Every state-subscription hook in core/react/ seeded local React state from
its store prop and re-synced it inside a useEffect. That shape paints one
frame of the previous store's data when the prop changes (switching
servers), and loses any event dispatched between the render that took the
snapshot and the effect that attached the listener.
Convert all 16 to useSyncExternalStore through a new shared
useStoreSnapshot, following useManagedListError (#1954).
useSyncExternalStore needs a referentially stable snapshot, and these
getters hand back a defensive copy, so TypedEventTarget now keeps a
per-event-type dispatch counter (getEventRevision) that the snapshot is
cached against. A contents comparison would not do: MessageLogState folds
a response into its request entry by mutating that entry in place, which a
shallow compare reports as unchanged. The bump lives on the dispatchEvent
override so no dispatch — including a hand-rolled CustomEvent — can bypass
it.
useInspectorClient is included though the issue did not list it; its nine
subscribed slices made the stale frame most visible. Its lastError stays
useState (accumulated from events, no getter to read back) but resets on
client swap during render rather than in an effect.
The settings-draft and async fetch hooks are deliberately untouched: the
former hold genuinely local editable state, the latter are I/O rather than
store subscriptions.
Also answers the issue's open question. react-hooks/set-state-in-effect
never fired here because eslint-plugin-react-hooks has never linted
core/react/ at all — it is a clients/web devDependency and the root config
loads no React plugin. Corrected the config comment that gave "no JSX" as
the reason; the gap itself is #2192, measured at 15 findings, none of them
in the hooks converted here.
Closes#1955
Signed-off-by: cliffhall <cliff@futurescale.com>
- Run Prettier on the 60 core/ files this PR touched — the deterministic
import rewrite had collapsed multi-line imports and left throws unwrapped;
core/ is in no format gate so it slipped past CI. Now Prettier-clean.
- Default-path output-schema violation now throws
ProtocolError(ProtocolErrorCode.InvalidParams, …) instead of a bare Error,
matching the prior v1 contract (SDK threw a typed McpError with a code) so
downstream `instanceof`/`.code` branching keeps working.
- Document the "assumes serial construction" invariant on pollTaskToolCall's
progress-subscription revival (the `_progressHandlers` new-key heuristic).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Migrate all three clients + core + test-servers from
@modelcontextprotocol/sdk@1.29 to SDK v2 (2.0.0-beta.4), keeping behavior
identical against legacy (2025-11-25) servers. Foundation for the SDK V2 +
New Spec stack.
Packages
- Split @modelcontextprotocol/sdk -> @modelcontextprotocol/client (Client,
transports, OAuth, error taxonomy, protocol types) + core (Zod schemas);
stdio -> client/stdio, Ajv -> client/validators/ajv. Test-servers ->
@modelcontextprotocol/server (+ server-legacy/sse). Deterministic import
rewrite (schemas -> core, everything else -> client); the codemod misroutes
client code to /server so it was not used for path routing.
- new Client(..., { versionNegotiation: { mode: 'legacy' } }) — nothing
2026-era goes on the wire.
Runtime (core/mcp/inspectorClient.ts)
- Error taxonomy: McpError -> ProtocolError, ErrorCode -> ProtocolErrorCode;
RequestTimeout -> SdkError/SdkErrorCode.
- Handlers take method strings; task methods (tasks/*, notifications/tasks/*)
use the 3-arg custom form (excluded from v2's spec-method set).
- Legacy tasks kept working (per project requirement): requestor tasks re-
implemented over raw client.request + explicit deprecated schemas;
experimental.tasks.callToolStream replaced by a local pollTaskToolCall
async generator (with _progressHandlers revival so task-execution progress
still reaches the caller). Receiver (server-initiated) tasks: the v2 Client
validates a sampling/elicit handler result and rejects the legacy { task }
response with -32602 — installReceiverTaskResponseBypass swaps the wrapped
entry in the private _requestHandlers map for the task-augmented branch so
{ task } reaches the wire (fixes server-initiated sampling-via-task).
- Pagination: list verbs use raw client.request({method}, List*ResultSchema)
for single-page behavior (v2's client.listX() auto-aggregate all pages).
Web / auth / apps
- Rename local JsonSchemaType -> InspectorFormSchema + add toFormSchema()
structural narrowing at the SDK-schema -> form boundary.
- ext-apps still peers on SDK v1: one compat boundary with documented casts
(remove when ext-apps#702 lands a v2 peer).
- OAuth provider saveClientInformation reconciled with v2's
OAuthClientInformationContext; InvalidClientMetadataError re-homed as a
local class (server-legacy/auth is not browser-safe).
- vitest.shared.mts dedupes @modelcontextprotocol/client+core to one copy so
vi.mock intercepts the SUT's import.
Accepted v2 behavior changes (per #1624 / spec §9.2): unknown-tool call
rejects with -32602; cancellation is stream-abort (no guaranteed
notifications/cancelled frame); output-schema strictness restored via the
Inspector's own Ajv check on the default path.
npm run ci green: validate (web 3087 / cli 212 / tui 274 / launcher 5),
coverage (>=90 per-file, all clients), smoke (launcher/cli/web), storybook
(410).
Closes#1624
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(core): port v1.5 hook layer (useInspectorClient + useManaged*/usePaged* + log hooks)
Wholesale port of v1.5's React hook layer and the EventTarget-based state machinery the hooks subscribe to (#1243). Hooks decouple from the concrete InspectorClient via a new `InspectorClientProtocol` interface so this layer can land before the runtime class is ported.
Added under `core/`:
- `core/react/` — useInspectorClient + 5 useManaged* + 5 usePaged* + 3 log hooks
- `core/mcp/state/` — 5 managed*State + 5 paged*State + messageLogState + stderrLogState + fetchRequestLogState
- `core/mcp/inspectorClientProtocol.ts`, `inspectorClientEventTarget.ts`, `typedEventTarget.ts`, `samplingCreateMessage.ts`, `sessionStorage.ts`
- v2-only wrapper types in `core/mcp/types.ts`: InspectorUrlElicitRequest, InspectorPendingRequest, InspectorRequestHistoryItem
Tests live under `clients/web/src/test/core/` (28 new test files, 264 new tests). Test fake: `core/mcp/__tests__/fakeInspectorClient.ts`.
Build wiring:
- `vite.config.ts`: dedupe react/react-dom so core/ files resolve them via clients/web/node_modules.
- `tsconfig.app.json` / `tsconfig.test.json`: paths map react/react-dom/vitest to clients/web/node_modules so `tsc -b` resolves bare imports from core/ source files (which sit above the package's node_modules). Exclude core/__tests__ from app config; include in test config.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* review: address PR #1300 review findings
Bugs:
- fetchRequestLogState: add .catch() on sessionStorage.loadSession so a corrupt
or unreadable session doesn't surface as an unhandled rejection (matches the
saveSession swallow pattern).
- messageLogState: sync pendingRequestEntries when clearMessages() evicts a
pending request entry, so a later response with the same id falls through
to the append branch instead of mutating an unreachable map entry. Add tests
for both predicate and no-predicate paths.
Cleanups:
- Extract mergeTaskIntoList helper to core/mcp/state/mergeTaskIntoList.ts so
managed/paged RequestorTasks state classes share one definition.
- Add a one-line JSDoc note on each PagedTools/Prompts/Resources/Templates
state explaining why they deliberately do not subscribe to *ListChanged
(cursor invalidation mid-pagination).
- Document on useInspectorClient that appRendererClient is read lazily on
every render and is not subscribed (changes once at connect time).
Carry-overs from v1.5 deliberately left for the follow-up InspectorClient
runtime port:
- Refresh/status-change race in Managed*State.refresh() (status check is only
at entry; a disconnect during await can re-clear before refresh resumes).
- nextCursor exposure asymmetry across usePaged* (only usePagedRequestorTasks
surfaces it via state field; others return it from loadPage() only).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
cliffhall