Nylas · Schema
Nylas message.send_failed notification object
The `data` object includes `grant_id`, `reason`, and `error` at the same level as `object`.
CalendarCommunicationsContactsEmailMessagingSchedulingA2A
Properties
| Name | Type | Description |
|---|---|---|
| grant_id | string | The grant ID that attempted to send this message. |
| reason | string | Human-readable reason for the send failure. |
| error | object | Detailed error information about the failure. |
| object | object | The scheduled message that failed to send. May be `null` if the message could not be constructed. |
JSON Schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"$id": "https://raw.githubusercontent.com/api-evangelist/nylas/refs/heads/main/json-schema/nylas-message-send-failed.schema.json",
"title": "Nylas message.send_failed notification object",
"description": "The `data` object includes `grant_id`, `reason`, and `error` at the same level as `object`.",
"type": "object",
"properties": {
"grant_id": {
"type": "string",
"description": "The grant ID that attempted to send this message."
},
"reason": {
"type": "string",
"description": "Human-readable reason for the send failure."
},
"error": {
"type": "object",
"description": "Detailed error information about the failure.",
"properties": {
"type": {
"type": "string",
"description": "The Nylas error type (e.g. `api.provider_error`)."
},
"message": {
"type": "string",
"description": "Human-readable error message."
},
"status_code": {
"type": "integer",
"description": "HTTP status code from the provider."
},
"provider_error": {
"type": "object",
"description": "Raw error response from the email provider.",
"additionalProperties": true
}
},
"required": [
"type",
"message"
]
},
"object": {
"type": "object",
"description": "The scheduled message that failed to send. May be `null` if the message could not be constructed.",
"properties": {
"object": {
"type": "string",
"description": "Always `message`.",
"enum": [
"message"
]
},
"grant_id": {
"type": "string",
"description": "The grant ID that attempted to send this message."
},
"id": {
"type": "string",
"description": "The Nylas message ID."
},
"subject": {
"type": "string",
"description": "The message subject line."
},
"body": {
"type": "string",
"description": "The message body."
},
"from": {
"type": "array",
"description": "Sender information.",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"format": "email"
}
}
}
},
"to": {
"type": "array",
"description": "Primary recipients.",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"format": "email"
}
}
}
},
"cc": {
"type": "array",
"description": "CC recipients.",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"format": "email"
}
}
}
},
"bcc": {
"type": "array",
"description": "BCC recipients.",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"format": "email"
}
}
}
},
"reply_to": {
"type": "array",
"description": "Reply-to addresses.",
"items": {
"type": "object",
"properties": {
"name": {
"type": "string"
},
"email": {
"type": "string",
"format": "email"
}
}
}
},
"attachments": {
"type": "array",
"description": "Attachment metadata.",
"items": {
"type": "object",
"properties": {
"id": {
"type": "string",
"description": "Attachment ID."
},
"filename": {
"type": "string",
"description": "Original filename."
},
"content_type": {
"type": "string",
"description": "MIME type."
},
"size": {
"type": "integer",
"description": "Size in bytes."
},
"content": {
"type": "string",
"description": "Base64-encoded attachment content."
}
}
}
},
"schedule_id": {
"type": "string",
"description": "The scheduled send job ID."
},
"send_at": {
"type": "integer",
"description": "Unix timestamp when the message was scheduled to send."
},
"use_draft": {
"type": "boolean",
"description": "Whether the message was sent from a draft."
}
},
"nullable": true
}
},
"required": [
"grant_id",
"reason",
"error",
"object"
],
"x-nylas-trigger": "message.send_failed",
"x-nylas-category": "Messages",
"x-provenance": {
"method": "authored",
"publisher": "Nylas",
"source": "https://developer.nylas.com/docs/reference/notifications/messages/message-send_failed/",
"derived_from": "nylas/developer.nylas.com@a7995fb6:src/_component-data/notification-schemas.json",
"generated": "2026-09-28"
},
"x-nylas-upstream-issue": "The published example for this trigger does not validate against its published schema ('message' is not of type 'object'; 'reason' is a required property; 'error' is a required property), so it is omitted here. Reported to the Nylas docs team."
}
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