Validate SMS (dry run)

Designing

POST

/messages/sms/validate

Dry run. Resolves the recipient, evaluates suppression and consent, verifies the sender, resolves the template and diffs the supplied variables against the ones the template references. Nothing is sent and no message record is created.

This is a resolution check, not a render — commons resolves, the mailing infrastructure renders. variables.missing is the value here: template-variable typos are the most common transactional integration bug.

Useful in both modes. With type: marketing it answers "would this actually go out?" before you send. With type: transactional it reports consent.required=false and shows you exactly which check you are exempting yourself from.

Request

Header Params

Body Params application/jsonRequired

Examples

Responses

🟢200OK

application/json

Resolution report plus a segment/encoding estimate. Nothing was sent.

Bodyapplication/json

🟠400Bad Request

🟠401Unauthorized

🟠403Forbidden

🟠422Unprocessable Entity

🟠429Too Many Requests

Request Example

Shell

JavaScript

Java

Swift

curl --location '/messages/sms/validate' \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '{
    "type": "transactional",
    "basis": "contract_performance",
    "to": {
        "contactId": "string",
        "clientContactId": "string",
        "phoneNumber": "string"
    },
    "from": "string",
    "templateId": 0,
    "content": "string",
    "language": "string",
    "variables": {},
    "tags": [
        "string"
    ],
    "metadata": {},
    "sendAt": "string",
    "createContact": true,
    "retainBody": true,
    "event": "string",
    "permId": "string"
}'

Response Example

200 - Example 1

{
    "channel": "email",
    "type": "transactional",
    "recipient": {
        "contactId": "string",
        "resolved": "string",
        "deliverable": true
    },
    "suppression": {
        "suppressed": true,
        "reason": "string"
    },
    "consent": {
        "required": true,
        "granted": true,
        "lists": [
            "string"
        ]
    },
    "sender": {
        "from": "string",
        "verified": true,
        "domainId": 0
    },
    "template": {
        "templateId": 0,
        "language": "string",
        "resolved": true
    },
    "variables": {
        "missing": [
            "string"
        ],
        "unused": [
            "string"
        ]
    },
    "sms": {
        "length": 0,
        "encoding": "GSM7",
        "segments": 0,
        "estimate": true
    }
}

Modified at 2026-09-07 17:57:53

Send SMS (batch)

List messages