Fix wire-validation attribution bugs, extend schema erratum to 2025-06-18 - #421
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… 2025-06-18 Follow-ups from the #399 review: - Stateless mock: validate error replies with a placeholder id so the JSON-RPC-mandated id:null is not recorded as a harness violation, and skip inbound validation when express left the body unparsed (wrong or missing Content-Type) — both were false positives blamed on the wrong party. Same unparsed-body guard in the stateful mock. - Stateful mock: validate client traffic against the protocol version the client declares via MCP-Protocol-Version, falling back to 2025-03-26 when the header is absent (it only exists from 2025-06-18, whose spec says to assume 2025-03-26), instead of always using the run version. - sdk-client: validate batches once as a whole array instead of also per element, which double-recorded every violation. - Make specVersion required on connectToServer/connectStateful/ createServerStateful; add isSpecVersion to types.ts. - Extend the NumberSchema erratum to 2025-06-18 (same generator bug on minimum/maximum, modelcontextprotocol#3139) and add a tripwire test that forces erratum deletion once the schemas are re-vendored. - Document the wire-schema-valid / wire-schema-harness-error check IDs in the README.
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…ation Reuses the canonical spec-version list from #421 instead of keeping a separate copy; SPEC_VERSION_TIMELINE is now exported so the validation message can enumerate the valid keys.
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Follow-ups from the #399 review (deferred there to keep the merge unblocked):
Attribution false positives fixed
id: nullerror replies no longer record a spuriouswire-schema-harness-error(validated with a placeholder id, mirroringwithNullIdCarveOut).undefined.MCP-Protocol-Version(falling back to 2025-03-26 when absent, per the 2025-06-18 spec) instead of the CLI-resolved run version, so clients that legitimately negotiate a different version (README permits this) are not false-flagged.Hardening
specVersionis now required onconnectToServer/connectStateful/createServerStateful— omitting it silently validated againstLATEST_SPEC_VERSION.isSpecVersionguard intypes.tsreplaces an inline version-list copy.Erratum
minimum/maximum(spec fix: modelcontextprotocol#3139, also extended).Docs
wire-schema-validandwire-schema-harness-errorcheck IDs, including that harness errors indicate suite bugs and that scenarios with no instrumented traffic (Wire-schema validation does not see raw-HTTP / inline-mock scenario traffic #418) emit neither check.474/474 tests (+12 new covering each fixed behavior and the no-header fallback); verified at the CLI that an id-less client message is flagged as an implementation violation with no harness-error check emitted.