API · Platform · Files
Create a file link.
Mint a short-lived signed URL that streams the bytes of a File. Used whenever a human or external system needs to download or display the file's contents — a stakeholder pulling a 409A report, a counterparty downloading a signed agreement, an external accountant fetching a tax document.
Why a separate endpoint: file metadata (size, type, linked resources) is freely retrievable, but the bytes themselves sit behind a signed-URL gate so the audit log can record exactly when and why they were accessed. The link's metadata is captured on the audit entry so a reviewer can answer "why did this file leave the system" three years later.
Default expiry - expires_in_seconds defaults to 3600 (1 hour). Maximum is 86400 (24 hours). Past the expiry, the URL returns 410 Gone. - For bytes that need indefinite hosting (a public-facing PDF, a reference document on a customer site), re-issue links — Matter intentionally rejects long-lived URLs.
Returns 200 OK with the signed url in the response body. The link is single-purpose; mint a fresh one for each new audience or use case so the audit log accurately attributes access.
See also: Files API overview.
Last updated
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
expires_in_secondsintegerOptionalmetadataobjectOptionalFlat string-to-string map. Up to 50 keys. Keys: max 40 chars, charset
[A-Za-z0-9_\\-.]. Values: max 500 chars. Keys prefixed matter_ are reserved
for platform use. Metadata is retrievable but not filterable via query params.
Response Body
application/json
application/problem+json
Request
curl -X POST "https://api.mattermode.com/v1/files/{id}/links" \ -H "Content-Type: application/json" \ -d '{ "expires_in_seconds": 3600, "metadata": {} }'const body = JSON.stringify({ "expires_in_seconds": 3600, "metadata": {}})fetch("https://api.mattermode.com/v1/files/{id}/links", { method: "POST", headers: { "Content-Type": "application/json" }, body})package mainimport ( "fmt" "net/http" "io/ioutil" "strings")func main() { url := "https://api.mattermode.com/v1/files/{id}/links" body := strings.NewReader(`{ "expires_in_seconds": 3600, "metadata": {} }`) req, _ := http.NewRequest("POST", url, body) req.Header.Add("Content-Type", "application/json") res, _ := http.DefaultClient.Do(req) defer res.Body.Close() body, _ := ioutil.ReadAll(res.Body) fmt.Println(res) fmt.Println(string(body))}import requestsheaders = { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10", "Idempotency-Key": "ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b",}payload = { "expires_in_seconds": 3600, "metadata": {}}resp = requests.post( "https://api.mattermode.com/v1/files/file_Y9rJpN4k/links", headers=headers, json=payload,)resp.raise_for_status()print(resp.json())import java.net.URI;import java.net.http.HttpClient;import java.net.http.HttpRequest;import java.net.http.HttpResponse;import java.net.http.HttpResponse.BodyHandlers;import java.time.Duration;import java.net.http.HttpRequest.BodyPublishers;var body = BodyPublishers.ofString("""{ "expires_in_seconds": 3600, "metadata": {}}""");HttpClient client = HttpClient.newBuilder() .connectTimeout(Duration.ofSeconds(10)) .build();HttpRequest.Builder requestBuilder = HttpRequest.newBuilder() .uri(URI.create("https://api.mattermode.com/v1/files/{id}/links")) .header("Content-Type", "application/json") .POST(body) .build();try { HttpResponse<String> response = client.send(requestBuilder.build(), BodyHandlers.ofString()); System.out.println("Status code: " + response.statusCode()); System.out.println("Response body: " + response.body());} catch (Exception e) { e.printStackTrace();}using System;using System.Net.Http;using System.Text;var body = new StringContent("""{ "expires_in_seconds": 3600, "metadata": {}}""", Encoding.UTF8, "application/json");var client = new HttpClient();var response = await client.PostAsync("https://api.mattermode.com/v1/files/{id}/links", body);var responseBody = await response.Content.ReadAsStringAsync();curl --request POST 'https://api.mattermode.com/v1/files/file_Y9rJpN4k/links' \ --header 'Authorization: Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc' \ --header 'Matter-Version: 2026-06-10' \ --header 'Idempotency-Key: ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b' \ --header 'Content-Type: application/json' \ --data '{ "expires_in_seconds": 3600, "metadata": {}}'const response = await fetch("https://api.mattermode.com/v1/files/file_Y9rJpN4k/links", { method: "POST", headers: { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10", "Idempotency-Key": "ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b", "Content-Type": "application/json", }, body: JSON.stringify({ "expires_in_seconds": 3600, "metadata": {} }),});if (!response.ok) { throw new Error(`Matter API ${response.status}: ${await response.text()}`);}const data = await response.json();console.log(data);Response
application/json{
"id": "string",
"object": "file_link",
"file_id": "string",
"url": "https://your.app/webhooks/matter",
"expires_at": 1745539200,
"metadata": {},
"created": 1745539200,
"livemode": false
}{
"type": "https://mattermode.com/docs/errors/not_found",
"title": "Not found",
"status": 404,
"code": "not_found",
"detail": "No entity with id `ent_Nq3KcAbc` is visible to this token.",
"doc_url": "https://mattermode.com/docs/guides/errors#not_found",
"request_id": "req_Qw9xYz8A"
}