs recommend keeping the prompt “simple and robotic” and flag a specific trap — writing “true only when the post is about X” will reject posts that mention your product in passing, which is usually not what you want.

Three details matter for evaluating it. First, it is opt-in per filter: “If a filter has no `$accept:'…'`, no AI analysis is performed.” Nothing is judged unless you asked for it. Second, it is available on the Standard and PRO plans only — the $29.95 Entry plan has no AI filtering at all. Third, rejection is not deletion: rejected matches stay in the archive and the API, and API responses carry the AI verdict, the rejection reason and an NSFW flag, so you can audit what the gate threw away. The RSS feeds take `?accepted=true` or `?accepted=false` for the same purpose.

That is a well-designed noise filter, particularly for the case it is built for: a product whose name is an ordinary English word. Syften's own worked example is a fictional product called Bridge, where the rule keeps “Has anyone used Bridge for API integrations?” and rejects “The bridge reopens after maintenance.” If that is your problem, this solves it directly and lets you inspect every decision.

What it does not produce is a ranking or a classification. There is no relevance score, no intent taxonomy, and no drafted response. The output is a boolean plus a reason. Syften also documents a `$brand:` operator, but it is honest about its status: it is “reserved for potential future deeper AI analysis and internal experiments” and “currently has no effect” on matching, verdicts, notifications or API responses. It should not be counted as a shipped capability today, by us or anyone else.

This is where Syften is comfortably wider than most tools at its price, and wider than ParseStream on every row.

Matches can go to Slack, email, RSS, Atom and JSON feeds, an API, or webhooks. The routing mechanism is a single good idea applied consistently: every filter can carry `$tag:` values, and every destination subscribes to a tag, so brand mentions go to one Slack channel and competitor mentions to another without duplicating filters. A special `all` tag catches everything, and the docs include a worked agency example where each client's filters carry their own tag.

Email is more configurable than the norm — immediate, hourly, every six hours, every twenty-four hours, or off, with hourly mail accumulated and sent on the hour and daily mail at 06:00 UTC. If there are no matches, no email is sent. Slack delivery has a terse mode and applies an NSFW heuristic immediately before sending.

The developer surface is real. The API is POST-based with bearer-token auth and covers matches, archive search, settings, account info and — the part that matters — filters, including `filters/set`, which replaces filter groups atomically. That makes keyword provisioning scriptable, which most monitoring tools do not allow. Webhooks and an MCP server are both on the PRO plan; the MCP endpoint publishes setup for Codex, Claude Code and VS Code and exposes a `preview_filter` tool returning lints, approximate archive hit counts and sample matches, with the honest caveat that it cannot preview X or YouTube add-on filters.

The archive deserves a mention of its own. Retention runs seven days on Entry, a month on Standard and unlimited on PRO, and API archive search is PRO-only with an allowance of 1,000 fetched items a month, counted even when filtering drops them from the response. X, YouTube and the retired sources are not in the searchable archive. The most useful consequence is at trial time: sign up and Syften immediately shows mentions from the last two months, answering “is anyone talking about us at all?” before you have configured anything.

Three published plans, in USD, billed monthly, with no annual discount and no toggle hiding a second price — we checked the page for a switch, a currency selector and a slider, and there is none. Entry is $29.95, Standard is $49.95, Syften PRO is $119.95, and a “Tailor made” tier is quote-only.

The plans meter two things: how many filters you can run, and how many results a day you receive. Entry gives 3 communities filters and 1 web filter, with 100 community results and 5 web results a day, and a 7-day archive. Standard gives 20 and 5, with 200 and 20 a day, a 1-month archive, Slack, AI filtering and API access. PRO gives 100 and 20, with 500 and 50 a day, an unlimited archive, webhooks and MCP. Because one filter can span the whole source list, filter counts are not directly comparable to per-platform keyword slots in other tools, and we have deliberately not done that arithmetic anywhere.

The thing to look at before buying is what the Entry plan does not include, because it is more than the filter count suggests: no Slack integration, no AI filtering, no API, no webhooks, no MCP, and a seven-day archive. At $29.95 that is email and RSS delivery of three filters. Most people evaluating Syften seriously are choosing between Standard and PRO, and the honest entry price for the product as it is marketed — AI-filtered, Slack-delivered — is $49.95.

Then the add-ons. YouTube monitoring costs an extra $20 a month per ten filters, and Syften explains why: obtaining the data is expensive. That is a reasonable explanation and a real cost. X/Twitter monitoring is also a paid add-on, and here the review has to stop short — its price is not published on the pricing section, the X monitoring page or anywhere else we could find. If X matters to your evaluation, ask before you compare totals, because the plan price is not the whole number.

Against that, the trial is one of the better ones in the category: fourteen days, on the top plan, with no credit card, and two months of historical mentions visible on the first day. That is a vendor confident that the product sells itself once you see your own data in it.

Developer-tool and open-source companies, first and most obviously. If the people who use your product file GitHub issues, answer questions on Stack Overflow, read Lobste.rs and Dev.to, and argue on Hacker News, Syften reaches all of it in one subscription and almost nothing else in this price bracket does.

Anyone whose product name is a common word. The `$accept` gate is built precisely for this, it is inspectable after the fact, and the documentation teaches you how to write the rule properly. This is a better answer to the common-word problem than a relevance threshold.

Teams that want alerts routed rather than collected. If your support lead should see bug reports, your founder should see buying-intent posts and your marketer should see competitor mentions, tag-based routing into separate Slack channels does that cleanly, and it is the same mechanism agencies use to keep clients apart.

Developers and automation-minded teams. A write-capable API, webhooks, RSS and JSON feeds, and an MCP server on the PRO plan add up to a monitoring tool you can build on rather than only log into.

Anyone who needs to watch web pages as well as conversations — pricing pages, changelogs, documentation, directories, competitor comparison tables — via the `added:` and `removed:` operators.

And anyone for whom latency genuinely matters. Live Reddit fetching with a sub-minute target is a real engineering commitment, and it is faster than what we offer.

Anyone whose buyers are on LinkedIn or Quora. Syften does not reach either, publishes that fact, and there is no tier that changes it. ParseStream covers Quora questions and answers and LinkedIn posts, with those keyword slots starting on its Pro plan.

Anyone who needs the mention ranked rather than gated. Syften's AI answers “should this reach me?” and stops. If your problem is that forty things reached you and you need to know which six to answer first and what kind of answer each wants, a boolean verdict does not help — you want a relevance score and an intent classification, and that is a different product.

Anyone who is not short of alerts but short of time to reply. Syften writes nothing. If the bottleneck in your week is composing responses rather than finding threads, no amount of filter precision touches it.

Teams that need named seats and per-user access. Syften publishes nothing about seats or multi-user accounts, so treat it as unknown and ask them directly before assuming either way.

Buyers who need annual billing or a purchase-order-friendly contract. Syften publishes monthly pricing only.

And anyone whose budget stops at $30 and who expects AI filtering and Slack for it — at Entry you get neither, and the plan that matches the product's own marketing is $49.95.

Use the fourteen days properly, and use them on PRO, which is what the trial gives you. That means webhooks, MCP and unlimited archive are all live during the evaluation and will disappear if you then buy Entry or Standard — decide deliberately which of them you were relying on.

Spend the first hour in the archive, not the filters. Two months of history are there on day one. Search your brand, your two closest competitors and the two phrases someone types when shopping for what you sell, and read what comes back. If the volume is thin everywhere, no monitoring tool fixes that. If it is concentrated somewhere you did not expect, that is the most valuable thing the trial will tell you.

Then write three filters, not thirty: your brand, one competitor, one buying-intent phrase. Add an `$accept` rule to whichever of the three is noisiest and read the rejected items in the feed with `?accepted=false` to see whether the gate is throwing away things you wanted. Auditing rejections is the part most people skip and the part that tells you whether the rule is right.

Check the sources you actually care about individually, because coverage is not uniform. If YouTube is on your list, remember it is a $20-a-month add-on per ten filters and that its recall depends on YouTube search. If X is on your list, get the add-on price in writing first.

Read the documentation before the trial rather than during it. It is short, it is well written, and the filter syntax is where the product's value is. An evaluation run with three bare keywords will underrate Syften considerably.

And judge it against the right question. Syften is not competing to be the tool that decides what to do about a mention — it is competing to be the tool that never lets one past. Evaluate recall and precision, not triage.