* feat(everything-server): serve resources and caching hints on the stateless draft path
The stateless (SEP-2575) request path now answers resources/list,
resources/templates/list and resources/read — including the SEP-2164
-32602 + data.uri error for unknown URIs — and includes the SEP-2549
ttlMs/cacheScope hints on its cacheable list results, matching what the
draft-spec scenarios exercise.
* feat: make the harness's own draft-spec traffic conformant
Fixes the class of issues where a strictly-conformant SDK rejects the
harness's requests for reasons unrelated to the behaviour under test
(#311, #312, #315).
- add a shared stateless draft request helper (draft-client.ts) that puts
the cross-cutting SEP-2243 headers (Mcp-Method, Mcp-Name,
MCP-Protocol-Version, Accept) and SEP-2575 _meta (protocolVersion,
clientInfo, clientCapabilities) on every request, with overrides for
negative cases and the SHOULD-level retry on
UnsupportedProtocolVersionError
- migrate the draft scenarios onto it: the SEP-2322 helpers and
server-stateless now send Mcp-Method/Mcp-Name (#312); the SEP-2243
server scenarios drop the legacy initialize handshake and carry _meta on
every raw request (#311); caching and sep-2164-resource-not-found are
stateless DRAFT-2026-v1 requests instead of an SDK 2025-11-25 session
(#315)
- add a draft self-conformance gate (draft-self-conformance.test.ts) that
points the harness's own draft drivers at the existing client-testing
judge scenarios (request-metadata, http-standard-headers) and requires
zero failures or warnings
- align the request-metadata mock's unsupported-version rejection with the
draft schema (-32004) and teach the everything-client to recognize it
- rewrite the SEP-2549/SEP-2164 negative example servers as stateless
draft servers so they keep exercising the violation, not the transport
* refactor: rename the stateless request helpers and harden them per review
- rename draft-client.ts to stateless-client.ts and name the helpers by
feature (sendStatelessRequest, buildStandardHeaders, buildRequestMeta,
withRequestMeta, CONFORMANCE_CLIENT_INFO); 'draft' now only appears in
DRAFT_PROTOCOL_VERSION, the one name that tracks the moving target
- retry only genuine UnsupportedProtocolVersionError rejections (-32004,
tolerating -32001/-32602) and only with recognized versions; record the
retry on the response
- parse text/event-stream responses incrementally and resolve on the
matching event instead of blocking until the timeout
- keep the MCP-Protocol-Version header and _meta protocolVersion in sync
when the version is overridden via meta overrides
- make server-stateless's sendRpc SSE-tolerant
- emit explicit setup failures in the SEP-2243 server scenarios when the
tools/list discovery fails instead of misleading per-case results
- latch the worst status per check in the request-metadata judge so an
early violation cannot be masked by a later conformant request
- rename the gate to harness-traffic-conformance.test.ts and derive its
driver list from the draft suite with documented per-judge exclusions
(35 pairings)
- everything-server: advertise resources in stateless server/discover and
use -32004 for unsupported protocol version
- add unit tests for the helper (retry guard, SSE handling, header/_meta
version sync, default headers)
* refactor: slim the stateless client helper for the initial merge
* chore: additional server conformance tests for SEP-2575
* fix(sep-2575): use the spec's notifications filter object in subscriptions/listen
The scenario sent params.subscriptions: [{type: 'tools/list-changed'}], a
shape that does not exist in the SEP. SubscriptionsListenRequestParams
requires params.notifications: {toolsListChanged?, promptsListChanged?, ...}
(see schema.ts SubscriptionFilter and the canonical
SubscriptionsListenRequest example). A compliant server would either reject
the old request as invalid params or treat it as subscribing to nothing,
failing the ack/list-changed checks.
Also makes the everything-server's acknowledgment echo the agreed
notifications filter, as the SubscriptionsAcknowledgedNotification schema
requires.
* fix(sep-2575): match the spec's notifications/*/list_changed method names
The list-changed checks and the everything-server used
notifications/tools/list-changed (hyphen); the spec's method is
notifications/tools/list_changed (underscore) per ToolListChangedNotification
/ PromptListChangedNotification in schema.ts. With the hyphen form the
notification-filter check cannot catch a real leak, and the list-changed
checks fail a server that emits the correct name.
Also drops the f.params.toolsListChanged === true fallback match: that field
is the subscriptions/listen request filter, not a notification parameter, so
it never appears on a compliant server's notification.
* fix(sep-2575): keep collected frames when the listen stream read times out
listenToStream aborts the fetch after timeoutMs. If the abort fired while
blocked in reader.read(), the rejection propagated to the outer catch and the
helper returned [] — discarding every frame already received. A compliant
server holds a subscriptions/listen stream open indefinitely, so the timeout
is the *normal* way these reads end; previously every subscription check
would report a false 'no frames received' FAILURE against such a server.
The current everything-server only avoided this by res.end()ing immediately
after the ack.
* fix(sep-2575): open the listen stream before triggering list mutations
The notification-filter and list-changed checks fired the mutation trigger
*before* opening the subscriptions/listen stream. A compliant server only
delivers list-changed notifications to streams that are open at the time of
the change, so the SHOULD checks would fail any server that does not replay
past changes to new subscribers, and the filter check could never observe a
real leak.
listenToStream now takes an onFirstFrame hook; the three trigger-based
checks open the stream, wait for the acknowledgment, then fire the mutation
on a separate connection and keep reading.
The everything-server now keeps subscriptions/listen streams open, registers
them with their filters, and fans the list_changed notification out to open
streams when a trigger tool runs - instead of unconditionally emitting a
list-changed frame on every stream open (which itself violated the
notification-filter requirement in spirit: it announced a change when
nothing had changed).
* fix(sep-2575): check the subscription id on every listen-stream notification
server-tags-subscription-id only inspected the acknowledgment frame, so a
server that tags the ack but omits io.modelcontextprotocol/subscriptionId
from subsequent notifications passed. The check now triggers a tool-list
change once the stream is acknowledged and asserts every notification frame
on the stream carries the id in params._meta.
Also drops the f.body.method / f.params.method fallbacks when resolving a
frame's method - those shapes don't exist in JSON-RPC and only masked
malformed frames.
* fix(sep-2575): report WARNING, not FAILURE, for the SHOULD-level list-changed checks
The spec text behind server-sends-{tools,prompts}-list-changed-on-subscription
is a SHOULD ('servers that declared the listChanged capability SHOULD send a
notification...'). Severity follows the spec keyword: MUST -> FAILURE,
SHOULD -> WARNING. runCheck now accepts a warning flag and the two
list-changed checks use it on their failure paths.
* fix(sep-2575): skip stream checks when the diagnostic tool is not exposed
http-server-no-independent-requests-on-stream and
server-no-log-without-loglevel reported SUCCESS when the server rejected the
tools/call outright (e.g. test_streaming_elicitation / test_logging_tool do
not exist): a single error frame contains no independent request and no log
notification, so the check passed without exercising anything. The sibling
list-changed checks already SKIP when their trigger tool is missing; these
now do the same.
* chore(sep-2575): exclude the four unobservable server requirements from traceability
Marks the section-C rows of #296 as excluded rather than untested:
no-prior-context, no-connection-reuse-required, disconnect-is-cancel and
stops-on-cancel describe internal server state that a black-box harness
cannot observe on the wire. With these excluded and the part-B checks landed,
every testable server-side SEP-2575 requirement is covered; the remaining
untested rows are all client-side and blocked on a SEP-2575-aware reference
client.
---------
Co-authored-by: Paul Carleton <paulc@anthropic.com>
* feat: add server conformance tests for SEP-2575
* refactor and add new checks
* Fix stateless scenario source field and report SKIPPED for inapplicable capability checks
- Add the required `source` field (DRAFT) so the scenario typechecks and is
selectable via --spec-version. Without it the class did not satisfy the
ClientScenario interface and s.source was dereferenced by the spec-version
filter at list time.
- Teach runCheck about a SKIPPED status and use it for the two client-capability
checks when the server does not return -32003, instead of reporting a green
PASS for a requirement that was never exercised.
* Remove unimplemented placeholder checks from stateless server scenario
The subscriptions/listen, statelessness-invariant, list-changed and
disconnect-is-cancel checks emitted SUCCESS without probing the server,
which inflated coverage in the traceability report. Drop them until they
have real assertions; the corresponding rows remain declared in
src/seps/sep-2575.yaml so traceability shows them as not-yet-covered.
Also fix the checkErrorId helper to push under the
sep-2575-http-server-error-jsonrpc-id slug so its failure path actually
short-circuits the aggregate SUCCESS check at the end of the scenario.
---------
Co-authored-by: Paul Carleton <paulc@anthropic.com>
Paul Carleton
Yuan Teoh