Stacktree vs ShareDuo: which to use in 2026.

Two different publish models

The core split is who does the publishing. ShareDuo is paste-first: you take the HTML of a finished Claude artifact, paste or upload it on shareduo.com, and a link comes back in seconds. No account is required to upload or to view. It supports the full range of static artifacts Claude emits: HTML, React, SVG, Mermaid diagrams, small games, calculators, and dashboards. The product is shaped around the moment a person has something finished and wants to hand it to someone.

Stacktree is agent-first: the publisher is a program, not a person. An AI agent calls publish_html({ file }) over the MCP endpoint at api.stacktr.ee/mcp and gets back an unguessable URL. The link itself is the credential. There is no browser step, no paste, no upload dialog, because the agent never leaves its loop to publish.

Where ShareDuo genuinely wins

• Fastest human paste-to-link. If you already have an artifact open and want a link to send right now, pasting into ShareDuo and getting a URL in seconds is hard to beat. No tool wiring, no MCP setup.
• No account to start. The free tier needs no signup to upload or to view, which lowers the barrier for a one-off share to someone outside any account system.
• Built-in analytics on Plus. Its Plus tier adds Google Analytics and Google Search Console verification, so you can measure views and, if you want, let the link be discoverable in search.
• Deep content focus on Claude artifacts. ShareDuo is purpose-built for the share-a-Claude-artifact job and documents it thoroughly, which is exactly the right surface for that one task.

Where Stacktree genuinely wins

• Agent publishes directly. publish_html, update_site, and delete_site are first-class MCP tools. The agent publishes, revises, and removes a site without a person in the loop.
• Replace in place. One stable URL per artifact. Calling update_site with the same slug updates the content behind a link you already shared, so there is no new link to redistribute each iteration.
• Layered gating per link. Beyond the unguessable URL, each site can carry an optional password, an email-domain gate verified by magic link, or a per-link expiry, set as separate tool calls.
• Flat workspace pricing. $0, $8, and $19 tiers, never per-seat, plus pay-to-provision unlocks an agent can buy itself (make a link permanent, add a custom domain, raise limits).

Privacy and gating compared

Both products keep links unlisted rather than broadcast. ShareDuo states that nothing is indexed or listed publicly by default and lets you add a password to restrict access further. Stacktree goes private-by-default by construction: every URL is unguessable, so the link is the access token, and there is nothing to index because there is no public listing or directory. The practical difference is the depth of the gate. ShareDuo offers a password; Stacktree adds an email-domain gate (only addresses on a domain you name can open the link, verified by magic link) and a per-link expiry on top of the password option, and the agent sets each one itself.

Pricing models compared

As of 2026 ShareDuo runs an always-free tier with no account required, where links expire after 1 hour, 1 day, or 7 days, plus a Plus tier around $4.99 per month that adds 30-day and permanent links, Google Analytics, and Google Search Console verification. Confirm the current numbers on the ShareDuo pricing page before quoting, since tiers move. Stacktree uses flat workspace pricing: $0 Free (a permanent free tier), $8 Pro, and $19 Agent, never per-seat. On top of that, an agent can pay for one-off unlocks with x402: make a link permanent for $1 once, add a custom domain for $5 per 30 days, or raise limits for $5 per 30 days. The two are not priced to compete directly; one is a low monthly add-on for a human, the other a workspace plan with agent-paid extras.

Side by side

Who each is for

If you are a person who has a finished artifact in the Claude UI and you want the shortest possible path to a link you can send, with no account and a short default expiry, ShareDuo is squarely built for that and does it well. The free tier, the optional password, and the Plus analytics cover the human share-it-now job cleanly.

If the author is an agent rather than a person, the job is different. An agent in a loop produces HTML repeatedly: a spec, a status report, a custom one-off dashboard, a draft it will revise three more times. You want each output published the moment it exists, private until you choose otherwise, and updated behind one stable link rather than scattered across a new URL per run. Stacktree is built around that single primitive. The agent calls publish_html, gets an unguessable URL, calls update_site to revise it in place, and calls delete_site to burn it when done. It is deliberately narrow: static HTML only, no in-browser editor, no build pipeline. Skills for popular agents live at /skills, and the publish primitive is documented at /mcp-publish-html.