---
title: "Link a task to an entity"
method: POST
path: "/companies/{company}/tasks/{task}/entity-links"
tags: ["Tasks"]
---

# Link a task to an entity

`POST /companies/{company}/tasks/{task}/entity-links`

## Request

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

Link a task to a Factuarea entity (`entity_type` + `entity_id`). An entity that does not exist, belongs to another company or whose module is not accessible returns 404 `linked_entity_not_found`. Linking it again returns the existing link.

## Path parameters

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

## Headers

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

## Request body

- LinkTaskToEntityV1Request
  - `entity_type` 'invoice' | 'quote' | 'proforma' | 'delivery_note' | 'purchase_invoice' | 'recurring_invoice' | 'contact' | 'product' | 'employee', required: Entity type: `invoice`, `quote`, `proforma`, `delivery_note`, `purchase_invoice`, `recurring_invoice`, `contact`, `product` or `employee`.
  - `entity_id` string, uuid, required: Public identifier (UUID v7) of the company entity.

## Response `201`

- object
  - `data` TaskEntityLink, required: A link between a task and a Factuarea entity (document, contact, product or employee).
    - `id` string, uuid, required: UUID v7 of the link.
    - `object` 'task_entity_link', required: Stripe-like discriminator. Always `task_entity_link` for this resource.
    - `task_id` string, uuid, required: UUID of the task.
    - `entity_type` 'invoice' | 'quote' | 'proforma' | 'delivery_note' | 'purchase_invoice' | 'recurring_invoice' | 'contact' | 'product' | 'employee', required: Type of the linked entity.
    - `entity_id` string, uuid, required: UUID of the linked entity.
    - `available` boolean, required: `false` when the entity was deleted or its module is no longer accessible, or when the key lacks the read scope of the entity resource (for example `invoices:read`); the link is still returned, with `summary: null`.
    - `summary` object, nullable, required: Display data of the entity, or `null` when it is not available.
      - `title` string, required
      - `number` string, nullable, required: Document number, or `null`.
      - `status` string, nullable, required: Public status of the entity, or `null`.
    - `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.
- `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)