Skip to main content
Horizon’s Slack app is the fastest way to use Horizon — no code, no API key to manage yourself. Ask questions in plain English in a channel, a DM, or with a slash command, and the same enrichment engine that powers the REST API and MCP server does the work.
Building your own agent or workflow instead? See the Quickstart for the REST API, or MCP Install to wire Horizon into Claude, Cursor, or another MCP client.

​
1. Install the app

Click Add to Slack (your Horizon contact or the product page has the link) and approve the OAuth consent screen for your workspace. Horizon requests the bot scopes it needs to reply in channels/DMs, react with a status emoji, read thread history it’s already participating in so follow-ups work without re-mentioning it, and upload CSV exports for large result lists — nothing beyond what those features require.

​
2. Complete signup

Right after install, Horizon DMs you:
👋 Thanks for installing Horizon! Before I can answer questions, complete a quick, free signup (verifies a card on file, no charge): [link]
That link opens a Stripe Checkout page in setup mode — it verifies a card on file to deter abuse of the free trial, but charges nothing. Completing it grants your workspace 200 free credits and a confirmation DM arrives:
🎉 You’re all set! Horizon granted your workspace 200 free credits (200 available). Just @mention me or use /usehorizon with a question — e.g. “find John Doe’s email at acme.com”. Need more later? Buy a pack: [link]
No one in the workspace can ask Horizon a real question until this step is done — an @mention or /usehorizon before signup just re-sends the same signup link instead of running anything (so nothing is ever billed before you’ve completed it).

​
3. Ask your first question

Three ways to talk to Horizon:
  • @mention it in any channel it’s in: @Horizon find the CEO of Acme Corp
  • DM it directly, no @mention needed
  • Slash command: /usehorizon find the CEO of Acme Corp
Horizon replies in a thread under your question (or under the message it echoes back, for a slash command), with a short progress update if the request takes a few tool calls, and a final answer that ends with what it spent — e.g. _Spent 27 credits · 173 remaining_.

​
Buying more credits

When your free trial runs low, ask Horizon (it’ll tell you when you’re out) or DM it any time — every confirmation message includes a direct top-up link for the next pack. See Credits & Pricing for the full pack list; Slack, REST, and MCP all draw from the same balance, so a pack bought from Slack works everywhere else too.

​
What’s next

See Using Horizon in Slack for the full rundown — compound requests, list/batch processing, the spend-confirmation card, and the free-tier daily limit.