---
title: "Create a task relation"
method: POST
path: "/companies/{company}/tasks/{task}/relations"
tags: ["Tasks"]
---

# Create a task relation

`POST /companies/{company}/tasks/{task}/relations`

## Request

- Base URL: `https://api.factuarea.com/v1`
- URL: `https://api.factuarea.com/v1/companies/{company}/tasks/{task}/relations`
- Auth: one of:
  - HTTP bearer
  - API key in header `X-API-Key`

Relate a task to another task of your company (`target_task_id`) with a `type`: `subtask`, `blocks` or `related`. A task cannot relate to itself (422 `task_self_relation`), a relation that would close a cycle is rejected (422 `task_relation_cycle`) and an existing one returns 409 `task_relation_exists`.

## Path parameters

- `company` string, uuid, required
- `task` string, uuid, required

## Headers

- `Idempotency-Key` string
- `Factuarea-Version` string, date

## Request body

- CreateTaskRelationV1Request
  - `target_task_id` string, uuid, required: Public identifier (UUID v7) of the target task of the relation, from the same company.
  - `type` 'subtask' | 'blocks' | 'related', required: Relation type: `subtask` (the target task is a subtask of the task in the path), `blocks` (the task in the path blocks the target task) or `related`.

## Response `201`

- object
  - `data` TaskRelation, required: A relation between two tasks, seen from the task of the request.
    - `id` string, uuid, required: UUID v7 of the relation.
    - `object` 'task_relation', required: Stripe-like discriminator. Always `task_relation` for this resource.
    - `type` 'subtask' | 'blocks' | 'related', required
    - `source_task_id` string, uuid, required: UUID of the source task (the parent, or the blocking task).
    - `target_task_id` string, uuid, required: UUID of the target task (the subtask, or the blocked task).
    - `direction` 'parent' | 'child' | 'blocks' | 'blocked_by' | 'related', required: What `related_task` is for the task of the request.
    - `related_task` object, required: The other task of the relation.
      - `id` string, uuid, required: UUID of the task.
      - `key` string, required
      - `title` string, required
      - `status` 'planned' | 'active' | 'archived', required: Board status: `planned` (backlog), `active` (in a column of the board) or `archived`.
      - `completed` boolean, required
      - `priority` 'none' | 'low' | 'medium' | 'high' | 'urgent', required: Task priority.
      - `assignee_id` string, uuid, nullable, required: UUID of the assigned member, or `null`.
      - `project_id` string, uuid, required: UUID of its project.
    - `created_at` string, date-time, required: Creation timestamp.

## Other responses

- `400`: `parameter_unknown` with `subcode` `retired_active_profile_header`: the retired `X-Active-Profile` header was sent; the company goes in the path. `parameter_invalid_format` on `Factuarea-Version`: the header is not a `YYYY-MM-DD` date. `unsupported_api_version`: the `Factuarea-Version` date is not a supported version.
- `401`: Missing or invalid API key.
- `403`: The request is authenticated but not allowed: the API key lacks the required scope (`insufficient_scope`), the plan does not include the public API or this feature (`addon_not_active`, `feature_not_available_in_plan`), or the module is not available with a test key (`module_not_available_in_sandbox`).
- `404`: The requested resource does not exist or belongs to another company.
- `409`: The request conflicts with data that already exists or with a request running at the same time. `task_relation_exists`: the two tasks are already related with that relation type. `resource_conflict`: another request was reserving identifiers for the same kind of record at that moment and this one could not complete its reservation. Nothing was written; send the request again after a few seconds.
- `422`: Validation failed. The `error.param` field identifies which input is invalid.
- `429`: Rate limit exceeded. Retry after the duration in `Retry-After`.
- `500`: Unexpected server error.

---

[API](https://skmtc.dev/factuarea/apis/factuarea-public-api.md) · [All operations](https://skmtc.dev/factuarea/apis/factuarea-public-api/llms.txt) · [OpenAPI document](https://skmtc.dev/factuarea/apis/factuarea-public-api/revisions/718e77934422?raw)