Only the top modal owned the focus trap, but every lower `Modal.Content`
remained an exposed `aria-modal` dialog with reachable controls and a live
iframe — so browse navigation could land in a dialog that is visually covered
and that itself claims the rest of the page is inert.
Non-top contents are now `inert`: out of the accessibility tree and out of
focus order, without unmounting, so each app keeps its bridge and its handshake
and is live the moment it becomes top.
Signed-off-by: cliffhall <cliff@futurescale.com>
Two of the three findings; the third is answered in the PR thread.
**A replaced client could still enqueue.** The one-shot sweep only rejected what
was already queued, but the outgoing `InspectorClient` disconnects
asynchronously and can enqueue during its own teardown — and that late entry
would be rendered by a factory bound to the REPLACEMENT client, reading its
resource and answering through a different server. Requests now belong to a
session: each constructed client gets one, closing it rejects that session's
entries AND refuses anything it queues afterwards, and another session's
entries are untouched.
**The advertisement no longer has to guess.** Whether a sandbox exists is only
known once `/api/config` resolves, and the answer is baked into the client at
construction — guessing "available" over-claims, guessing "unavailable" strands
the whole session on the native form despite having a sandbox. The connect path
now awaits that fetch (already in flight since mount, so no human ever waits;
it only orders a deep-link auto-connect racing the same page load), after which
an absent `sandboxUrl` means confirmed-absent.
Signed-off-by: cliffhall <cliff@futurescale.com>
**The task-augmented inbound branch bypassed the routing.** A server→client
`elicitation/create` carrying `params.task` answers immediately with a
`CreateTaskResult` and settles the TASK when the user answers, so it cannot
ride `enqueuePendingElicitation` — and it was therefore never offered to an
app, even with a valid `_meta.ui.resourceUri`. It now makes the same attempt,
completing the task with the app's result and falling back to the native queue
otherwise; an abort fails the task rather than reopening it natively. The two
task-settling closures are extracted so both answer routes settle it
identically.
**The web client advertised the capability without a sandbox.**
`useInitialConfig` leaves `sandboxUrl` undefined while `/api/config` is in
flight and when the sandbox controller could not start, but the renderer was
supplied unconditionally — so the client claimed it could host an app in
exactly the window where it could not. The option is now gated on a resolved
sandbox URL: such a connection behaves like the CLI/TUI, native queue and no
claim made.
**Concurrent modals each owned the keyboard.** Every open `Modal.Root`
installed its own focus trap, Escape handler and overlay, so the traps fought
and one Escape could dismiss more than one pending request. Only the topmost
owns them now; the rest stay mounted, keeping their bridges and handshakes,
but inert to the keyboard.
Signed-off-by: cliffhall <cliff@futurescale.com>
Eight findings from the Copilot review, all accepted.
Ownership across connections was the substantive one, in three parts. A
mid-session transport close reaches teardown only through
`clearAndAnnouncePendingPeerRequests`, whose emptiness check looked at the
native queues alone — so a lone app elicitation survived a dropped connection
with its modal still open; the check now counts the active set too. The web
bridge factory resolves its client at call time, so an entry queued by a
replaced `InspectorClient` could rebuild against the *next* one and answer
through a different server; the host now drops every entry synchronously on
the swap (`AppElicitationController.failAll`) rather than racing core's
awaited teardown. And the request id was only monotonic within one client, so
each replacement client's first request was `app-elicitation-1` — settling
that id could resolve the wrong server's request. It now carries a
per-instance prefix.
Result validation now parses the whole value with `ElicitResultSchema` before
the requested-schema check, instead of inspecting `action` by hand: a
`{ action: "decline", content: { x: {} } }` used to pass, though the standard
result permits only primitives and string arrays in `content`.
The dialog's accessible name now includes the request id and the prompt — two
concurrent elicitations can be for the same app URI, and the previous name
made those indistinguishable, which is what the comment beside it claimed to
prevent.
`observeAppCapabilities` takes a minimal structural `onmessage` contract
(generic over the message type, since a handler typed for a narrower message
is not assignable to one typed for `unknown`), removing the double cast at the
call site.
`smoke:web:elicit` now fails on an uncaught page error after a successful
drive, and captures the async half of that class off the console channel, as
its two sibling smokes do — it could otherwise print OK over a broken bundle.
Adds the tests each fix needs, including the two the review asked for
directly: that `advertiseElicitation` reaches the `AppBridge` constructor, and
that it is absent by default.
Signed-off-by: cliffhall <cliff@futurescale.com>
Let a server hand a form `elicitation/create` to an MCP App and return the
app's ordinary `ElicitResult`, with the native elicitation form as the
fallback on every failure.
No second extension, no custom method, and no custom result shape: the only
new wire surface is a nested `elicitation` flag on the existing
`io.modelcontextprotocol/ui` extension on each side, plus
`_meta.ui.resourceUri` on the request. App rendering is selected only when
all four gates hold — client `elicitation.form`, client MCP Apps MIME type,
the nested `elicitation` setting on BOTH peers, and a valid absolute `ui://`
URI on the request.
Only the web client advertises the nested client-side setting, and only
because it has a sandbox renderer: supplying
`InspectorClientOptions.appElicitation` is what opts a client in, so CLI and
TUI keep advertising the MIME type without ever claiming they can resolve an
elicitation through an app.
Routing lives in the one funnel both entry points already use
(`enqueuePendingElicitation`), so the inbound handler and the MRTR driver
cannot diverge. Ownership is request-scoped — a per-request id keys the
renderer, iframe and bridge — so two concurrent elicitations can never
resolve through each other's bridges. An explicit `decline`/`cancel` is a
completed elicitation and goes back to the server; everything else (absent or
malformed metadata, resource/sandbox/bridge failure, an app with no
elicitation capability, a timeout, an invalid result or one that fails the
requested schema) falls back.
The Inspector speaks the ext-apps#733 / SEP-3118 wire protocol but cannot yet
consume its helpers — the released `@modelcontextprotocol/ext-apps` (1.7.5)
predates that PR. `core/mcp/appElicitation.ts` and
`AppRenderer/requestAppElicitation.ts` mirror it exactly and are marked for
deletion once a release containing it ships. One consequence needed its own
seam: ext-apps 1.7.5 parses the view's `ui/initialize` through a schema that
strips `elicitation`, so an app that correctly advertises it would look like
one that did not, silently turning every negotiated elicitation into a
fallback. `AppRenderer/appCapabilities.ts` records the raw frame instead, and
prefers the bridge's own value once it carries the key.
`AppRenderer` now takes an `AppRenderSource` union rather than a `Tool`, so
the same renderer and bridge factory serve an App tool and an elicitation
without either faking the other's shape.
Adds the public fixture (`app_choose_option` + a self-contained
`ui://demo/choose-option.html` app covering accept/decline/cancel), its two
showcase configs, and `smoke:web:elicit`, which drives the negotiated path
end to end in headless Chromium and then the same tool against a server that
never advertised the capability, asserting the native form takes it.
Closes#1854
Signed-off-by: cliffhall <cliff@futurescale.com>
