Mention Monitor: Hacker News, Mastodon, Bluesky, YouTube

$2 per 1,000 mentions ($1.20 on the Gold tier), no start fee, no API key, no login. Every post is delivered once.

Give it what to watch and run it on a schedule: keywords on Hacker News, hashtags or accounts on any Mastodon instance, accounts on Bluesky, and YouTube channels or playlists. Each run delivers only the public posts that appeared since the previous check, as one normalized row per post with author, text, link, time and engagement, so a brand, a product, a competitor or a topic can be followed across the open web from one dataset, into Slack, a sheet, or an agent.

All four sources are read through their official public interfaces: the Hacker News search API, the Mastodon public API of each instance, Bluesky's public AppView, and YouTube's channel feeds. No scraping of HTML, no accounts, no keys.

What you get

Mention rows (kind: "mention"), newest first within each watch:

{
  "kind": "mention",
  "source": "hackernews",
  "watch": "hackernews:apify",
  "id": "hackernews:49640012",
  "url": "https://news.ycombinator.com/item?id=49640012",
  "authorHandle": "pixel_popping",
  "authorName": null,
  "authorUrl": "https://news.ycombinator.com/user?id=pixel_popping",
  "type": "comment",
  "title": null,
  "text": "Just out of curiosity, may I know why you pay API price at work versus using dozens of subscriptions that you Apify?",
  "language": null,
  "postedAt": "2026-09-10T13:09:14.000Z",
  "likes": 3,
  "reposts": null,
  "replies": null,
  "comments": null,
  "views": null,
  "parentTitle": "DeepSeek v4.1 Flash",
  "parentUrl": "https://news.ycombinator.com/item?id=49639090",
  "instance": null,
  "observedAt": "2026-09-10T14:00:00.000Z"
}

type is story or comment on Hacker News, post, reply or boost on Mastodon, post, reply or repost on Bluesky, and video on YouTube. likes carries points on Hacker News, favourites on Mastodon, likes on Bluesky and the star-rating count on YouTube; views is filled for YouTube. HTML is stripped from text and long text is cut at 2,000 characters.

Watch rows (kind: "watch", free), one per watch per run, with status (ok, baseline on the first check, error, or invalid), how many new posts were found, filtered, delivered, and held for the next run. One summary row (kind: "summary", free) totals everything.

Input

Field	What it does
What to watch	One per line. hn:apify (Hacker News stories and comments containing the phrase). mastodon:#opensource or mastodon:#opensource@fosstodon.org (hashtag on an instance; default mastodon.social). mastodon:@thunderbird@mastodon.online (account). bluesky:@bsky.app (account). youtube:UC... or a channel URL, or youtube:playlist:PL....
Keywords	Optional filter for hashtag, account and channel watches: deliver only posts whose text or title contains any of the words. Hacker News watches carry their own keyword.
Include replies and boosts	Off by default.
First-run look-back (hours)	Default 24. Later runs deliver everything since the previous check.
Snapshot name	Which memory to use; a key-value store named public-mention-monitor-<name>, one record per watch.
Max mentions per run	Default 1,000. Watches whose posts did not fit are re-checked from the same point next run, so nothing is skipped.

Examples:

{ "watches": ["hn:apify", "hn:\"web scraping\"", "mastodon:#webscraping", "bluesky:@apify.com"] }

Everything said about a company and its topic on the open social web, hourly or daily.

{ "watches": ["mastodon:@eff@mastodon.social", "youtube:UC_x5XG1OV2P6uZZ5FSM9Ttw", "bluesky:@nytimes.com"], "keywords": ["privacy", "encryption"] }

Three accounts, only the posts and videos about two topics.

Pricing

Event	Free	Bronze	Silver	Gold and above
Mention	$0.002	$0.0018	$0.0015	$0.0012

A brand keyword on Hacker News produces a few posts a day; a busy Mastodon hashtag a few hundred; an active account a handful. Ten watches typically deliver 50 to 300 mentions a day, $0.10 to $0.60. Watch rows, the summary row, and runs with nothing new are free. Set a maximum total charge on the run to cap spend; the Actor stops cleanly when it is reached, never delivers rows it could not bill, and does not advance a watch until its posts have been delivered.

Use cases

• Brand and product monitoring: mentions of your name, your competitors, or your category as they appear, without a $79-a-month listening tool.
• Developer relations: every Hacker News thread that mentions your tool, with the comment text, ready for a reply.
• Journalists and analysts: follow accounts and hashtags across instances without logging in anywhere.
• Creators: new videos from the channels you track, with view counts, into a sheet.
• AI agents: ask "what was said about X on Hacker News today" through the Apify MCP server and get the rows.

Data source and limits

• Hacker News: the public Algolia search API (stories and comments by date, phrase match confirmed in the text). Mastodon: each instance's public API (hashtag timelines and public account statuses; the Actor stays under the instances' default limit of 300 requests per five minutes). Bluesky: the public AppView (account feeds; Bluesky's post search is not open to unauthenticated clients, so keyword search is not offered there). YouTube: the channel and playlist feeds YouTube publishes (the 15 most recent videos).
• Reddit, X, LinkedIn, Instagram, TikTok, Threads and Facebook are not included: their terms or access controls do not allow this kind of automated reading without an account.
• Only public posts are read. Rows carry the author's public handle and display name as the platform shows them; no profile data, follower lists or private content is collected, and nothing is combined across sources.
• The cadence you schedule is the resolution you get; hourly is common for keywords, daily for accounts.
• At the end of each run the Actor reports run counts (rows delivered, events charged, duration, status) to its maintainer's dashboard. It never sends your input, your results, or anything about your account.

About

Built and maintained by Upward Enterprises · AI & API Services (Iowa, USA). Public-data tools for people and AI agents, with pay-per-record pricing and no keys to manage.

Changelog

• 0.1 (2026-09-10): first release.