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OpenAPI Specification
openapi: 3.2.0
info:
title: Basecamp Messages API
description: The Basecamp API is a REST API that provides programmatic access to Basecamp's project management and team communication platform.
version: '1.0'
contact:
name: Basecamp Developer Support
url: https://github.com/basecamp/bc3-api
termsOfService: https://basecamp.com/terms
servers:
- url: https://3.basecampapi.com/{accountId}
description: Production Server
variables:
accountId:
description: Your Basecamp account ID
default: '999999999'
security:
- bearerAuth: []
tags:
- name: Messages
description: Manage messages on message boards
paths:
/message_boards/{messageBoardId}/messages.json:
get:
operationId: listMessages
summary: List messages
description: Returns a paginated list of active messages in the specified message board. Messages can be sorted by created_at or updated_at.
tags:
- Messages
parameters:
- $ref: '#/components/parameters/MessageBoardId'
- name: sort
in: query
description: Sort field.
required: false
schema:
type: string
enum:
- created_at
- updated_at
- name: direction
in: query
description: Sort direction.
required: false
schema:
type: string
enum:
- asc
- desc
responses:
'200':
description: List of messages
content:
application/json:
schema:
type: array
items:
$ref: '#/components/schemas/Message'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
post:
operationId: createMessage
summary: Create a message
description: Creates a new message in the specified message board. Set status to "active" to publish immediately; otherwise the message is saved as a draft.
tags:
- Messages
parameters:
- $ref: '#/components/parameters/MessageBoardId'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/MessageCreateRequest'
responses:
'201':
description: Message created
content:
application/json:
schema:
$ref: '#/components/schemas/Message'
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
/messages/{messageId}.json:
get:
operationId: getMessage
summary: Get a message
description: Returns the message with the given ID.
tags:
- Messages
parameters:
- $ref: '#/components/parameters/MessageId'
responses:
'200':
description: Message details
content:
application/json:
schema:
$ref: '#/components/schemas/Message'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
put:
operationId: updateMessage
summary: Update a message
description: Updates the subject, content, or category of the specified message.
tags:
- Messages
parameters:
- $ref: '#/components/parameters/MessageId'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/MessageUpdateRequest'
responses:
'200':
description: Updated message
content:
application/json:
schema:
$ref: '#/components/schemas/Message'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
components:
schemas:
Recording:
type: object
description: A generic recording object representing any Basecamp content resource such as a message, to-do, document, comment, or upload.
properties:
id:
type: integer
description: Recording ID
status:
type: string
description: Recording status
enum:
- active
- archived
- trashed
visible_to_clients:
type: boolean
description: Whether this recording is visible to client users
created_at:
type: string
format: date-time
description: Timestamp when the recording was created
updated_at:
type: string
format: date-time
description: Timestamp when the recording was last updated
title:
type: string
description: Title or summary of the recording
inherits_status:
type: boolean
description: Whether this recording inherits its status from a parent
type:
type: string
description: Recording type (e.g., Message, Todo, Document)
url:
type: string
format: uri
description: API URL for this recording
app_url:
type: string
format: uri
description: Web URL for this recording
bucket:
$ref: '#/components/schemas/BucketRef'
creator:
$ref: '#/components/schemas/PersonRef'
BucketRef:
type: object
description: Reference to the project (bucket) that contains a resource
properties:
id:
type: integer
description: Project ID
name:
type: string
description: Project name
type:
type: string
description: Resource type, always "Project"
url:
type: string
format: uri
description: API URL for the project
app_url:
type: string
format: uri
description: Web URL for the project
Error:
type: object
properties:
error:
type: string
description: Human-readable error message
MessageUpdateRequest:
type: object
properties:
subject:
type: string
description: Updated message subject
content:
type: string
description: Updated message body in HTML format
category_id:
type: integer
description: Updated message category ID
MessageCreateRequest:
type: object
required:
- subject
properties:
subject:
type: string
description: Message subject (title)
content:
type: string
description: Message body in HTML format
status:
type: string
description: Set to "active" to publish immediately
enum:
- active
- draft
category_id:
type: integer
description: Optional message category ID
subscriptions:
type: array
description: Person IDs to notify about this message
items:
type: integer
PersonRef:
type: object
description: Minimal reference to a Basecamp person
properties:
id:
type: integer
description: Person ID
attachable_sgid:
type: string
description: Signed global ID for attaching this person
name:
type: string
description: Full name
email_address:
type: string
format: email
description: Email address
personable_type:
type: string
description: Type of personable (User, Client, etc.)
title:
type: string
description: Job title
bio:
type: string
description: Short biography
location:
type: string
description: Location string
created_at:
type: string
format: date-time
description: Account creation timestamp
updated_at:
type: string
format: date-time
description: Last update timestamp
admin:
type: boolean
description: Whether the person is an account administrator
owner:
type: boolean
description: Whether the person is the account owner
client:
type: boolean
description: Whether the person is a client user
employee:
type: boolean
description: Whether the person is an employee
time_zone:
type: string
description: IANA time zone name
avatar_url:
type: string
format: uri
description: URL to the person's avatar image
company:
type: object
description: Company the person belongs to
properties:
id:
type: integer
description: Company ID
name:
type: string
description: Company name
Message:
allOf:
- $ref: '#/components/schemas/Recording'
- type: object
properties:
subject:
type: string
description: Message subject/title
content:
type: string
description: HTML-formatted message body
comments_count:
type: integer
description: Number of comments on this message
comments_url:
type: string
format: uri
description: API URL to list comments
boosts_count:
type: integer
description: Number of boosts (reactions) on this message
responses:
NotFound:
description: Not found — the requested resource does not exist
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
Unauthorized:
description: Unauthorized — missing or invalid Bearer token
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
BadRequest:
description: Bad request — missing required fields or invalid values
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
parameters:
MessageId:
name: messageId
in: path
required: true
description: Unique identifier of the message
schema:
type: integer
MessageBoardId:
name: messageBoardId
in: path
required: true
description: Unique identifier of the message board
schema:
type: integer
securitySchemes:
bearerAuth:
type: http
scheme: bearer
description: 'OAuth 2.0 Bearer token obtained via the Basecamp authorization code flow at launchpad.37signals.com. Include as "Authorization: Bearer {token}" in all requests.'
externalDocs:
description: Basecamp API Documentation
url: https://github.com/basecamp/bc3-api