Round 16 reported no inline comments and three suppressed findings, all
valid:
- `getSkillsExtension` treated a non-object extension value (`false`,
`"skills"`) as a declaration. SEP-2133 declares an extension as an
object of sub-options, so a primitive is not one — now rejected,
matching `appElicitation.ts`.
- The `onGetSkill` prop doc claimed the two responses "must agree" and
that a difference means a broken server, contradicting the
implementation, which reports a difference as a finding rather than a
fault. Reworded to what the code does.
- No real-transport test exercised the fixture's `skills/*` handlers.
Added `src/test/integration/mcp/inspectorClient-skills.test.ts`,
parameterized over both protocol eras: capability advertisement, the
paged `skills/list` walk (direct and through `ManagedSkillsState`),
`skills/get`, the `-32602` for an unknown URI, `resources/read` of a
skill file, and delegation of an ordinary resource through the
fixture's `resources/read` wrapper.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
The review finally quoted the normative text, which is what I asked for
across five rounds before declining: SEP-2640's `skills/list` section says
"In protocol versions 2026-07-28 and later, the result also carries …
`ttlMs` and `cacheScope`." So the era-aware validation is in.
- skillsSchemas: `ModernListSkillsResultSchema` = the page plus the base
list envelope, with field shapes mirroring `ModernResultEnvelopeSchema`
in `listSalvage.ts` so this repo's two statements of a modern envelope
cannot drift. `InspectorClient.listSkills` picks it from the negotiated
era; the legacy shape stays permissive, because those are 2026-era
attributes a legacy server has no business sending.
Nothing else catches this: `skills/*` is consumer-owned, so it is absent
from the SDK's cacheable-method registry and a modern server answering
`{ skills: [] }` was reaching the conformance UI as a clean list.
- skills.ts: count `frontmatter.description` (and `name`) length in Unicode
CODE POINTS. `String.length` counts UTF-16 code units, so 600 non-BMP
characters measured as 1200 and a perfectly valid description was
reported `malformed-description` — a conforming server failed by an
off-by-encoding, which is the direction this module works hardest to
avoid. The Agent Skills reference validator uses Python `len()`.
- #2248 narrowed: the `skills/list` half is settled here; what remains is
whether `skills/get` carries the same attributes.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
All three findings were the same underlying inconsistency: URI comparisons
on raw strings, in a flow that elsewhere deliberately treats normalized
equivalents as the same resource. One `skillUriIdentity` helper now backs
every comparison, so they cannot disagree.
- skills.ts: `manifest-missing-self` compares identities, so a manifest
listing the RFC-equivalent `skill://demo/%53KILL.md` is recognized as the
entry's own file — it is fetchable as that file, so reporting it missing
was the tool disagreeing with itself.
- skills.ts: `skillEntriesMatch` normalizes the entry URI and every manifest
URI before comparing, so a server that canonicalizes an escape between the
listing and the fetch is not reported as a changed snapshot.
- SkillsScreen: the `wrongUri` check uses the same identity, so a
canonicalizing server is not accused of answering for a different skill —
the read path already accepts exactly that equivalence.
- skills.ts: apply the Agent Skills name grammar to the RAW value. Trimming
first let `" demo "` pass, and whitespace is not in the grammar — so an
entry could report "Conforms" with a name that can never equal its URI
path segment. The trimmed copy now only distinguishes absent from invalid.
- skills.ts: add `malformed-description` for a description above the
1024-character Agent Skills limit, with boundary coverage.
- inspectorClient-skills.test: justify the `as unknown as` per AGENTS.md —
both fields are `private` with no public setter, the asserted shape is
exactly what the class declares, and the alternative is a live connection.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- skills.ts: apply the two RFC 3986 §6.2.2 percent-encoding normalizations
the URL parser does not — decode an escape standing for an unreserved
character, and upper-case the hex of every escape that remains. `URL.href`
leaves `%72eference.md` encoded, so a server echoing an RFC-equivalent
form of the URI we asked for was rejected by `onReadSkillFile` as a
different resource, and an encoded name segment produced a false
`name-path-mismatch`. Both are the tool calling a conforming server wrong.
- oauthResume.test: assert the Skills restore path. It was wired into the
setters but never checked, and the comprehensive present-value and
undefined-fallback cases omitted Skills entirely. Adds it to both, plus a
case restoring a REAL saved selection rather than the EMPTY value — a bug
that always wrote the default would have passed the others.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- skills.ts: validate `frontmatter.name` against the Agent Skills format
(1–64 lowercase alphanumerics and hyphens, no leading, trailing or
consecutive hyphen). Checking only for non-emptiness let `Bad Name` read
as "Conforms" — and the name is not decorative: it must equal the URI
path segment, so a name that cannot appear in a URI is a contradiction
the entry cannot satisfy. Suppressed when the name is absent entirely,
which `missing-name` already reports.
- skills.ts: detect duplicates on the NORMALIZED identity. Containment and
the read that fetches the bytes both treat normalized-equivalents as one
resource, so `skill://demo/SKILL.md` and `skill://demo/x/../SKILL.md`
were passing as two distinct files while naming one. The finding still
reports the raw URI, and two different unparseable URIs stay distinct.
- SkillsScreen: run `checkSkillConformance` on the fetched `skills/get`
entry and treat an error — or an entry answering for a different URI —
as invalid (red), not as "a different snapshot" (yellow). A fresh
point-in-time read excuses a CHANGE; it does not excuse a violation, and
answering with another skill is never a refresh of the one requested.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- skills.ts: stop sorting `resources` arrays recursively. Only the entry's
OWN manifest is a set; `frontmatter` is verbatim arbitrary JSON, so a
custom `frontmatter.metadata.resources` array was being sorted too and
two genuinely different frontmatters compared equal. The manifest sort is
now done once, at the top level, and every other array keeps its order.
- SkillsScreen: invalidate on the whole selected entry, not just its
manifest. The `skills/get` comparison covers `frontmatter`, so a refresh
that changed only a description left a stale "matches skills/list"
verdict on screen — computed against an entry that no longer existed.
Re-verifying after a metadata-only refresh is the cheap direction to be
wrong in; showing a match against a different entry is not.
- SkillsScreen: give each "Verify all" invocation a token, so a finalizer
can only ever clear its own batch rather than any batch with a matching
manifest key.
- SkillsScreen.stories: supply `onGetSkill`. Every story rendered the
"Fetch with skills/get" button, and clicking it threw.
On the batch token: the A → B → A sequence the review describes is not
actually reachable, because the button is disabled whenever the in-flight
batch's key matches the selection — returning to A finds it disabled, not
clickable. The token is defence in depth for the same property, and the
test asserts what is really guaranteed rather than the unreachable path.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
Two of these reverse round 4, which asked for the opposite. Where the
readings conflict I took the permissive one: a wrong tightening rejects
conforming servers, a wrong loosening only fails to report something.
- skills.ts: stop requiring the `skill:` scheme. SEP-2640 says a server
SHOULD use `skill://` and explicitly allows a domain-native scheme, so
round 4's requirement handed a conforming `github://…` skill a false
`malformed-uri` and skipped its name and root checks. Containment is
scheme-independent — it compares against THIS entry's own root — so the
traversal fix that requirement came packaged with is unaffected.
- skills.ts: the 512-entry and 16 MiB limits are warnings. Both are
SHOULD NOTs for a server and MAYs for a host, so calling them errors
contradicted the "error = a MUST was broken" contract round 4
established and told authors a permitted skill was invalid.
- skills.ts: `skillEntriesMatch` compares canonically — keys sorted,
manifest sorted by URI. `JSON.stringify` treated key order and manifest
order as differences, though neither carries meaning.
- SkillsScreen: a differing `skills/get` is "a different snapshot"
(yellow), not a disagreement (red). The SEP defines it as a fresh
point-in-time read, so a skill that changed since the listing
legitimately differs.
- useServerCommands: route `onGetSkill` through the command-scoped OAuth
recovery like every other server command. An expired authorization
rendered an error and stopped there — no reauthorization, no retry.
- test-servers/skills.ts: stamp the modern base result envelope
(`resultType` / `ttlMs` / `cacheScope`) on every skills result. The SDK
stamps it only for methods in its own codec, and `skills/*` are
consumer-owned, so a 2026-era connection was receiving results without
it. Unconditional rather than per era: the modern leg builds a server
per request, so there is no era to branch on at registration time, and
on legacy they are three members no codec inspects.
- composable-test-server: remove the `skills.directoryRead` option. It was
publicly settable and advertised a method nothing serves, producing the
exact false capability the fixture exists to help catch. `skills` is now
a plain boolean; the flag returns in phase 3 (#2248) with its handler.
Still not changed: whether a modern `skills/list` RESULT SCHEMA must
require that envelope. Stamping it server-side is free; requiring it
client-side would reject servers on a reading nobody has checked against
the normative text. #2248 owns settling it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- SkillsScreen: actually call `skills/get`. The client method and its
tests existed but no production caller invoked it, so #2234's acceptance
criterion ("skills/get retrieves a single entry") was unmet and a server
author's required handler could not be exercised. The detail pane now
fetches the selected URI on demand and reports whether the fetched entry
AGREES with the one skills/list advertised — both describe the same
skill, so a disagreement is a server bug only a side-by-side fetch shows.
- core/mcp/sha256.ts: a dependency-free SHA-256, used when `crypto.subtle`
is absent. `SubtleCrypto` needs a secure context, and this app is
documented as servable over plain HTTP on a LAN IP — where every skill
verification threw and the UI reported a read failure for files it had
fetched fine. Checked against the FIPS 180-4 vectors and differentially
against WebCrypto.
- skills.ts: require the `skill:` scheme in `normalizeSkillUri`. Checking
only that a URI was hierarchical let `https://demo/SKILL.md` pass the
name and root checks — a manifest pointing anywhere on the web, reported
as conforming.
- skills.ts: `missing-digest` and `missing-size` are errors. Both are
required fields, and an omitted `size` is what lets a server slip past
the 16 MiB pre-fetch limit while the UI reports zero errors. `warning`
is now reserved for what is legal yet unverifiable — `"dynamic"`.
- SkillsScreen: key the "Verify all" batch guard to the manifest. A global
flag left a newly selected skill's button disabled until the previous
skill's reads settled — forever, if one hung.
Not changed, deliberately: whether a modern-era `skills/list` result MUST
carry the SEP-2549 caching attributes. #2234's analysis records it as open
and the review asserts the opposite; neither reading was checked against
the normative text. Leaving the schema permissive accepts a server that
omits them, while tightening on a wrong reading would reject conforming
responses — the more expensive direction. `skillsSchemas.ts` states this
and #2248 settles it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- skills.ts: decide root containment on NORMALIZED URIs. A raw prefix
check passed `skill://acme/billing/refunds/../other.md`, which starts
with the advertised root but resolves outside it — a traversal the
conformance report was reporting as clean.
- skills.ts: `normalizeSkillUri` also rejects a relative string, so
`demo/SKILL.md` is `malformed-uri` rather than a skill path, and an
opaque-path URI (`skill:demo/..`), which the parser leaves un-normalized
and on which containment cannot be decided.
- skills.ts: `missing-description` is an error. SEP-2640 requires it, so
an absent one must not read as "0 errors" in the conformance summary.
- managedSkillsState: call `markResponseRejected` for a decode rejection,
as every managed list does. An invalid `skills/list` result was showing
in the Protocol tab as a clean success.
- SkillsScreen: per-row attempt token. The manifest key cannot tell two
verifications of the SAME row apart, so a double click (or a row button
pressed during "Verify all") let an older read finish last and overwrite
the newer verdict.
- SkillsScreen: disable "Verify all" while a batch runs. The concurrency
cap is per invocation, so repeated clicks stacked pools — 4, then 8,
then 12.
- SkillsScreen: include the finding index in each issue alert's key. Three
identical URIs produce two `duplicate-resource` findings with the same
code and URI, and React was free to drop the extras — hiding findings in
exactly the malformed input this view exists to inspect.
- test-servers/skills.ts: register `skills/list` and `skills/get` through
the PUBLIC `setRequestHandler` with explicit param schemas. The private
`_requestHandlers` map is now reached only to wrap `resources/read`,
which has to chain onto the SDK's handler rather than replace it — the
one thing the public API cannot express, and the comment now says so
instead of citing the tasks fixture.
- test-servers/skills.ts: raise `-32602` for an unknown `skills/get` URI.
A plain Error mapped to a generic server failure, making the fixture
non-conforming outside its three documented bad cases.
- clients/web/README.md: the paragraph named four contracts while still
saying the smoke "drives all three".
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- SkillsScreen: key verdicts and React elements by manifest ROW INDEX,
not URI. The checker deliberately tolerates a duplicated URI so it can
report `duplicate-resource`; a URI key collided those rows into one
verdict, so verifying either updated both and "Verify all" raced two
different digest/size declarations into the same slot.
- SkillsScreen: hold the invalidation generation in React state keyed by
the manifest, not a ref bumped during render. `useValueChange` runs its
callback during render and requires setState-only purity — an abandoned
render left the ref incremented and silently discarded a live
verification.
- SkillsScreen: title a size disagreement "Size mismatch" and render its
reason. `verifySkillResource` catches it before hashing, so the alert
was showing "actual undefined" under "Digest mismatch".
- SkillsScreen: pass `contents` to ContentViewer so a base64 SKILL.md
renders. The text-block form substituted "" and painted a blank preview
for a file verification had just read correctly.
- skills.ts: add `malformed-size` for a size that is not a non-negative
safe integer, and exclude such values from the 16 MiB total. A negative
one could pull the sum back under the limit and hide a violation.
- managedSkillsState: make the overlap guard per-session instead of a
boolean. A disconnect during an in-flight walk left it set, so the
reconnect's own load no-oped and was never retried — permanently, if
the stale request never settled. A stale `finally` can no longer clear
the live session's guard either.
- skillsSchemas: require the `{ skill }` envelope for `skills/get`. The
accepted SEP settles it, and normalizing an inline entry would let a
non-conforming response past the one place that could report it.
- #2248 and the PR description: corrected — they said
`ReadResourceDirectoryResultSchema` was already declared, which round 1
removed. #2248 now owns defining it, and records the frontmatter
cross-check gap too.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
- skills.ts: report a manifest that omits the skill's own SKILL.md
(an empty list included), duplicate URIs, entries outside the skill
root, and a missing size. `Conforms` was reachable for manifests that
break invariants SEP-2640 states.
- skills.ts: cross-check the declared byte length before hashing. A size
that disagrees fails verification on its own — the digest is taken over
the bytes the server served, so agreeing with it says nothing about
whether the manifest describes them.
- skills.ts: copy the view instead of slicing its backing store in
`sha256Digest`. `SharedArrayBuffer.prototype.slice()` returns another
SharedArrayBuffer, which `crypto.subtle.digest` rejects — the cast
claimed to handle the exact input that would have thrown. No cast now.
- skills.ts: state the one obligation NOT checked here — that an entry's
frontmatter matches the fetched SKILL.md's. The digest cannot cover it,
and closing it needs a YAML parser, so it is tracked on #2248.
- managedSkillsState: cap the walk at LIST_MAX_PAGES. The repeated-cursor
guard only catches a server stuck on one cursor; endlessly unique ones
walked forever. Raises rather than truncating, like the salvage walk.
- managedSkillsState: gate every write on a session generation, so a walk
that resolves after a disconnect or destroy cannot repopulate a cleared
store or deliver the previous session's skills into the next.
- inspectorClient: send a cursor when it is `!== undefined`, not when it
is truthy. An opaque cursor may be `""`, and dropping it re-requested
page one — which the store then reported as a repeated-cursor failure.
- SkillsScreen: key verdict invalidation on the manifest (URI + digests +
sizes), not the URI alone. A Refresh that changed the manifest left a
green badge attached to a digest nothing had checked.
- SkillsScreen: epoch-guard every read continuation, so a fetch that
resolves after the selection moved on cannot write into the new one.
- SkillsScreen: bound "Verify all" to 4 concurrent reads. A conforming
manifest may hold 512 files.
- skillsSchemas: drop the guessed `resources/directory/read` result
schema. Nothing calls it, so an unverified shape could sit wrong
indefinitely; phase 3 adds it against the normative text.
- skills-http.json: declare the extension bare. It advertised
`directoryRead: true` with no handler, so Connection Info reported
"Supported" for a method that answers -32601.
- types.ts: restore the Tasks doc comment the Skills interface displaced.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
Adds detection, enumeration, and conformance checking for the Skills
extension (`io.modelcontextprotocol/skills`) — phases 1 and 2 of #2234,
which is everything its Acceptance list names.
Skills is a *server*-declared extension, read off the connecting server's
`capabilities.extensions`, so it is deliberately absent from
`ADVERTISABLE_EXTENSIONS` — that registry is what the Inspector advertises
and the user toggles, and an entry there would be a meaningless toggle.
`skills/list` and `skills/get` are consumer-owned extension methods that
neither era codec defines, so the SDK's era gate skips them and they go out
as ordinary `client.request` calls with explicit result schemas. The
raw-wire channel modern `tasks/*` needs is not used, and the Skills tab is
not era-gated: a legacy-era server that declares the extension is serving it.
The checks are the point, not the list view. `core/mcp/skills.ts` reports
each obligation SEP-2640 states — the name/path invariant, the digest
format, the 512-entry and 16 MiB limits, and `resources: "dynamic"`, which
means integrity cannot be verified at all. Digest verification hashes the
fetched bytes with WebCrypto and returns a mismatch with both digests
attached rather than throwing, because showing a mismatch loudly is the
whole value proposition.
Files are fetched on demand: SEP-2640 is explicit that a `resources/read`
of a `SKILL.md` is not a load and confers no standing, so none of the SEP's
host machinery is implemented.
The `skills-http` fixture serves four skills over two pages, three of them
deliberately non-conforming — without those the verification code is
untestable.
Phase 3 (CLI, TUI, `resources/directory/read`, paged mode) is #2248.
Closes#2234
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018kfrH3uRNUM4JAk1reKtyY
Signed-off-by: cliffhall <cliff@futurescale.com>
cliffhall