> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tikk.chat/llms.txt
> Use this file to discover all available pages before exploring further.

# How Tikk finds open time slots

> Tikk layers your weekly schedule, date overrides, buffer times and synced calendars to compute open slots.

Tikk builds your available slots from four layers: your weekly schedule, date overrides, buffer times and every connected calendar. A slot only shows up when it clears all four.

## What determines availability

Tikk applies these layers in order:

<Steps>
  <Step title="Weekly schedule">
    Your weekly schedule is the base. Set the hours you're open for each day of the week (say, Mon-Fri 09:00-17:00). Slots outside those windows never show.
  </Step>

  <Step title="Date overrides">
    Adjust or block availability on specific dates. Use these for holidays, vacation or one-off changes to your hours.
  </Step>

  <Step title="Synced calendars">
    Tikk checks every connected calendar. If any calendar has a busy event overlapping a slot, the slot is hidden. No double bookings.
  </Step>

  <Step title="Buffer times">
    Buffers add a gap before or after each booking. With a 15-minute buffer after, a meeting ending at 10:00 pushes the next slot to 10:15.
  </Step>

  <Step title="Service-specific settings">
    Each service can override the base window and set its own lead time (like "at least 24 hours notice"). These narrow the pool further.
  </Step>
</Steps>

## How slots are generated

Tikk splits your open windows into slots of the service's duration (default 30 minutes). A slot only makes the response if it passes every layer. One conflict, one drop.

<Info>
  Slots are generated in real time when you hit the availability endpoint. Results always reflect your latest calendar state.
</Info>

## Slot fields

Each slot returns:

| Field             | Type          | Description                                                                      |
| ----------------- | ------------- | -------------------------------------------------------------------------------- |
| `start`           | UTC date-time | Slot start as a UTC ISO 8601 timestamp (e.g. `2025-09-15T09:00:00Z`).            |
| `end`             | UTC date-time | Slot end as a UTC ISO 8601 timestamp.                                            |
| `label`           | string        | Start time formatted in the **host's timezone**, ready to display.               |
| `spots_remaining` | integer       | *(Group services only)* Seats left in the slot. Omitted for one-to-one services. |

`start` and `end` are always UTC so you can do reliable time math. Use `label` when you want a ready-to-show string in the host's local time.

## Timezone handling

Your weekly schedule and date overrides live in **your timezone**, set in account settings. Each returned slot includes a `label` in your timezone. Bookers see times auto-converted to their local timezone.

<Warning>
  If you change your account timezone, review your schedule and any active overrides. Stored hours don't shift with the timezone change.
</Warning>

## General vs service-scoped availability

You can query in two modes:

<Tabs>
  <Tab title="General availability">
    Without a `service` parameter you get your overall open windows from the base schedule. Useful for a broad calendar view or checking whether you're free on a given day.

    ```http theme={null}
    GET https://app.tikk.chat/api/v1/availability
    ```
  </Tab>

  <Tab title="Service-scoped availability">
    Scoping to a service applies its duration, lead time and availability settings on top of your base schedule. This is what the booking page uses to show real bookable slots.

    ```http theme={null}
    GET https://app.tikk.chat/api/v1/availability?service=discovery-call
    ```
  </Tab>
</Tabs>

Use service-scoped availability for booking flows so the slots you show match what someone can actually reserve.

<Note>
  Full request and response shape lives in the [List Availability](/api-reference/availability/list-availability) reference.
</Note>