Adds a file from a remote service


Method URL:
Preferred HTTP method:GET
Accepted content types:application/x-www-form-urlencoded
Rate limiting:Tier 2
Works with:
Token typeRequired scope(s)
classic botbot

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The add method adds a remote file to Slack. Adding a file does not share it to a channel. To make your beautiful remote file visible, use the files.remote.share method.

Remote files exist across the whole workspace (or organization, for Enterprise Grid). Because of that, remote files must be added by bots with the bot scope, not by an individual user.



Authentication token bearing required scopes.


Creator defined GUID for the file.


URL of the remote file.


Title of the file being shared.

ExampleDanger, High Voltage!

type of file


A text file (txt, pdf, doc, etc.) containing textual search terms that are used to improve discovery of the remote file.


Preview of the document via multipart/form-data.


Present arguments as parameters in application/x-www-form-urlencoded querystring or POST body. This method does not currently accept application/json.

preview_image is displayed when your remote file is shared. It's a binary image file.

external_id is the unique ID of the remote file, according to the external host of the file.

indexable_file_contents is a text file that represents the file for search. When a user searches in Slack, their query will be compared against the contents of this text file for matching. Think of this text file like the alt parameter on an HTML <img> tag — a textual representation of a non-textual object. The text file can contain a description of the remote file, or it can contain search keywords, or anything else text-based.

Note: this method performs an upsert. If you add a file that has been added before, the existing file will be updated.


        "ok": true,
        "file": {
            "id": "F0GDJ3XMH",
            "created": 1563919925,
            "timestamp": 1563919925,
            "name": "LeadvilleAndBackAgain",
            "title": "LeadvilleAndBackAgain",
            "mimetype": "application/vnd.slack-remote",
            "filetype": "remote",
            "pretty_type": "Remote",
            "user": "U0F8RBVNF",
            "editable": false,
            "size": 0,
            "mode": "external",
            "is_external": true,
            "external_type": "app",
            "is_public": false,
            "public_url_shared": false,
            "display_as_bot": false,
            "username": "",
            "url_private": "",
            "permalink": "",
            "comments_count": 0,
            "is_starred": false,
            "shares": {},
            "channels": [],
            "groups": [],
            "ims": [],
            "external_id": "1234",
            "external_url": "",
            "has_rich_preview": false

One tricky bit: in the response, the file object may indicate that "has_rich_preview" is false, even if you include preview_image. That's because it takes a few seconds for Slack to parse the preview_image you pass. If you call files.remote.add with the same external_id later, you'll see "has_preview_image": true.


This table lists the expected errors that this method could return. However, other errors can be returned in the case where the service is down or other unexpected factors affect processing. Callers should always check the value of the ok params in the response.


The uploaded image could not be processed - try passing a JPG or PNG


The uploaded image had excessive dimensions


The external_id provided is too long.


The title provided is too long.


No authentication token provided.


Some aspect of authentication cannot be validated. Either the provided token is invalid or the request originates from an IP address disallowed from making the request.


Authentication token is for a deleted user or workspace.


Authentication token is for a deleted user or workspace or the app has been removed.


The workspace token used in this request does not have the permissions necessary to complete the request. Make sure your app is a member of the conversation it's attempting to post a message to.


The workspace is undergoing an enterprise migration and will not be available until migration is complete.


Administrators have suspended the ability to post a message.


The token used is not granted the specific scope permissions required to complete this request.


The method was called with invalid arguments.


The method was passed an argument whose name falls outside the bounds of accepted or expected values. This includes very long names and names with non-alphanumeric characters other than _. If you get this error, it is typically an indication that you have made a very malformed API call.


The method was called via a POST request, but the charset specified in the Content-Type header was invalid. Valid charset names are: utf-8 iso-8859-1.


The method was called via a POST request with Content-Type application/x-www-form-urlencoded or multipart/form-data, but the form data was either missing or syntactically invalid.


The method was called via a POST request, but the specified Content-Type was invalid. Valid types are: application/json application/x-www-form-urlencoded multipart/form-data text/plain.


The method was called via a POST request and included a data payload, but the request did not include a Content-Type header.


The workspace associated with your request is currently undergoing migration to an Enterprise Organization. Web API and other platform operations will be intermittently unavailable until the transition is complete.


The method was called via a POST request, but the POST data was either missing or truncated.


The server could not complete your operation(s) without encountering a catastrophic error. It's possible some aspect of the operation succeeded before the error was raised.


The server could not complete your operation(s) without encountering an error, likely due to a transient issue on our end. It's possible some aspect of the operation succeeded before the error was raised.


This table lists the expected warnings that this method will return. However, other warnings can be returned in the case where the service is experiencing unexpected trouble.


The method was called via a POST request, and recommended practice for the specified Content-Type is to include a charset parameter. However, no charset was present. Specifically, non-form-data content types (e.g. text/plain) are the ones for which charset is recommended.


The method was called via a POST request, and the specified Content-Type is not defined to understand the charset parameter. However, charset was in fact present. Specifically, form-data content types (e.g. multipart/form-data) are the ones for which charset is superfluous.