Create a campaign

Creates a new DRAFT campaign — the same starting point as clicking “New Campaign” in the app. Combined with add-leads and start, this is what makes a full create → add leads → start integration possible entirely through the API.

Stablescope: write API KeyLearn about API scopes →

Trailing slash required

Call this as /v1/campaigns/, not /v1/campaigns — the bare path without a trailing slash 404s before it reaches Stynar's servers at all, for both GET (list) and POST (create). Every other endpoint on this API works with or without a trailing slash; this exact path is the one exception.

Unknown fields are rejected

The request body is validated strictly — any field not listed below returns 400 VALIDATION_FAILED instead of being silently ignored.

Request

Authorization	Bearer YOUR_API_KEY
Content-Type	application/json

Parameters

Field	Type	Required	Description
name	string	Required	Campaign name, 1–200 characters.
senderIds	string[]	Optional	IDs of connected sending accounts to send from, up to 50.
mail	object	Optional	Static content: { subject, previewText, body, fromName, fromEmail, replyTo }. Use this or aiPrompt, not both.
aiPrompt	object	Optional	AI-generated content instead of mail: { prompt, promptId, tone, length }.
aiModel	string	Optional	Which AI model to use when generating from aiPrompt.
abTest	object	Optional	{ enabled, variantB?: { subject, body } } — A/B test a second subject/body variant.
scheduleType	enum	Optional	now \| schedule \| gradual — how sending is paced. Defaults to sending as soon as started.
timezone	string	Optional	IANA zone (e.g. America/New_York) — used by 'schedule' and 'gradual'.
scheduleStartDate	string	Optional	Start date-time for 'schedule' and 'gradual'.
scheduleEndDate	string	Optional	End date-time for 'schedule' and 'gradual'.
gradualSettings	object	Optional	Required when scheduleType is 'gradual': { startingVolume, increment, safetyThreshold, sendOnSpecificDays, selectedWeekdays }.
sendMode	enum	Optional	direct \| draft — 'draft' isn't supported together with scheduleType: 'gradual'.

curl -X POST "https://api.stynar.com/v1/campaigns/" \
  -H "Authorization: Bearer esk_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{"name":"Q3 outbound","mail":{"subject":"Quick question about {{company}}","body":"<p>Hi {{firstName}},</p>..."}}'

With a sender, A/B test, and a gradual schedule

curl -X POST "https://api.stynar.com/v1/campaigns/" \
  -H "Authorization: Bearer esk_your_key_here" \
  -H "Content-Type: application/json" \
  -d '{"name":"Q3 outbound - gradual ramp","senderIds":["sender_abc123"],"mail":{"subject":"Quick question about {{company}}","body":"<p>Hi {{firstName}},</p>..."},"abTest":{"enabled":true,"variantB":{"subject":"{{firstName}}, quick question"}},"scheduleType":"gradual","timezone":"America/New_York","gradualSettings":{"startingVolume":20,"increment":5,"safetyThreshold":"bounce_rate","sendOnSpecificDays":true,"selectedWeekdays":["Monday","Tuesday","Wednesday","Thursday","Friday"]}}'

Response

✓ 201 Created

201 response

{
  "campaign": {
    "campaignId": "cmp_abc123",
    "name": "Q3 outbound",
    "status": "DRAFT",
    "senderIds": [],
    "mail": {
      "subject": "Quick question about {{company}}",
      "body": "<p>Hi {{firstName}},</p>..."
    },
    "createdAt": "2026-08-16T10:02:11Z"
  }
}

Response fields

Errors

Status	Code	Meaning
✕ 401 Unauthorized	UNAUTHORIZED	Missing, malformed, unknown, revoked, or expired key.
✕ 403 Forbidden	API_ACCESS_DISABLED	Your account doesn't currently have API access.
✕ 403 Forbidden	INSUFFICIENT_SCOPE	The key doesn't have the scope this endpoint requires.
✕ 404 Not Found	NOT_FOUND	Unknown route, or a resource that doesn't exist / isn't yours.
✕ 409 Conflict	CONFLICT	The action can't be applied to the resource's current state.
✕ 429 Too Many Requests	RATE_LIMIT_EXCEEDED	Per-minute or per-second limit hit.
✕ 429 Too Many Requests	QUOTA_EXCEEDED	Monthly quota exhausted.
✕ 500 Internal Server Error	INTERNAL_ERROR	Something broke on Stynar's end.

Full error reference →

NextLaunch a campaign