Glossary of Terms

A

Allocation

A defined time block when a resource is available to work. Two types exist:

• Weekly Allocation – Recurring weekly schedule (e.g., Mondays 9am-5pm)
• Single Allocation – One-time availability block (e.g., working Saturday this week only)

See Weekly Allocations, Single Allocations.

API Key

Authentication credential used alongside dashboard tokens to access the API. Required for dashboard-based authentication but not for OAuth2 client credentials flow.

See Authentication.

Appointment

A confirmed booking connecting a customer to a service, time slot, and one or more resources. Appointments have statuses (IN, BK, RS, RE, CN) and trigger notifications/webhooks.

See Appointments Guide.

Availability

Time slots when services can be booked. Calculated based on:

• Service duration and padding
• Resource schedules and existing appointments
• Location operating hours
• Booking limits and restrictions

See Availability Guide.

B

BALANCED

Round robin mode that assigns appointments to the resource with the fewest existing bookings in the search window. Distributes workload evenly.

See Round Robin Booking.

Booking Interval

How often time slots are offered for a service. If set to 60 minutes, slots appear hourly regardless of service duration.

See Services Overview.

Booking Limit

Restriction on how many appointments a customer can have. Can be total active, daily count, daily duration, lifetime, or per-resource.

See Booking Limits.

bookingsPerSlot

Maximum number of customers who can book the same time slot. Used for group classes, shared resources, or equipment pools.

See Max Capacity.

C

Calendar Sync

Integration with external calendars (Google Calendar, Outlook) to:

• Push OnSched appointments to external calendar
• Pull external events to block OnSched availability
• Maintain two-way synchronization

See External Calendar Sync.

Cascade

How settings inherit down the hierarchy: Company → Location → Resource. Lower levels can override higher levels.

See Settings Overview.

Client Credentials

OAuth2 authentication flow where client ID and secret are exchanged for an access token. Recommended for server-to-server API integrations.

See Authentication.

Company

Top-level tenant in OnSched. Represents your organization and owns all locations, services, resources, appointments, and customers.

See Companies Overview, Architecture.

Custom Fields

Key-value pairs that extend standard data models with additional information. Available on appointments, customers, services, resources, and locations.

See Appointment Custom Fields, Customer Custom Fields.

Customer

Person who books appointments. Stored with contact information, preferences, appointment history, and custom fields.

See Customers Overview.

D

Duration

Length of a service or appointment in minutes. Core property that determines how long appointments last and affects availability calculations.

See Services Overview.

Duration Selection

Feature allowing customers to choose appointment length within a range (e.g., 30, 60, or 90 minutes) using overrideDuration parameter.

See Services Overview.

E

E.164 Format

International phone number format required for SMS notifications. Includes country code and no formatting characters (e.g., +15550123).

See Customer SMS.

External Calendar

Google Calendar or Outlook calendar connected to a resource for two-way sync. External events block OnSched availability automatically.

See External Calendar Sync.

H

Hold

Temporary appointment reservation with status IN. Holds expire automatically if not confirmed within the expiration window (configurable per location).

See Appointments Guide.

HSTORE

PostgreSQL data type used for Custom Fields. Stores key-value pairs efficiently while allowing queries and indexing.

I

Interval

Parameter controlling how often candidate appointment start times are generated. Separate from service duration—affects slot stepping, not appointment length.

See Availability Guide.

L

Location

Physical or virtual place where services are provided. Locations have:

• Operating hours
• Resources assigned to them
• Optional timezone override
• Webhooks and notification settings

See Architecture.

M

Max Capacity

See bookingsPerSlot.

N

Notification Type

Preference for how notifications are sent:

• EMAIL – Email only
• SMS – Text message only
• ALL – Both email and SMS
• NONE – No notifications

Can be set at company, location, resource, and customer levels.

See Customer SMS.

O

OAuth2

Industry-standard authentication protocol. OnSched supports client credentials flow for server-to-server API access.

See Authentication.

Operating Hours

Times when a location is open for bookings. Defined via weekly unavailability blocks (specify when CLOSED; everything else is open).

See Weekly Allocations.

Out of Office (OOF)

Unavailability block marking a resource as unavailable during specific times (vacation, sick leave, training). Prevents booking appointments during these periods.

overrideDuration

Parameter allowing customer to select appointment duration different from service default (when durationSelect: true on service).

See Availability Guide.

P

Padding

Buffer time added after an appointment. Creates gap between bookings for cleanup, transitions, or rest. Invisible to customers but blocks resource availability.

See Services Overview.

R

RANDOM

Round robin mode that picks any available resource randomly with equal probability. Default assignment strategy.

See Round Robin Booking.

Resource

Person, equipment, or space that delivers services. Examples:

• Staff members (stylists, consultants, instructors)
• Equipment (treadmills, kayaks, projectors)
• Spaces (exam rooms, conference rooms, studios)

See Resources Overview.

Round Robin

Strategy for automatically assigning resources to appointments when multiple resources can fulfill a service. Modes: RANDOM, BALANCED, NONE.

See Round Robin Booking.

S

Scope

Determines whether a service is company-wide (COMPANY) or location-specific (LOCATION). Company-scoped services are available at all locations (where resources exist).

See Service Scoping.

Service

Bookable offering (consultation, haircut, class, equipment rental). Services define duration, padding, pricing, limits, and which resources can deliver them.

See Services Overview.

Single Allocation

One-time availability block for a resource. Used for irregular schedules, extra shifts, or temporary availability.

See Single Allocations.

Slot

A bookable time window shown in availability results. Represents a potential appointment start time that respects all scheduling rules.

SMS

Text message notifications sent to customers' mobile phones. Requires phone number in E.164 format and Twilio configuration.

See Customer SMS.

Soft Delete

Deletion strategy where records are marked as deleted (deletedAt timestamp) but not removed from database. Allows restoration and preserves historical data.

Status

Appointment lifecycle state:

• IN – Initial hold (auto-expires if not confirmed)
• BK – Booked appointment
• RS – Reserved hold (longer expiration)
• RE – Rescheduled (placeholder for moved appointment)
• CN – Cancelled

See Appointments Guide.

Swagger

Interactive API documentation auto-generated from OpenAPI specification. Available at API root URL for testing endpoints and viewing schemas.

See Swagger Documentation.

T

Timezone

IANA timezone identifier (e.g., America/New_York, Europe/London, Asia/Tokyo). Used to interpret date-only inputs and display times in local context.

Can be set at company, location, and resource levels.

Token

Access token obtained via OAuth2 client credentials flow. Short-lived (1 hour) bearer token used to authenticate API requests.

See Authentication.

Twilio

SMS gateway service OnSched uses to send text message notifications. Handles message delivery to customer phone numbers.

See Customer SMS.

U

Unavailability

Time block that prevents booking appointments. Types include:

• APT – Appointment (customer booking)
• HLD – Hold (temporary reservation)
• PAD – Padding (buffer time)
• OOF – Out of Office (vacation, sick)
• EXT – External event (from calendar sync)

See Unavailability Management (if exists).

UUID

Universally Unique Identifier. 128-bit value used as primary key for all OnSched resources (format: a1b2c3d4-e5f6-7890-abcd-ef1234567890).

W

Webhook

HTTP callback triggered by appointment events. Sends JSON payload to your server when events occur (new appointment, cancellation, rescheduling, etc.).

See Webhooks Guide.

Weekly Allocation

Recurring weekly schedule defining when a resource works at a location. Example: Resource works Mondays 9am-5pm at Location A, Tuesdays 9am-5pm at Location B.

See Weekly Allocations.

Common Acronyms

• API – Application Programming Interface
• CRM – Customer Relationship Management
• GDPR – General Data Protection Regulation (EU privacy law)
• IANA – Internet Assigned Numbers Authority (manages timezone database)
• ISO 8601 – International standard for date/time formatting
• JWT – JSON Web Token (used for dashboard authentication)
• OAuth2 – Open Authorization 2.0 (authentication protocol)
• REST – Representational State Transfer (API architecture style)
• SMS – Short Message Service (text messaging)
• TCPA – Telephone Consumer Protection Act (US SMS regulations)
• URL – Uniform Resource Locator
• UTC – Coordinated Universal Time (timezone reference)
• UUID – Universally Unique Identifier

Status Codes

Common HTTP status codes returned by the API:

• 200 OK – Request succeeded
• 201 Created – Resource created successfully
• 400 Bad Request – Malformed request or missing parameters
• 401 Unauthorized – Invalid or missing authentication
• 403 Forbidden – Authenticated but lacking permission
• 404 Not Found – Resource doesn't exist
• 422 Unprocessable Entity – Request fails business logic validation
• 500 Internal Server Error – Unexpected server error

See Error Codes.

Related Documentation

• Getting Started – Introduction to OnSched
• Architecture – Understanding the hierarchy
• Authentication – API access and credentials
• Swagger Documentation – Interactive API reference

This glossary provides quick definitions of OnSched terms. For detailed explanations and usage examples, see the linked documentation guides.