The API your
agents call
before writing
to a calendar.
When sales-bot, cal.ai, recruiting-bot, and your focus-time agent all want the same Tuesday 9 AM — Openavail picks one (by your rules, not last-write-wins) and writes the receipt.
v1 · Public Beta · Early Access
◇ one slot · five agents · one winner · five audit rows
Google Workspace supported today · Microsoft 365 on the roadmap — join the waitlist
One POST.
One decision.
One audit row.
No client SDK required. If your agent speaks HTTP, it speaks Openavail. MCP server lands in v1.5.
▸ REQUEST
curl -X POST https://api.openavail.com/v1/availability \
-H "Authorization: Bearer ak_01HXYZ..." \
-H "Idempotency-Key: lead-12345-attempt-1" \
-d '{
"owner_email": "[email protected]",
"meeting_class": "external_customer_call",
"duration_minutes": 30,
"window": {
"start": "2026-06-04T09:00:00Z",
"end": "2026-06-04T17:00:00Z"
}
}'◂ RESPONSE
{
"hold_id": "hld_8XnPq7r3…",
"expires_at": "2026-06-04T09:05:00Z",
"slots": [
{ "start": "2026-06-04T10:00:00Z", "end": "2026-06-04T10:30:00Z" },
{ "start": "2026-06-04T14:00:00Z", "end": "2026-06-04T14:30:00Z" }
],
"resolved_calendar_type": "work",
"warnings": []
}Three primitives.
That's the whole product.
Ask before you book
Every agent points at one URL — Openavail. Before it writes to Google or Outlook, it asks us: "is this slot really free?" We answer yes, no, or try-this-instead — against rules you set.
Priority, not chaos
When two agents want the same slot in the same millisecond, Openavail picks one — by the rules you wrote, not by whoever was faster to commit. Deterministic. Same inputs always produce the same winner.
How arbitration works →A receipt for every decision
Every accept, reject, preempt, and counter-propose is an audit row. Which agent. Which key. Which rule fired. Queryable forever, exportable as JSONL.
Many agents in.
One decision out.
Your agents stop talking to Google directly. They talk to Openavail. We hold the only real token — and own the only writes to the calendar.
"Planes don't collide because someone, somewhere, is paying attention."
"Which agent
booked over my
CEO 1:1?"
Five-second answer. By agent identity, by API key, by rule fired, by calendar owner. Exportable as JSONL. Indexed forever. The artifact your security team asks for in week one of any procurement review.
DECISION HISTORY · LIVE CONSOLE

One flat price.
No seat math.
See full pricing →- ▸1 calendar · 1 agent
- ▸50 bookings / month
- ▸7-day audit log
- ▸5 calendars · 5 agents
- ▸Simulation + drift detection
- ▸90-day audit log
- ▸10 calendar owners
- ▸Team roles + org classes
- ▸1-year audit log
How is this different from Calendly or Reclaim?
Does Openavail replace Google Calendar?
How do agents authenticate?
Is the arbitration logic AI-powered?
Does it support Microsoft 365?
GOOGLE WORKSPACE SUPPORTED · MICROSOFT 365 ON THE ROADMAP — JOIN THE WAITLIST · PRICING SUBJECT TO CHANGE DURING PUBLIC BETA