Cowork writes the proposal. Now send it.

Where the workflow stops

Claude for Small Business launched on 15 September 2026 as a Cowork plugin with 43 ready-to-run workflows. One of them, Proposal builder, turns a voice memo, a photo or an RFP into a branded proposal priced from your past jobs. It is a genuinely good piece of automation, and it ends exactly where every one of the 43 ends: with a document, and a deliberate pause. Nothing sends until you approve it.

That pause is correct. What is not correct is what most people do next, which is attach the file to an email. The client downloads it, opens it from their file system, reads it in whatever application claims the extension, and you learn nothing about whether they got past page one. If the file is a large self-contained HTML page, it may not arrive at all: Gmail caps attachments at 25 MB, and mail filters treat HTML attachments with justified suspicion.

A proposal is a document whose entire job is to be opened, read and acted on. Sending it in the one format that resists all three is a strange way to end a good workflow.

The send step, in seven moves

1. Run the workflow. Proposal builder, or whichever one applies. Review what it drafted and approve it. This is the part Cowork already does well.
2. Save the output as a page. Ask for the deliverable as one self-contained HTML file, or export the document it produced to HTML. One file, styles and images inside it, nothing to unzip.
3. Publish it. Drag the file onto the Stacktree dashboard, or let Claude do it: Cowork speaks MCP, so the publish_html tool publishes the file it just wrote and hands back the URL in the same session. Either way you get an unguessable link that appears in no listing and no search index.
4. Add a passcode. One shared secret you tell the client, so a forwarded link alone opens nothing. If the proposal is going to several people at one company, restrict it to their email domain instead and let anyone at that domain in after a one-time magic link.
5. Send the link. Paste the URL into the email or the thread you were already writing. The client clicks and reads a page, on a phone in a taxi if that is where they are.
6. See when it is opened. Opens and last-read on Solo, plus the reactions and notes the client leaves on the page itself. Studio adds time on page, scroll depth and a dwell heatmap, so you can tell whether they reached the pricing section before they replied.
7. Update in place after the call. They asked for a different scope. Re-run the workflow, publish over the same site, and the link in their inbox now shows the revised proposal. No resend, no version two in the subject line, no risk of the wrong number being the one they sign.

Why a link beats an attachment for a proposal

• It opens. On any device, in any browser, with no application and no download prompt.
• It is current. The version they see is the version you published most recently, so revisions do not fork.
• It is private on purpose. Unguessable by default, passcode or company-domain gated when you want it, expiring on a date you choose.
• It tells you something. Opened, when, how far read. A proposal opened three times the morning before a decision is useful information.
• It looks like your work. Put it on your own domain, so the client reads it at proposals.yourfirm.com rather than at a vendor URL, and paid plans render no badge.

Let Claude do the publishing

If you would rather not touch a file at all, connect Stacktree as an MCP connector and stay inside Cowork. The plugin package is open at github.com/stevysmith/stacktree-skill, carrying the publish skill, the job-shaped skills for client deliverables and reports, and the Stacktree MCP server. Cowork accepts a Git repository as a marketplace, so the repository URL goes straight into Customize, Plugins, Add marketplace. The plugin mechanics in full are on Claude Cowork plugins and skills.

Once it is connected, the end of a workflow becomes one more approved step: Claude publishes the proposal, sets the passcode, and gives you the link to paste. The same server works from Claude Code and any other MCP client, which matters if half your work comes out of a terminal and half out of Cowork.

Also read

If you are starting the proposal rather than finishing one, the business proposal template is the shape to hand Cowork: what a priced proposal needs on the page, in the order a client reads it. For the wider handoff, sharing deliverables with clients covers reports, dashboards and demos behind the same gates, and sharing an HTML file with a client is the format-level version of this page.