Flux Board

Manage Flux kanban boards, cards, columns, and labels through the Flux REST API. Create and move cards, assign members, toggle labels, search, and build board automations.

Flux

Flux is a kanban board management platform. Use this skill to build automations, manage cards, and organize work through the Flux REST API.

Setup

• FLUX_API_KEY (required) — an API key beginning with flux_. Every request is authenticated with it.
• FLUX_BASE_URL (optional) — the origin of the Flux instance, e.g. https://flux.umin.ai. Defaults to https://flux.umin.ai.

Authentication

Send the key as a Bearer token on every request:

Authorization: Bearer flux_YOUR_KEY

API keys carry granular scopes, so a request may succeed for reads but be rejected for writes if the key lacks the scope. A 401 means the key is missing or invalid; a 403 means the key is valid but not permitted for that action.

Core concepts

• Active workspace — most board/card endpoints operate on the active workspace tied to the key. List workspaces with GET /api/workspaces, change it with POST /api/workspaces/switch.
• Two ID formats — boards accept either a UUID or a short URL id (shortId, e.g. av-tX6qQ). Cards have an internal UUID and a human id (humanId, e.g. TB-1) used in URLs. Use the UUID for write operations unless an endpoint says otherwise.
• Cache key gotcha — a board is keyed by its shortId, not by card.boardId (which is a UUID). Don't assume the two are interchangeable when matching a card to its board.
• Soft deletes — every DELETE is reversible. Deleted records are hidden, not destroyed, and can be restored via POST /api/undo.
• Idempotency — include X-Idempotency-Key: <uuid> on every write (POST/PATCH/PUT/ DELETE). On retry, Flux returns the original result instead of duplicating the action.
• Dates — all timestamps are ISO 8601.

Endpoints

Workspaces

Method	Path	Body / Query	Notes
GET	/api/workspaces	—	List your workspaces → { workspaces: [{ id, name, slug }] }
POST	/api/workspaces	{ name }	Create a workspace
POST	/api/workspaces/switch	{ workspaceId }	Set the active workspace

Boards

Method	Path	Body / Query	Notes
GET	/api/boards	—	Boards in the active workspace → { boards: [{ id, shortId, title, columns }] }
GET	/api/boards/all	—	Boards across all workspaces
POST	/api/boards	{ title, workspaceId? }	Create a board
GET	/api/boards/{boardId}	accepts shortId or UUID	Full board → { board, cards: { [cardId]: card }, boardLabels, members }
PATCH	/api/boards/{boardId}	{ title?, settings?, doneColumnId? }	Update a board
DELETE	/api/boards/{boardId}	—	Soft-delete a board

Columns

Method	Path	Body / Query	Notes
POST	/api/columns	{ boardId, title }	Create a column
PATCH	/api/columns	{ columnId, title?, isDone? }	Update a column
DELETE	/api/columns?columnId={id}	—	Delete a column
PUT	/api/columns/reorder	{ boardId, columnIds: [ordered UUIDs] }	Reorder columns

Cards

Method	Path	Body / Query	Notes
POST	/api/cards	{ boardId, columnId, title, description? }	Create a card
PATCH	/api/cards	{ cardId, title?, description?, columnId?, assignees?, dueDate?, coverUrl?, archivedAt? }	Update a card. assignees is an array of user IDs and replaces the whole set.
DELETE	/api/cards?cardId={id}	—	Soft-delete a card
GET	/api/cards/{cardId}	—	Full detail: checklist, comments, attachments, labels, assignees
PUT	/api/cards/reorder	{ boardId, moves: [{ cardId, columnId, position }] }	Move/reorder cards

Card sub-resources

Checklist

Method	Path	Body / Query
POST	/api/cards/{cardId}/checklist	{ text }
PATCH	/api/cards/{cardId}/checklist	{ itemId, text?, done?, position? }
DELETE	/api/cards/{cardId}/checklist?itemId={id}	—

Comments

Method	Path	Body / Query
POST	/api/cards/{cardId}/comments	{ content, parentId? }
PATCH	/api/cards/{cardId}/comments	{ commentId, content }
DELETE	/api/cards/{cardId}/comments?commentId={id}	—

Labels on a card (toggle a board-level label onto the card)

Method	Path	Body / Query
POST	/api/cards/{cardId}/labels	{ labelId }
DELETE	/api/cards/{cardId}/labels?labelId={id}	—

Attachments

Method	Path	Body / Query	Notes
POST	/api/cards/{cardId}/attachments/upload-url	{ fileName, mimeType }	Returns a presigned S3 upload URL
POST	/api/cards/{cardId}/attachments	{ fileName, fileUrl, s3Key?, mimeType? }	Register the attachment after uploading
DELETE	/api/cards/{cardId}/attachments?attachmentId={id}	—	Delete an attachment

Labels (board-level definitions)

Method	Path	Body / Query
POST	/api/boards/{boardId}/labels	{ text, color }
PATCH	/api/boards/{boardId}/labels	{ labelId, text?, color? }
DELETE	/api/boards/{boardId}/labels?labelId={id}	—

Search & undo

Method	Path	Body / Query	Notes
GET	/api/search?q={query}&workspaceId={id?}&type={card|board?}	—	Full-text search
POST	/api/undo	{ boardId }	Undo the last action on a board

Common workflows

Create a card on a board

1. GET /api/boards — find the board by title, note its shortId.
2. GET /api/boards/{shortId} — read board.columns to pick the target columnId.
3. POST /api/cards with { boardId, columnId, title }.

Move a card to another column

1. GET /api/boards/{shortId} — find the source/target columnIds and the card.
2. PUT /api/cards/reorder with { boardId, moves: [{ cardId, columnId, position: 0 }] } (position: 0 drops it at the top of the target column).

Assign members to a card

1. GET /api/boards/{shortId} — the response members array lists user IDs.
2. PATCH /api/cards with { cardId, assignees: [userId1, userId2] }. Assignees are replaced wholesale — send the full desired list, not a delta. Note: the write field is assignees; board reads expose the same data as assigneeIds. Sending assigneeIds to PATCH is silently ignored and returns 422 "No updates provided".

Add a label to a card

1. GET /api/boards/{shortId} — the response boardLabels array lists label IDs. (Create the label first with POST /api/boards/{boardId}/labels if it doesn't exist.)
2. POST /api/cards/{cardId}/labels with { labelId }.

Notes & gotchas

• Always send X-Idempotency-Key: <uuid> on writes to make retries safe.
• All deletes are soft and reversible via POST /api/undo.
• Board IDs accept both UUID and shortId; card IDs have a UUID and a humanId (TB-1).
• Resolve a board's columns and labels before creating or moving cards — you need their IDs from GET /api/boards/{shortId}.
• A 403 on a write usually means the API key lacks the required scope, not that the resource is missing.