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Create Participant Session

Authorizations

Authorization
string
header
required

Named syn_ API key or migration-only legacy key.

Headers

Idempotency-Key
string
required
Required string length: 1 - 255

Path Parameters

organization_id
string<uuid>
required
app_id
string<uuid>
required
environment_id
string<uuid>
required

Body

application/json
program_id
string<uuid>
required
subject_id
string<uuid>
required
evidence
Evidence · object
expires_in_seconds
integer
default:3600

Seconds until the participant link stops working: one hour by default, up to ten years. Resending the same launch (this field may differ) while its session is still open returns that session and extends its expiry to at least this long from now; it never shortens it.

Required range: 300 <= x <= 315360000
locale
string
default:en
Required string length: 2 - 35
Pattern: ^[a-z]{2,3}(?:-[A-Z]{2})?$
signals
Signals · object
subject_context
Subject Context · object

Response

Successful Response

branding
ExperienceBranding · object
required

Participant-safe branding pinned by an immutable experience version.

evaluation_id
string<uuid>
required
expires_at
string<date-time>
required
participant_token
string
required
renderer_mode
enum<string>
required
Available options:
hosted,
embedded,
hosted_or_embedded
session_id
string<uuid>
required
hosted_url
string | null