v1.6.0

Changed

• _meta.ui.domain is now a host-supplied verbatim value; server-side
  auto-derivation is retired. (Behaviour change — minor.) The MCP Apps spec
  makes domain host-dependent — the host mints the dedicated iframe origin
  and documents its format; a server copies it verbatim or leaves it empty.
  App.Domain is emitted on resources/read byte-for-byte; Dockyard no
  longer synthesises Claude's {hash}.claudemcpcontent.com subdomain (which a
  local connector rejects). What changes for you: a project that set
  HostProfile: "claude" + Domain previously got a derived
  claudemcpcontent.com origin and now gets its Domain verbatim — set Domain
  to the exact origin your host documents for a verified remote deployment, or
  leave it empty for the host's default per-conversation origin. App.HostProfile
  and App.ServerURL are deprecated (retained, ignored for derivation); the
  pluggable host-profile seam stays for a future host-blessed transform. The
  default scaffold and templates set no Domain, so they are unaffected. (D-176)

• A stdio-only server that sets a Domain now warns at startup. A dedicated
  origin is honoured only on a remote connector; a local (stdio) connector
  ignores it. ServeStdio logs a loud slog.Warn naming the App;
  HTTPHandler does not. (D-176)

• The product templates scaffold the html-style
  ui://<server>/<app>/index.html resource URI. This matches the reference MCP
  Apps SDK convention. The framework treats the ui:// URI as an opaque string,
  so this is a convention + docs change only — an existing project's
  ui://<server>/<app> URI keeps working. (D-178)

Added

• A server-level opt-in to additionally emit the deprecated flat tool-UI
  _meta key. server.Options{EmitLegacyToolUIMeta: true} makes every
  UI-bearing tool registered through the runtime/tool builder carry the
  deprecated flat key alongside the canonical nested _meta.ui.resourceUri, for
  a host that still reads the flat form. The default (off) is unchanged
  RFC-compliant nested-only output; the 2026-01-26 spec marks the flat form
  deprecated, so Dockyard never emits it by default. (D-177)

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Commits

Added

• apps: v1.6 wave A — MCP Apps spec-alignment (verbatim domain, opt-in flat key, html-style URI)