Validate a payload

Check a send request for SMS, WhatsApp or RCS against the API before you send it.

Paste a request body below to see what the API would reject, before you spend a send on it. The check runs in your browser: nothing is sent, and your payload and API key never leave the page.

What it checks

API	Checks
SMS, India	Required fields, type (SI, OTP or SE, case-sensitive), recipient format, DLT IDs, Unicode, custom references, URL shortening
SMS, international	key, the 2,500-message limit, numbers with country codes, Unicode
WhatsApp template	Envelope fields, business number, template name and language, components, buttons, carousels
WhatsApp session message	Message type and its required fields, interactive buttons, lists and carousels
RCS	messageType, recipients, ttl format, customParams as a JSON string, rich card and carousel limits
Fallback	fallback_id, the fallback flag and wait_time, how wait_time interacts with an RCS ttl, and the SMS, WhatsApp or RCS fallback message, on any primary channel

Every finding names the field, says what is wrong, and where the API rejects it, gives the response you would get back — for example invalid type with status 700.

It also catches two mistakes that look valid:

• Long IDs sent as numbers. A 19-digit DLT template ID written without quotes is rounded by any JavaScript that parses the JSON on its way to OneXtel, such as a browser, a Node service or a no-code tool. Quote every ID.
• Numbers that cannot receive. /send_sms accepts and bills a recipient that is not a real mobile number. The validator flags anything outside the 6–9 mobile series.

What it cannot check

Some rejections depend on your account, so only a real send reveals them:

• whether the template is approved, and approved for this sender
• whether the message body matches the registered DLT template word for word
• whether the sender ID, entity ID and template belong to your API key
• your balance and sending limits

For what each delivery failure means, see the error codes for India SMS, WhatsApp and RCS.

Reading the results

Level	Means
Error	The API rejects this, or the message cannot be delivered as written
Warning	The API accepts it, but the message may not arrive as intended, or may cost credit for nothing
Note	Correct, with a consequence worth knowing before you send