Publish an artifact

Create HTML, Markdown, and JSX artifacts from the CLI, REST API, or MCP.

Publishing creates an artifact and its first immutable version. Updating it later appends more versions without changing the earlier snapshots.

Pick a surface

Use whichever surface matches who (or what) is publishing:

You are…	Use
A human in the browser	Web dashboard
A local coding agent	CLI
A backend service or CI job	REST API with an API key
An MCP-capable agent	MCP tools

Create an artifact

The fastest path from a local file to a durable URL is the CLI’s push. The REST and MCP equivalents take the same fields explicitly.

CLI

artifacts push --owner alice --project-slug default --file ./report.md

What push infers

push is built for speed — it fills in everything it can from the file:

• Type from the file extension: .md, .markdown, .html, .htm, .jsx, .tsx.
• Title from the Markdown heading, or the file name.
• Slug from the title.
• Access as public view, private edit.

Override any of it when you need to:

artifacts push \
  --owner alice \
  --project-slug default \
  --file ./prototype.tsx \
  --type jsx \
  --title "Prototype v1" \
  --slug prototype-v1 \
  --private

Use --ensure when an agent should reuse an existing artifact instead of failing on a slug conflict:

artifacts push --owner alice --project-slug default --file ./report.md --ensure

REST fields

For POST /api/artifacts, these fields are required: projectSlug, slug, type, title, content, and access. ownerUsername is optional — when omitted, the API infers the owner from the authenticated credential (the signed-in user, or the account an API key / agent token was issued for). Pass it only to publish into another account you can access. The description and changelog fields are also optional.

Publish into a workspace

When you already have a workspace ID, post to the workspace route instead. The body is the same, minus ownerUsername (the workspace is already selected):

POST /api/workspaces/:workspaceId/artifacts

Update an artifact

Appending a version needs only the artifact ID and new content.

CLI

artifacts artifact update \
  --artifact-id ARTIFACT_ID \
  --json '{"content":"# Launch review\n\nUpdated after QA.","changelog":"QA edits"}'

For concurrent writers, include expectedLatestVersion in REST or MCP requests. If the head has moved on, the API returns a conflict instead of silently overwriting another actor’s work.

Check a slug before you publish

Avoid surprises by checking availability and previewing the final URL first:

artifacts artifact slug-availability \
  --owner alice \
  --project-slug default \
  --slug launch-review

artifacts artifact url-preview \
  --owner alice \
  --project-slug default \
  --slug launch-review