Nylas

Nylas Messages API

Messages. List, search, read, update and delete email messages. Send immediately, schedule a send and cancel a scheduled send, with folders, signatures and attachments alongside.

GitHub OpenAPI

Operations 9

GET /v3/grants/{grant_id}/messages Return all Messages #
GET /v3/grants/{grant_id}/messages/{message_id} Return a Message #
PUT /v3/grants/{grant_id}/messages/{message_id} Update message attributes #
DELETE /v3/grants/{grant_id}/messages/{message_id} Delete a message #
PUT /v3/grants/{grant_id}/messages/clean Clean messages #
POST /v3/grants/{grant_id}/messages/send Send a Message #
GET /v3/grants/{grant_id}/messages/schedules Return scheduled messages #
GET /v3/grants/{grant_id}/messages/schedules/{scheduleId} Return a scheduled message #
DELETE /v3/grants/{grant_id}/messages/schedules/{scheduleId} Cancel a scheduled message #

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/nylas/refs/heads/main/openapi/nylas-messages-api-openapi.yml

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OpenAPI Specification

nylas-messages-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Nylas Messages 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:


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# Full source: https://raw.githubusercontent.com/api-evangelist/nylas/refs/heads/main/openapi/nylas-messages-api-openapi.yml