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Messaging capability

Check which messaging service is currently available for an E.164 phone number. This is a read-only lookup and does not require an agent identity or an existing conversation.

Check messaging capability GET

GET /check-messaging-capability

Query parameters

ParameterTypeRequiredDescription
numberstringYesRecipient phone number in E.164 format

URL-encode the leading + as %2B when you place the number in the query string:

bashbash

Use an admin API key or claimed agent key. Unclaimed (mid-signup) agent keys are rejected.

Response (200)

The response body is a JSON string—not an object—and is always one of iMessage, SMS, or RCS:

JSONJSON

Check capability close to the time you intend to message the recipient because service availability can change.

Error responses

StatusDescription
401Authentication is missing or invalid
403The credential is valid but is not permitted to perform capability lookups
422number is missing or is not a valid phone number
502Capability information is temporarily unavailable

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Messaging capability