Clickup

REST API at api.clickup.com/api/v2/ with resource-oriented endpoints. The workspace hierarchy (Workspace → Space → Folder → List → Task) requires agents to traverse or know the correct IDs at each level — more overhead than flat task-list models. Task creation requires a list_id. Subtasks are modeled as tasks with a parent field. Custom fields support text, number, dropdown, checkbox, date, and relationship types. The API supports filtering tasks by status, assignee, tag, due date, and custom fields. Webhooks cover task lifecycle events. Time tracking has dedicated endpoints. The Docs API is newer and less mature. Rate limits are 100 requests per minute per token for most endpoints. Pagination uses page-based pagination with some endpoints supporting cursor-based access.

ClickUp offers one of the broadest feature sets in project management — tasks, docs, goals, whiteboards, time tracking, forms, and dashboards — with an API that covers most of these surfaces. For agents, this breadth is both powerful and complex: the hierarchy (Workspace → Space → Folder → List → Task) has more nesting than competitors, meaning agents must navigate more levels to create or query tasks. The Task API is the primary integration point: create, update, query, and manage task dependencies, custom fields, checklists, and comments. Custom fields are extensively supported, enabling agents to store structured data on tasks. The main challenge is API consistency — some endpoints follow v2 patterns, others feel like v1 holdovers, and response shapes vary.

Personal API tokens (generated in Settings → Apps) provide full workspace access via Authorization header. OAuth 2.0 is available for marketplace apps with authorization code flow. Personal tokens don't expire and have the same permissions as the user — admin tokens can do everything. OAuth scopes are not granularly documented, making it hard to restrict agent permissions precisely. For internal agents, personal tokens are the quick path. Team-shared tokens aren't a built-in concept — agents serving multiple users need OAuth. No API key rotation mechanism. Webhook secrets are used for payload verification. IP restriction is not available at the API level.

API documentation at clickup.com/api/ provides endpoint reference with parameter descriptions and response examples. The interactive API reference lets users make test calls with their token. Documentation covers the workspace hierarchy, task operations, and webhooks. However, some advanced features (custom field types, formula fields, relationship fields) have thinner documentation. No official SDKs — community libraries exist for Python, Node, and Ruby with varying maintenance levels. The ClickUp University provides video tutorials focused on the UI rather than API. Developer community forums exist but are less active than Asana's or Jira's. For agents, the documentation is adequate for core task management but agents using advanced features may need to reverse-engineer behavior from API responses.

API errors return JSON with err field (string) and ECODE (error code string). Error codes like 'OAUTH_027' or 'ITEM_028' are ClickUp-specific and not always documented — agents may encounter error codes without clear resolution guidance. Rate limit is 100 requests per minute per token, returning 429 with an err message. This limit is tighter than many competitors and constrains bulk operations. Bulk task creation isn't available — agents must create tasks individually and throttle. Webhook delivery retries on failure. Task query performance degrades on very large lists. The API can return inconsistent response formats on some endpoints — agents should handle defensive parsing. Error documentation exists but could be more comprehensive.