openapi: 3.2.0
info:
  title: Nylas Transactional send API
  version: v3
  summary: The complete Nylas v3 API — Email, Calendar, Contacts, Notetaker, Scheduling, Administration, and Migration.
  description: The Nylas API is designed using the REST ideology to provide simple and predictable URIs to access and modify objects.
  contact:
    url: https://www.nylas.com/
  x-provenance:
    method: harvested
    first_party: true
    publisher: Nylas
    source: https://developer.nylas.com/_spec-files/nylas-api.yaml
    harvested: '2026-08-21'
    sha256: 7ff001d571e163b1ffe22178741b59f813d8208ec878157a839a33dc2c13fd35
    bytes: 1666223
    note: 'Published by Nylas as the unified contract for the Nylas v3 API and stored verbatim; API Evangelist added only this provenance block. Submitted by the provider in api-evangelist/nylas#1 and verified against the live URL before harvest: OpenAPI 3.1.0, 118 paths, 208 operations, 174 component schemas, 100% of operations carrying summary, description, tag and a unique operationId, x-code-samples on 208 of 208. This document REPLACES a 22-operation scaffold API Evangelist derived from reading the documentation, now quarantined under openapi/_scaffold/.'
  x-evidence:
  - url: https://developer.nylas.com/_spec-files/nylas-api.yaml
    what: the published unified contract, harvested verbatim 2026-08-21 (200, text/yaml, 1,666,223 bytes)
  - url: https://developer.nylas.com/.well-known/api-catalog
    what: RFC 9727 linkset advertising that URL as service-desc for api.us.nylas.com and api.eu.nylas.com (200, application/linkset+json)
servers:
- url: https://api.us.nylas.com
  description: U.S.
- url: https://api.eu.nylas.com
  description: E.U.
security:
- ACCESS_TOKEN: []
- NYLAS_API_KEY: []
tags:
- name: Transactional send
  description: Nylas' Transactional Send endpoint lets you send messages directly from an email domain that you've verified with Nylas. You can use this to send password reset emails, account verifications, or system notifications.
paths:
  /v3/domains/{domain_name}/messages/send:
    parameters:
    - name: domain_name
      in: path
      schema:
        type: string
      required: true
      description: 'The verified sender domain Nylas will send the message from. This path parameter is separate from

        `tracking_options.domain_name`, which selects the hostname for link click and message open

        tracking.'
      example: sender.example.com
    - in: header
      name: Idempotency-Key
      schema:
        type: string
        maxLength: 256
      required: false
      description: 'A unique, client-generated key (max 256 characters) that lets you safely retry this send request

        without sending duplicate emails. Nylas caches the response (success or error) for 1 hour, scoped

        per Nylas application (not per domain -- a key collides across all verified domains under the same

        application). A retry with the same key and payload returns the cached response with the

        `Idempotent-Response: true` header set. See

        [Idempotent send requests](/docs/v3/email/idempotent-send/) for the full retry behavior and

        error responses.'
      example: f47ac10b-58cc-4372-a567-0e02b2c3d479
    post:
      summary: Send a transactional email
      tags:
      - Transactional send
      operationId: send-transactional-email
      x-beta: true
      description: 'Sends a message from the specified domain. You can track deliverability (delivered, bounced, complaint, rejected) using Nylas'' notifications.


        The route''s `domain_name` value is the verified sender domain. To use a different custom hostname

        for link click or message open tracking, provide `tracking_options.domain_name` in the request

        body. For example, you can send from `sender.example.com` and track through

        `tracking.example.com`. Nylas validates scheduled custom tracking hostnames when you create the

        schedule and revalidates them immediately before delivery. If an explicit hostname is no longer

        eligible, the send fails without falling back to a Nylas hostname.


        💡 Emails landing in spam? Consider warming up your email domain to improve deliverability.'
      x-scopes: []
      security:
      - NYLAS_API_KEY: []
      - ACCESS_TOKEN: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - from
              - to
              properties:
                attachments:
                  type: array
                  description: An array of files to be sent with the message.
                  items:
                    type: object
                    properties:
                      content:
                        type: string
                        description: 'The Base64-encoded file content. See

                          [Working with email attachments](/docs/v3/email/attachments/#attachment-schemas-and-size-limits)

                          for more information.'
                        example: YXR0YWNoDQoNCi0tLS0tLS0tLS0gRm9yd2FyZGVkIG1lc3NhZ2UgL=
                      content_disposition:
                        type: string
                        description: '(Not supported for Microsoft and EWS) The content disposition of the file. Usually,

                          this is `inline` or `attachment`, followed by the file name.'
                        example: attachment; filename="nylas_logo.png"
                      content_id:
                        type: string
                        description: '(Inline attachments only) The alphanumeric `cid` from the `<img>` tag in the HTML

                          message body. To avoid unexpected behavior in threads, make sure to use unique CIDs

                          across messages of a thread.'
                        example: ce9b9547-9eeb-43b2-ac4e-58768bdf04e4
                      content_type:
                        type: string
                        description: 'The

                          [MIME type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types)

                          of the file. This is used by the email client to determine how to display the

                          attachment.'
                        minLength: 1
                        example: image/png
                      filename:
                        type: string
                        description: The file name.
                        minLength: 1
                        example: nylas_logo.png
                bcc:
                  type: array
                  description: A list of people to be BCC'd on the message.
                  items:
                    type: object
                    properties:
                      email:
                        type: string
                        description: The recipient's email address.
                        example: leyah@example.com
                      name:
                        type: string
                        description: The recipient's name.
                        example: Leyah Miller
                body:
                  type: string
                  description: The HTML-formatted body of the message.
                  example: Looking forward to seeing you!
                cc:
                  type: array
                  description: A list of people to be CC'd on the message.
                  items:
                    type: object
                    properties:
                      email:
                        type: string
                        description: The recipient's email address.
                        example: leyah@example.com
                      name:
                        type: string
                        description: The recipient's name.
                        example: Leyah Miller
                custom_headers:
                  type: array
                  description: An array of custom headers to add to the message.
                  items:
                    type: object
                    properties:
                      name:
                        type: string
                        description: The header name.
                        example: Email-Campaign
                      value:
                        type: string
                        description: The header value.
                        example: meetings
                from:
                  type: object
                  description: Information about the person sending the message.
                  properties:
                    email:
                      type: string
                      description: 'The sender''s email address. Must belong to an email domain that''s been verified

                        with Nylas.'
                      example: nyla@example.com
                    name:
                      type: string
                      description: The sender's name.
                      example: Nyla
                is_plaintext:
                  type: boolean
                  description: 'When `true`, Nylas sends the message body as plain text and the MIME data doesn''t

                    include an HTML version of the message. When `false`, Nylas sends the message body as

                    HTML.'
                  default: false
                  example: true
                metadata:
                  $ref: '#/components/schemas/metadata'
                reply_to:
                  type: array
                  description: A list of people who should receive replies to the message by default.
                  items:
                    type: object
                    properties:
                      name:
                        type: string
                        description: The name of the person who should receive replies to the message.
                        example: Leyah Miller
                      email:
                        type: string
                        description: The email address of the person who should receive replies to the message.
                        example: leyah@example.com
                reply_to_message_id:
                  type: string
                  description: 'The ID of the message you are replying to. If you are using a message that was sent using Nylas''

                    Transactional Send, you may use the ID that was returned in the Nylas response. For all other

                    messages, this is the [RFC822](https://datatracker.ietf.org/doc/html/rfc822#section-4.6.1)

                    `Message-ID` header of the message you''re replying to.'
                send_at:
                  type: integer
                  description: 'The time when Nylas should send the message, in seconds using the Unix timestamp format.

                    Must be at least one minute in the future from the time you make your request. You can

                    schedule a message to be sent up to 30 days in the future. If the request includes

                    `tracking_options.domain_name`, Nylas validates the hostname when it creates the schedule

                    and revalidates it before delivery.'
                subject:
                  type: string
                  description: The subject line of the message.
                  example: 'Reminder: Annual Philosophy Club meeting'
                template:
                  type: object
                  description: The [template](/docs/reference/api/application-level-templates/) to use for the message. Can be overriden by the `body` and `subject` fields.
                  properties:
                    id:
                      type: string
                      description: The template ID.
                      example: b79c82b2-a51b-4c54-8469-28006a43551a
                    strict:
                      type: boolean
                      description: 'When `true`, Nylas returns an error if the template contains variables that aren''t

                        defined in the `variables` object.'
                      default: true
                      example: true
                    variables:
                      type: object
                      description: 'A set of key/value pairs representing variables to substitute for values in the

                        template.'
                      additionalProperties:
                        type: string
                      example:
                        user:
                          name: Leyah
                          surname: Miller
                to:
                  type: array
                  description: A list of recipients for the message.
                  items:
                    type: object
                    properties:
                      email:
                        type: string
                        description: The recipient's email address.
                        example: leyah@example.com
                      name:
                        type: string
                        description: The recipient's name.
                        example: Leyah Miller
                tracking_options:
                  type: object
                  description: Tracking settings for the message. See [Track messages](/docs/v3/email/message-tracking/).
                  properties:
                    opens:
                      type: boolean
                      description: 'When `true`, enables

                        [message open tracking](/docs/v3/email/message-tracking/#message-open-tracking) on the

                        message. Nylas generates a

                        [`message.opened` webhook notification](/docs/reference/notifications/#message-opened-notifications)

                        when a participant first opens the message.'
                      default: false
                    links:
                      type: boolean
                      description: 'When `true`, enables

                        [link clicked tracking](/docs/v3/email/message-tracking/#link-clicked-tracking) on the

                        message. Nylas generates a

                        [`message.link_clicked` webhook notification](/docs/reference/notifications/#link-clicked-notifications)

                        when a participant clicks a link in the message.'
                      default: false
                    label:
                      type: string
                      description: 'A brief description of the message, why it''s being tracked, or the tracking options

                        enabled.'
                      maxLength: 2048
                    domain_name:
                      $ref: '#/components/schemas/tracking_domain_name'
          multipart/form-data:
            schema:
              type: object
              properties:
                attachment:
                  type: string
                  description: The content of the attachment (if available), in binary format.
                  format: binary
                message:
                  type: object
                  properties:
                    bcc:
                      type: array
                      description: A list of people to be BCC'd on the message.
                      items:
                        type: object
                        properties:
                          email:
                            type: string
                            description: The recipient's email address.
                            example: leyah@example.com
                          name:
                            type: string
                            description: The recipient's name.
                            example: Leyah Miller
                    body:
                      type: string
                      description: The HTML-formatted body of the message.
                      example: Looking forward to seeing you!
                    cc:
                      type: array
                      description: A list of people to be CC'd on the message.
                      items:
                        type: object
                        properties:
                          email:
                            type: string
                            description: The recipient's email address.
                            example: leyah@example.com
                          name:
                            type: string
                            description: The recipient's name.
                            example: Leyah Miller
                    custom_headers:
                      type: array
                      description: An array of custom headers to add to the message.
                      items:
                        type: object
                        properties:
                          name:
                            type: string
                            description: The header name.
                            example: Email-Campaign
                          value:
                            type: string
                            description: The header value.
                            example: meetings
                    from:
                      type: object
                      description: Information about the person sending the message.
                      properties:
                        email:
                          type: string
                          description: 'The sender''s email address. Must belong to an email domain that''s been verified

                            with Nylas.'
                          example: nyla@example.com
                        name:
                          type: string
                          description: The sender's name.
                          example: Nyla
                    is_plaintext:
                      type: boolean
                      description: 'When `true`, Nylas sends the message body as plain text and the MIME data doesn''t

                        include an HTML version of the message. When `false`, Nylas sends the message body as

                        HTML.'
                      default: false
                      example: true
                    metadata:
                      $ref: '#/components/schemas/metadata'
                    reply_to:
                      type: array
                      description: A list of people who should receive replies to the message by default.
                      items:
                        type: object
                        properties:
                          name:
                            type: string
                            description: The name of the person who should receive replies to the message.
                            example: Leyah Miller
                          email:
                            type: string
                            description: The email address of the person who should receive replies to the message.
                            example: leyah@example.com
                    reply_to_message_id:
                      type: string
                      description: 'The ID of the message you are replying to. If you are using a message that was sent using Nylas''

                        Transactional Send, you may use the ID that was returned in the Nylas response. For all other

                        messages, this is the [RFC822](https://datatracker.ietf.org/doc/html/rfc822#section-4.6.1)

                        `Message-ID` header of the message you''re replying to.'
                    send_at:
                      type: integer
                      description: 'The time when Nylas should send the message, in seconds using the Unix timestamp format.

                        Must be at least one minute in the future from the time you make your request. You can

                        schedule a message to be sent up to 30 days in the future. If the request includes

                        `tracking_options.domain_name`, Nylas validates the hostname when it creates the schedule

                        and revalidates it before delivery.'
                    subject:
                      type: string
                      description: The subject line of the message.
                      example: 'Reminder: Annual Philosophy Club meeting'
                    template:
                      type: object
                      description: The [template](/docs/reference/api/application-level-templates/) to use for the message. Can be overriden by the `body` and `subject` fields.
                      properties:
                        id:
                          type: string
                          description: The template ID.
                          example: b79c82b2-a51b-4c54-8469-28006a43551a
                        strict:
                          type: boolean
                          description: 'When `true`, Nylas returns an error if the template contains variables that aren''t

                            defined in the `variables` object.'
                          default: true
                          example: true
                        variables:
                          type: object
                          description: 'A set of key/value pairs representing variables to substitute for values in the

                            template.'
                          additionalProperties:
                            type: string
                          example:
                            user:
                              name: Leyah
                              surname: Miller
                    to:
                      type: array
                      description: A list of recipients for the message.
                      items:
                        type: object
                        properties:
                          email:
                            type: string
                            description: The recipient's email address.
                            example: leyah@example.com
                          name:
                            type: string
                            description: The recipient's name.
                            example: Leyah Miller
                    tracking_options:
                      type: object
                      description: Tracking settings for the message. See [Track messages](/docs/v3/email/message-tracking/).
                      properties:
                        opens:
                          type: boolean
                          description: 'When `true`, enables

                            [message open tracking](/docs/v3/email/message-tracking/#message-open-tracking) on the

                            message. Nylas generates a

                            [`message.opened` webhook notification](/docs/reference/notifications/#message-opened-notifications)

                            when a participant first opens the message.'
                          default: false
                        links:
                          type: boolean
                          description: 'When `true`, enables

                            [link clicked tracking](/docs/v3/email/message-tracking/#link-clicked-tracking) on the

                            message. Nylas generates a

                            [`message.link_clicked` webhook notification](/docs/reference/notifications/#link-clicked-notifications)

                            when a participant clicks a link in the message.'
                          default: false
                        label:
                          type: string
                          description: 'A brief description of the message, why it''s being tracked, or the tracking options

                            enabled.'
                          maxLength: 2048
                        domain_name:
                          $ref: '#/components/schemas/tracking_domain_name'
      x-code-samples:
      - lang: bash
        label: cURL
        source: "curl --request POST \\\n  --url 'https://api.us.nylas.com/v3/domains/<DOMAIN_NAME>/messages/send' \\\n  --header 'Accept: application/json' \\\n  --header 'Authorization: Bearer <NYLAS_API_KEY>' \\\n  --header 'Content-Type: application/json' \\\n  --data '{\n    \"to\": [{\n        \"name\": \"Jane Doe\",\n        \"email\": \"jane.doe@example.com\"\n    }],\n    \"from\": {\n        \"name\": \"ACME Support\",\n        \"email\": \"support@acme.com\"\n    },\n    \"subject\": \"Welcome to ACME\",\n    \"body\": \"Welcome to ACME! We'\\''re here to help you.\"\n}'"
      - lang: python
        label: Python SDK
        source: "from nylas import Client\n\nnylas = Client(\n    \"<NYLAS_API_KEY>\",\n    \"<NYLAS_API_URI>\",\n)\n\nmessage = nylas.transactional_send.send(\n    domain_name=\"<DOMAIN_NAME>\",\n    request_body={\n        \"to\": [{\"name\": \"Jane Doe\", \"email\": \"jane.doe@example.com\"}],\n        \"from_\": {\"name\": \"ACME Support\", \"email\": \"support@acme.com\"},\n        \"subject\": \"Welcome to ACME\",\n        \"body\": \"Welcome to ACME! We're here to help you.\",\n    },\n)\n\nprint(message)\n"
      responses:
        '200':
          description: Success. Returns message.
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    $ref: '#/components/schemas/transactional_send_message'
                  request_id:
                    type: string
                    description: The request ID.
                    example: 9ca1d434-5ac7-4331-b8fb-3749c9a758d3
        '400':
          $ref: '#/components/responses/400'
        '409':
          $ref: '#/components/responses/409_idempotent'
components:
  schemas:
    transactional_send_message:
      type: object
      properties:
        id:
          type: string
          description: The message ID.
          example: 6c45fe5e-0bb6-41b9-9acc-ccb15bfc51eb
        attachments:
          type: array
          description: An array of Attachment objects. For google, linked Google Drive files are not included. For Microsoft, linked One Drive files are not included.
          items:
            $ref: '#/components/schemas/attachment_transactional_send'
          uniqueItems: true
          minItems: 0
          example:
          - content_disposition: attachment
            content_type: text/calendar
            filename: null
            content_id: 4kj2jrcoj9ve5j9yxqz5cuv98
            size: 1708
          - content_disposition: attachment
            content_type: application/ics
            filename: invite.ics
            content_id: 70jcsv367jaiavt4njeu4xswg
            size: 1708
        bcc:
          type: array
          description: 'An array of name/email address pairs that the message was BCC''d to. For received messages, this

            is nearly always empty.'
          items:
            $ref: '#/components/schemas/message-participant'
        body:
          type: string
          description: The body of the message. This field is the same as the `body` field in your request.
          example: Hello, I just sent a message using Nylas!
        cc:
          type: array
          description: An array of name/email address pairs that the message was CC'd to.
          items:
            $ref: '#/components/schemas/message-participant'
        from:
          type: array
          description: A list of name/email address pairs that the message was sent from. For transactional send, this will always be one pair.
          items:
            $ref: '#/components/schemas/message-participant-response'
          uniqueItems: true
        object:
          type: string
          description: The object type of the response (in this case, `message`).
          example: message
        reply_to:
          type: array
          items:
            $ref: '#/components/schemas/message-participant'
          uniqueItems: true
          description: An array of name/email address pairs that should receive replies to the message.
        snippet:
          type: string
          minLength: 1
          description: 'A short snippet (the first 100 characters, with HTML tags removed) of the message body. This is

            useful for displaying a preview of the message.'
          example: 'You have been invited to the following event. Welcome! WhenThu Oct 28, 2021 7am - 8am Eastern

            Time - Toronto Joining info'
        subject:
          type: string
          description: The subject of the message.
          example: Nylas Send v3 Email
        tracking_options:
          type: object
          description: Tracking options for the message.
          properties:
            opens:
              type: boolean
              description: When `true`, shows that message open tracking is enabled.
              example: true
            links:
              type: boolean
              description: When `true`, shows that link clicked tracking is enabled.
              example: true
            label:
              type: string
              description: A label describing the message tracking purpose.
              maxLength: 2048
              example: Tracking test
        to:
          type: array
          description: An array of name/email address pairs that the message was sent to.
          items:
            $ref: '#/components/schemas/message-participant'
          uniqueItems: true
    metadata:
      title: Metadata
      type: object
      description: 'The metadata associated with the object. For more information, see

        [Metadata](/docs/reference/api/#metadata).'
      additionalProperties:
        type: string
        description: A key-value pair.
        maxLength: 500
      maxProperties: 50
    tracking_domain_name:
      type: string
      minLength: 1
      maxLength: 253
      example: tracking.example.com
      description: 'The custom hostname to use for link click and message open tracking. The hostname must be

        registered to the authenticated organization in the

        [Nylas Dashboard](https://dashboard-v3.nylas.com/organization/domains?tab=hosted-auth) and have an

        active certificate.


        Custom tracking hostnames are available on select plans. Contact your Nylas account representative

        or the [Nylas Sales team](https://www.nylas.com/contact-sales/) to enable this feature for your

        organization.


        Nylas trims surrounding whitespace, removes one trailing dot, and converts ASCII letters to

        lowercase before looking up the hostname. Provide an ASCII fully qualified hostname without a URL

        scheme, path, port, or wildcard.


        You must enable `links`, `opens`, or both when you provide this field. A custom tracking hostname

        does not support `thread_replies` by itself. If you omit this field, Nylas uses its regional

        tracking hostname. Invalid, inactive, blocked, deleted, and unowned hostnames return the same

        generic `400` response. If Nylas cannot complete the explicit ownership and certificate lookup, it

        returns a `5xx` response without falling back to a Nylas hostname.'
    message-participant:
      title: Message participant
      type: object
      description: A name/email address pair.
      properties:
        name:
          type: string
          example: Jon Snow
        email:
          type: string
          format: email
          example: jon.snow@example.com
      required:
      - email
    attachment_transactional_send:
      description: A file attachment for a transactional email message.
      type: object
      properties:
        content_type:
          type: string
          minLength: 1
          description: 'The [MIME type](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types) of the attachment, used by the email client to determine how to display the attachment. If you don''t provide a type, Nylas infers it from the file name.

            The value of this field is exactly the same as the email attachment''s `Content-Type` header.

            The provider might set additional parameters, such as `name` and `charset`.


            Nylas returns an empty `content_type` field if an attachment file name contains non-ASCII characters (for example, accented characters like `ü`). This is because Google can''t detect its content type.'
          example: image/png; name="pic.png"
        filename:
          type: string
          minLength: 1
          description: The file name of the attachment.
          example: pic.png
        content_id:
          type: string
          description: '(Inline attachments only) The alphanumeric `cid` from the `<img>` tag in the message''s HTML. For

            example, you might see something like `<img src=\"cid:ce9b9547-9eeb-43b2-ac4e-58768bdf04e4\">` in

            the message body.


            Sometimes, the `content_id` value is contained in angle brackets (for example,

            `<ce9b9547-9eeb-43b2-ac4e-58768bdf04e4>`).'
          example: 1234567890
        content_disposition:
          type: string
          description: (Not supported for Microsoft and EWS) The content disposition of the attachment. Usually, this is `inline` or `attachment` followed by the file name (for example, `inline; filename="some-image.jpeg"`).
          example: inline
        is_inline:
          type: boolean
          description: If `true`, indicates that the attachment is an inline file.
          example: true
        size:
          type: integer
          description: The size of the attachment, in bytes.
          example: 13068
    message-participant-response:
      title: Message participant response
      type: object
      description: A name/email address pair.
      properties:
        name:
          type: string
          example: Jon Snow
        email:
          type: string
          format: email
          example: jon.snow@example.com
  responses:
    '400':
      description: Bad Request
      content:
        application/json:
          schema:
            title: error
            type: object
            properties:
              request_id:
                type: string
                description: The request ID.
              error:
                type: object
                description: The response error object.
                properties:
                  type:
                    type: string
                    description: The error type.
                  message:
                    type: string
                    description: The error message.
                  provider_error:
                    type: object
                    description: The error from the provider.
          examples:
            Bad Request:
              value:
                request_id: 5fa64c92-e840-4357-86b9-2aa364d35b88
                error:
                  type: invalid_request_error
                  message: error parsing request body
                  provider_error:
                    code: TargetIdShouldNotBeMeOrWhitespace
                    message: Id is malformed.
            Invalid Idempotency-Key:
              value:
                request_id: 5fa64c92-e840-4357-86b9-2aa364d35b88
                error:
                  type: api.invalid_idempotency_key
                  message: Idempotency-Key must be 256 characters or fewer.
    409_idempotent:
      description: Conflict. Returned when an `Idempotency-Key` conflicts with an existing entry.
      content:
        application/json:
          schema:
            title: error
            type: object
            properties:
              request_id:
                type: string
                description: The request ID.
              error:
                type: object
                description: The response error object.
                properties:
                  type:
                    type: string
                    description: The error type.
                  message:
                    type: string
                    description: The error message.
          examples:
            Different payload, same key:
              value:
                request_id: 5fa64c92-e840-4357-86b9-2aa364d35b88
                error:
                  type: api.invalid_idempotent_request
                  message: The Idempotency-Key was reused with a different request payload. Use a different key, or match the original payload.
            Concurrent request in flight:
              value:
                request_id: 5fa64c92-e840-4357-86b9-2aa364d35b88
                error:
                  type: api.concurrent_idempotent_request
                  message: A request with the same Idempotency-Key is currently in progress. Wait a moment and retry with the same key.
  securitySchemes:
    ACCESS_TOKEN:
      scheme: bearer
      type: http
      bearerFormat: NYLAS_ACCESS_TOKEN
      description: 'The Nylas **access token** for a specific grant. Issued as part of OAuth 2.1 flow token

        exchange.'
    NYLAS_API_KEY:
      scheme: bearer
      type: http
      bearerFormat: NYLAS_API_KEY
      description: 'The Nylas **API key** provides application-level access to APIs and all grants. You can

        generate these from the Dashboard. Learn more about [authorizing requests](/docs/v3/auth/).'
    SCHEDULER_SESSION_TOKEN:
      scheme: bearer
      type: http
      bearerFormat: Session ID
      description: The Nylas Scheduler **session ID** that Scheduler UI Components use to authorize API requests.