---
title: "Link documents to a document"
method: POST
path: "/api/v1/rest/documents/{id}/links"
tags: ["Documents"]
---

# Link documents to a document

`POST /api/v1/rest/documents/{id}/links`

## Request

- Base URL: `https://api.custodo.ai`
- URL: `https://api.custodo.ai/api/v1/rest/documents/{id}/links`
- Auth: HTTP bearer

States that documents go together — a completion certificate and the signed contract, an invoice and its order, an annex and its contract. A link is undirected (both documents list each other) and sits beside the records: neither document changes, so this is allowed on sealed documents too. Linking a pair that is already linked changes nothing. At most 20 documents per call; each must be one the caller can see. Refused when the caller may only read the class of the document named in `id`.

## Path parameters

- `id` string, uuid, required

## Headers

- `X-Tenant-Id` string, uuid

## Request body

- object
  - `linked_ids` string[], required: The documents that go with it, from documents_search.

## Response `200`

Done. `data` is the tool’s own answer.

- RestResult
  - `ok` true, required
  - `data` unknown, required

## Other responses

- `400`: The arguments did not validate: `error.message` names the field, what it expects and what arrived.
- `401`: No API key, or one that is malformed, unknown, revoked or expired.
- `403`: The call never ran: the module is off for this organisation, the credential lacks the permission or the module, the tier does not cover it, or the tool is destructive and the key was not minted for that.
- `404`: Nothing with that id in this organisation.
- `409`: The record is in a state that does not allow it — under legal hold, already sent, already closed. `error.code` says which.
- `422`: The tool ran and refused, in a sentence of its own (`TOOL_REFUSED`): the message says what to change. Retrying the same call will not help.
- `429`: The API key has spent its minute, or its day. Every request a key makes counts. See `Retry-After`.

---

[API](https://skmtc.dev/custodo/apis/custodo-integrazioni.md) · [All operations](https://skmtc.dev/custodo/apis/custodo-integrazioni/llms.txt) · [OpenAPI document](https://skmtc.dev/custodo/apis/custodo-integrazioni/revisions/16d336d3ec2a?raw)