Basecamp To-Do Lists API
Manage to-do lists within a to-do set
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OpenAPI Specification
openapi: 3.2.0
info:
title: Basecamp To-Do Lists 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: To-Do Lists
description: Manage to-do lists within a to-do set
paths:
/todosets/{todosetId}/todolists.json:
get:
operationId: listTodoLists
summary: List to-do lists
description: Returns a paginated list of active to-do lists within the specified to-do set.
tags:
- To-Do Lists
parameters:
- $ref: '#/components/parameters/TodosetId'
- name: status
in: query
required: false
description: Filter by status.
schema:
type: string
enum:
- archived
- trashed
responses:
'200':
description: List of to-do lists
content:
application/json:
schema:
type: array
items:
$ref: '#/components/schemas/TodoList'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
post:
operationId: createTodoList
summary: Create a to-do list
description: Creates a new to-do list in the specified to-do set with the given name and optional description.
tags:
- To-Do Lists
parameters:
- $ref: '#/components/parameters/TodosetId'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/TodoListCreateRequest'
responses:
'201':
description: To-do list created
content:
application/json:
schema:
$ref: '#/components/schemas/TodoList'
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
/todolists/{todolistId}.json:
get:
operationId: getTodoList
summary: Get a to-do list
description: Returns the to-do list with the given ID.
tags:
- To-Do Lists
parameters:
- $ref: '#/components/parameters/TodolistId'
responses:
'200':
description: To-do list details
content:
application/json:
schema:
$ref: '#/components/schemas/TodoList'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
put:
operationId: updateTodoList
summary: Update a to-do list
description: Updates the name and description of the specified to-do list.
tags:
- To-Do Lists
parameters:
- $ref: '#/components/parameters/TodolistId'
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/TodoListCreateRequest'
responses:
'200':
description: Updated to-do list
content:
application/json:
schema:
$ref: '#/components/schemas/TodoList'
'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'
TodoListCreateRequest:
type: object
required:
- name
properties:
name:
type: string
description: To-do list name
description:
type: string
description: Optional description with supported HTML formatting
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
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
TodoList:
allOf:
- $ref: '#/components/schemas/Recording'
- type: object
properties:
completed:
type: boolean
description: Whether all to-dos in this list are completed
completed_ratio:
type: string
description: Completion ratio as a string (e.g., "2/5")
position:
type: integer
description: Display position within the to-do set
color:
type: string
description: List color identifier
nullable: true
todos_url:
type: string
format: uri
description: API URL to list to-dos in this list
comments_count:
type: integer
description: Number of comments on this list
boosts_count:
type: integer
description: Number of boosts on this list
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:
TodolistId:
name: todolistId
in: path
required: true
description: Unique identifier of the to-do list
schema:
type: integer
TodosetId:
name: todosetId
in: path
required: true
description: Unique identifier of the to-do set
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