Book modality session

POST

/v1/actions/hospitality.action.book_modality_session/apply

curl --request POST \
  --url https://api.aerandil.com/v1/actions/hospitality.action.book_modality_session/apply \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{ "branch": "2489E9AD-2EE2-8E00-8EC9-32D5F69181C0", "params": { "external_record_reference_id": "2489E9AD-2EE2-8E00-8EC9-32D5F69181C0", "modality_id": "2489E9AD-2EE2-8E00-8EC9-32D5F69181C0", "scheduled_at": "2026-04-15T12:00:00Z", "venue_id": "2489E9AD-2EE2-8E00-8EC9-32D5F69181C0" }, "return_modified": false, "target": { "id": "2489E9AD-2EE2-8E00-8EC9-32D5F69181C0", "object_type": "hospitality.membership" } }'

• Production API

Book a wellness-modality session for the target membership. For clinical modalities (requires_medical_licensing = true), the matching external_record_reference_id parameter is mandatory at action-time — the handler rejects the booking otherwise. Non-clinical modalities (cold/heat/contrast therapy, resistance training, recovery, mindfulness, sleep work) book without the clinical-seam parameter.

Effects: create hospitality.venue_visit; link hospitality.link.venue_visit_at_venue; link hospitality.link.venue_visit_for_person; link hospitality.link.venue_visit_for_modality; link hospitality.link.venue_visit_references_external_record.

Authorizations

• aerandil_oauth
  actions:apply
• aerandil_oauth
  actions:hospitality.action.book_modality_session:apply

Request Body^required

Media typeapplication/json

object

branch

Apply against an open branch’s overlay view instead of the canonical (main) plane. The action’s writes land in the branch’s copy-on-first-write overlay, its events in the branch’s own stream, and the invocation is journaled for merge-by-replay. Branch writes are action-only, so this is the write-side entry point to a branch (POST /v1/branches forks one).

string format: uuid

params

required

object

external_record_reference_id

Clinical-record reference (mandatory when modality requires_medical_licensing)

string format: uuid

modality_id

required

Modality being booked

string format: uuid

scheduled_at

required

Session start time

string format: date-time

venue_id

required

Venue where the session is booked

string format: uuid

return_modified

When true, the response carries modified_objects and modified_links projections — the engine reads the event log inside the same transaction so the projection observes the handler’s own writes.

boolean

target

required

object

id

required

string format: uuid

object_type

required

Allowed value: hospitality.membership

Responses

200

Action applied. modified_objects and modified_links populated when return_modified: true was supplied.

Media typeapplication/json

ApplyActionResponse

Envelope returned by the Aerandil action engine. correlation_id ties every event emitted by this invocation; modified_objects and modified_links project the events the handler emitted (per the action’s declared effects); warnings carries any non-blocking soft-validator observations.

object

correlation_id

required

Per-invocation correlation id; matches events.correlation_id for every event this action appended.

string format: uuid

modified_links

required

Links established or removed by this invocation. Empty when the caller did not request return_modified.

Array<object>

object

from_id

required

string format: uuid

from_type

required

string

kind

required

Allowed values: linked

link_type

required

Allowed values: hospitality.link.venue_visit_at_venue hospitality.link.venue_visit_for_person hospitality.link.venue_visit_for_modality hospitality.link.venue_visit_references_external_record

to_id

required

string format: uuid

to_type

required

string

modified_objects

required

Objects created, modified, or soft-deleted by this invocation. Empty when the caller did not request return_modified.

Array<object>

object

id

required

string format: uuid

kind

required

Allowed values: created

object_type

required

Allowed values: hospitality.venue_visit

warnings

Non-blocking soft-validator observations emitted during this invocation (e.g. comp-authority over-limit, recipe pour-cost over sell-price). Absent when no warnings were emitted.

Array<object>

object

message

required

Human-readable summary, suitable for logging or operator-UI surfacing.

string

object_type

required

Object type the warning was raised against.

string

property

Property the warning anchors to, when a single field is the locus. Absent for multi-field rules.

string

rule

required

Stable kebab-case rule identifier (e.g. comp-authority-over-limit).

string

Example

{
  "modified_links": [
    {
      "kind": "linked",
      "link_type": "hospitality.link.venue_visit_at_venue"
    }
  ],
  "modified_objects": [
    {
      "kind": "created",
      "object_type": "hospitality.venue_visit"
    }
  ]
}

409

Conflict — concurrent modification or unique constraint violation.

422

Validation error — parameter validation or business-rule violation.