How to Automate Slack Canvases for Client Channels

What is a Slack canvas?

A canvas is a collaborative document that lives inside a Slack channel, like a page where you write in a mini document format. Slack has offered them since April 2023, and many agencies ignore them because they already use a project management tool, Notion or Google Docs.

If your client communication happens in Slack, a canvas is worth a second look. To add one by hand, open the channel, press the plus button, choose canvas and create a new one. Slack also provides templates, such as employee onboarding, newsletters and weekly syncs. Canvases support tick boxes, tables, user mentions, links and cards, and there is a lists feature too, though we do not use it.

What should a client channel canvas contain?

Our client canvas is a hub page. It works as a welcome page and a reference in one. We include:

• A welcome with the company name.
• Quick links, such as booking a call or opening the shared Google Drive.
• Project status: on track or delayed, plus the next check in call date and meeting link.
• An onboarding checklist the client can tick off.
• The team members they will deal with, including time zones.
• Communication guidelines, so clients know when to expect replies.
• A feedback section that points them to where to give feedback or get help, and a link to book a call.

Why add canvases to client channels?

Everything in one place. Resources scatter across many tools as a client relationship grows: video walkthroughs, documents, sheets, shared folders, feedback forms. A canvas gives clients one source of truth. If they know where to find something, they do not need to message you, so there are fewer delays and less back and forth, and your team spends less time acting as admin.

A client portal can do part of this, but ours is used to track project progress, not to store resources. A canvas fills that gap.

A better first impression. When a client joins Slack, the channel is usually empty apart from a few introductions. A canvas that shows who they work with, how to book a call and what to do first elevates the experience. Think of it like the FAQ section at the end of a sales page: it answers questions such as when the next call is, who they will speak to and how to give feedback. It also costs nothing extra, because the feature is already in Slack.

How do you automate canvas creation in Make.com?

For a long time we created canvases by hand each time we onboarded a client, because Make.com had no module for them. The automation below uses Slack's API instead. Any no code tool that can make API calls would do, such as Make.com, Zapier or n8n. The video above walks through the full build, and there is a free Make.com template for this guide.

In our example, a trigger sets the variables a real onboarding process would supply: the client name, a Slack channel ID, a Google Drive link, the next call date and a meeting link. We assume the channel already exists.

1. Connect Slack to Make.com using the Add button in a Slack module, and follow the pop up.
2. Add a Slack module to get a channel by its ID. This confirms the channel is found.
3. Add a Slack module to make an API call. Enter the relative path for creating a conversation canvas, set the method to POST, and in the body pass the channel ID and a canvas name taken from the client name variable. Slack's module handles authentication, so no headers are needed. A response with status code 200 means it worked, and you will see an empty canvas in the channel.
4. Add a second API call to edit the canvas, using the canvas ID returned by the first call. Set the method to POST again.
5. In the body, set where the change goes (at the end), the type (markdown) and the markdown content itself, with the client name, Drive link and call details as variables.

How do you write the markdown for the canvas?

Slack canvases require markdown, and specific elements such as cards need a specific format. The easiest route is to copy a canvas template, paste it into ChatGPT and ask it to rewrite the content for your agency in the same format. Then ask for it as a single line of markdown that you can paste into Make.com, because multiline text will not work in the module.

Slack's API can change, so if the method stops working, search for the Slack API docs and look at the web API conversation and canvas methods.

Can you update the canvas later?

You could put all the content into the first call and skip the second, but keeping them separate has a benefit. If you store the Slack channel ID and canvas ID in your project management database, a later automation can edit the canvas whenever something changes, for example project status or a list of call recordings.

The most useful upgrade is to connect this to your full onboarding process: create the Google Drive folder, create the Slack channel, book the call, send the onboarding email and invite team members, then create the canvas as one step in that chain.