chore(skills): take SEP-2640 constants and schemas from the SDK, move the rest to core/extension/skills

.claude/skills/project-structure/SKILL.md

@@ -45,7 +45,7 @@ an MCP server, the request/response lifecycle, and a set of state stores.
 | `core/mcp/state/` | The stores `core/react/` hooks read |
 | `core/auth/` | OAuth end to end — providers, discovery, storage, endpoint overrides, scopes, revocation, mid-session recovery — split into isomorphic logic plus `browser/`, `node/` and `remote/` backends |
 | `core/auth/node/` | Node OAuth storage + loopback callback server, **and** the `SecretStore` backends (keychain / file / memory) and their selection policy |
-| `core/extension/<name>/` | Host-side adapters for MCP extensions whose protocol an upstream SDK owns. `tasks/` wraps `@modelcontextprotocol/ext-tasks` with what that package leaves to its host: the raw `rawDispatch` channel, progress routing, error identity, and task-view conversions. Imports nothing from `InspectorClient`; host state arrives through narrow interfaces |
+| `core/extension/<name>/` | Host-side adapters for MCP extensions whose protocol an upstream SDK owns. `tasks/` wraps `@modelcontextprotocol/ext-tasks` with what that package leaves to its host: the raw `rawDispatch` channel, progress routing, error identity, and task-view conversions. `skills/` keeps what `@modelcontextprotocol/client/ext/skills` leaves to an inspector: permissive entry schemas (the SDK's refuse a non-conforming entry), the per-check conformance and verification report, and `SKILL.md` frontmatter parsing; constants, limits and the directory-read schema come from the SDK. Imports nothing from `InspectorClient`; host state arrives through narrow interfaces |
 | `core/cli/` | Node-only surface the one-shot CLI and `mcpdo` both run on (#2461): `error-handler` (exit codes, `CliExitCodeError`, the error envelope), the method handlers and their option/format types (`handlers/`), the interactive OAuth connect flow (`cliOAuth`, `cli-oauth-navigation`) and output helpers (`style`, `utils/awaitable-log`). One-shot-only output (`emit-result`, `consume-outcome`, `servers-write`, …) stays in `clients/cli/src` |
 | `core/client/` | Install-level client config (`client.json`): browser-safe parse plus Node load/save, remote backend, secrets, runner |
 | `core/json/` | JSON + parameter/argument conversion; the schema normalizations all three form builders share (nullable unions, root composition) and the tool-schema portability lint |

AGENTS.md

@@ -53,6 +53,8 @@ inspector/
 │   │                 exit codes, interactive OAuth flow, output styling); tested + gated by clients/cli
 │   ├── client/       Install-level client config (`client.json`)
 │   ├── extension/    Host-side adapters for MCP extensions whose protocol an upstream SDK owns
+│   │   ├── skills/   What the SDK's Skills client leaves to an inspector: permissive entry schemas, the
+│   │   │             per-check conformance + verification report, SKILL.md frontmatter parsing
 │   │   └── tasks/    The Inspector's glue around `@modelcontextprotocol/ext-tasks` (raw dispatch, progress routing)
 │   ├── json/         JSON/schema utilities shared by all three form builders
 │   ├── logging/      Silent pino logger singleton

clients/cli/__tests__/run-method-skills.test.ts

@@ -6,9 +6,9 @@ import {
 } from "@inspector/core/cli/handlers/skills-verify.js";
 import { EXIT_CODES } from "@inspector/core/cli/error-handler.js";
 import type { InspectorClient } from "@inspector/core/mcp/index.js";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas.js";
-import { sha256Digest } from "@inspector/core/mcp/skills.js";
-import type { SkillVerifyReport } from "@inspector/core/mcp/skillsVerification.js";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas.js";
+import { sha256Digest } from "@inspector/core/extension/skills/conformance.js";
+import type { SkillVerifyReport } from "@inspector/core/extension/skills/verification.js";
 
 /**
  * The three SEP-2640 methods the CLI gained in #2248, plus `--verify`.

clients/cli/__tests__/skills-verify-cli.test.ts

@@ -3,7 +3,7 @@ import {
   createTestServerHttp,
   createTestServerInfo,
 } from "@modelcontextprotocol/inspector-test-server";
-import type { SkillVerifyReport } from "@inspector/core/mcp/skillsVerification.js";
+import type { SkillVerifyReport } from "@inspector/core/extension/skills/verification.js";
 import { runCli } from "../src/cli.js";
 import { consumeMethodOutcome } from "../src/handlers/consume-outcome.js";
 import { EXIT_CODES } from "@inspector/core/cli/error-handler.js";

clients/mcpdo/__tests__/skills-budget-hint.test.ts

@@ -17,7 +17,7 @@ import {
   createTestServerHttp,
   createTestServerInfo,
 } from "@modelcontextprotocol/inspector-test-server";
-import type { SkillVerifyReport } from "@inspector/core/mcp/skillsVerification.js";
+import type { SkillVerifyReport } from "@inspector/core/extension/skills/verification.js";
 import { runMcp, type McpResult } from "./helpers/mcp-runner.js";
 import {
   createTestConfig,

clients/tui/__tests__/SkillsTab.test.tsx

@@ -2,9 +2,12 @@ import React from "react";
 import { describe, it, expect, vi } from "vitest";
 import { render } from "./helpers/renderTui";
 import type { InspectorClient } from "@inspector/core/mcp/index.js";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas.js";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas.js";
 import { AuthRecoveryRequiredError } from "@inspector/core/auth/challenge.js";
-import { sha256Digest, textToBytes } from "@inspector/core/mcp/skills.js";
+import {
+  sha256Digest,
+  textToBytes,
+} from "@inspector/core/extension/skills/conformance.js";
 
 // MUST mock ink-scroll-view: the real ScrollView renders a placeholder minimap
 // in the non-TTY test env and never mounts its children.

clients/tui/src/components/SkillsTab.tsx

@@ -36,17 +36,17 @@ import {
   skillEntryKey,
   skillUriIdentity,
   type SkillIssue,
-} from "@inspector/core/mcp/skills.js";
+} from "@inspector/core/extension/skills/conformance.js";
 import {
   DYNAMIC_RESOURCES,
   type SkillEntry,
-} from "@inspector/core/mcp/skillsSchemas.js";
+} from "@inspector/core/extension/skills/schemas.js";
 import {
   verifySkills,
   type SkillBudgetHint,
   type SkillFileReport,
   type SkillVerifyReport,
-} from "@inspector/core/mcp/skillsVerification.js";
+} from "@inspector/core/extension/skills/verification.js";
 import { useSelectableList } from "../hooks/useSelectableList.js";
 import { errorMessage } from "../utils/errorText.js";
 import { useListFilter } from "../hooks/useListFilter.js";

clients/web/src/App.tsx

@@ -10,7 +10,7 @@ import type {
 } from "@modelcontextprotocol/client";
 import { InspectorClient } from "@inspector/core/mcp/index.js";
 import { getServerType } from "@inspector/core/mcp/config.js";
-import { getSkillsExtension } from "@inspector/core/mcp/skills.js";
+import { getSkillsExtension } from "@inspector/core/extension/skills/conformance.js";
 import type { JsonValue } from "@inspector/core/mcp/index.js";
 
 import type { TypedEventGeneric } from "@inspector/core/mcp/typedEventTarget.js";

clients/web/src/components/groups/ConnectionInfoContent/ConnectionInfoContent.tsx

@@ -28,7 +28,7 @@ import {
 import { useTickingClock } from "../../../hooks/useTickingClock";
 import type { ListCount } from "../../../utils/listCount";
 import { TASKS_EXTENSION_KEY } from "@inspector/core/extension/tasks/constants.js";
-import { getSkillsExtension } from "@inspector/core/mcp/skills.js";
+import { getSkillsExtension } from "@inspector/core/extension/skills/conformance.js";
 import type { OAuthClientRegistrationKind } from "@inspector/core/auth/types.js";
 import {
   CapabilityItem,

clients/web/src/components/groups/ServerSettingsForm/ServerSettingsForm.tsx

@@ -47,7 +47,7 @@ import {
 import {
   isSkillCatalogLimit,
   resolveSkillCatalogBudget,
-} from "@inspector/core/mcp/skills.js";
+} from "@inspector/core/extension/skills/conformance.js";
 import type { Root } from "@modelcontextprotocol/client";
 
 /**

clients/web/src/components/screens/SkillsScreen/SkillsScreen.stories.tsx

@@ -2,8 +2,8 @@ import { useState } from "react";
 import type { ComponentProps } from "react";
 import type { Meta, StoryObj } from "@storybook/react-vite";
 import { expect, fn, userEvent, waitFor, within } from "storybook/test";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas";
-import { sha256Bytes } from "@inspector/core/mcp/sha256";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas";
+import { sha256Bytes } from "@inspector/core/extension/skills/sha256";
 import { SkillsScreen } from "./SkillsScreen";
 import type { SkillsUiState } from "./SkillsScreen";
 import { EMPTY_SKILLS_UI } from "../screenUiState";

clients/web/src/components/screens/SkillsScreen/SkillsScreen.test.tsx

@@ -1,8 +1,11 @@
 import { StrictMode, useState } from "react";
 import { describe, it, expect, vi } from "vitest";
 import userEvent from "@testing-library/user-event";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas";
-import { sha256Digest, textToBytes } from "@inspector/core/mcp/skills";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas";
+import {
+  sha256Digest,
+  textToBytes,
+} from "@inspector/core/extension/skills/conformance";
 import {
   act,
   renderWithMantine,

clients/web/src/components/screens/SkillsScreen/SkillsScreen.tsx

@@ -22,11 +22,11 @@ import type {
   DirectoryReadResult,
   SkillEntry,
   SkillResource,
-} from "@inspector/core/mcp/skillsSchemas.js";
+} from "@inspector/core/extension/skills/schemas.js";
 import {
   DIRECTORY_MIME_TYPE,
   DYNAMIC_RESOURCES,
-} from "@inspector/core/mcp/skillsSchemas.js";
+} from "@inspector/core/extension/skills/schemas.js";
 import {
   checkSkillConformance,
   checkSkillFrontmatterMatch,
@@ -44,12 +44,12 @@ import {
   type SkillFileContents,
   type SkillIssue,
   type SkillVerification,
-} from "@inspector/core/mcp/skills.js";
+} from "@inspector/core/extension/skills/conformance.js";
 import { CodeHighlight } from "../../elements/CodeHighlight/CodeHighlight";
 import { ContentViewer } from "../../elements/ContentViewer/ContentViewer";
 import { ListToggle } from "../../elements/ListToggle/ListToggle";
 import { useValueChange } from "../../../hooks/useValueChange";
-import { splitSkillFile } from "@inspector/core/mcp/skillFile.js";
+import { splitSkillFile } from "@inspector/core/extension/skills/skillFile.js";
 import {
   inferMimeFromUri,
   isGenericMime,

clients/web/src/components/views/InspectorView/InspectorView.tsx

@@ -13,7 +13,7 @@ import type { ServerEntry } from "@inspector/core/mcp/types.js";
 import { isTerminalStatus } from "@inspector/core/mcp/types.js";
 import { isAppTool } from "@inspector/core/mcp/apps.js";
 import { TASKS_EXTENSION_KEY } from "@inspector/core/extension/tasks/constants.js";
-import { isSkillsExtensionSupported } from "@inspector/core/mcp/skills.js";
+import { isSkillsExtensionSupported } from "@inspector/core/extension/skills/conformance.js";
 import { ViewHeader } from "../../groups/ViewHeader/ViewHeader";
 import { VersionBadge } from "../../elements/VersionBadge/VersionBadge";
 import { CopyrightBadge } from "../../elements/CopyrightBadge/CopyrightBadge";

clients/web/src/components/views/InspectorView/types.ts

@@ -60,9 +60,9 @@ import type {
 } from "../../screens/ResourcesScreen/ResourcesScreen";
 import type { LogsUiState } from "../../screens/LoggingScreen/LoggingScreen";
 import type { SkillsUiState } from "../../screens/SkillsScreen/SkillsScreen";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas.js";
-import type { SkillFileContents } from "@inspector/core/mcp/skills.js";
-import type { DirectoryReadResult } from "@inspector/core/mcp/skillsSchemas.js";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas.js";
+import type { SkillFileContents } from "@inspector/core/extension/skills/conformance.js";
+import type { DirectoryReadResult } from "@inspector/core/extension/skills/schemas.js";
 import type { TasksUiState } from "../../screens/TasksScreen/TasksScreen";
 import type { ProtocolUiState } from "../../screens/ProtocolScreen/ProtocolScreen";
 import type { NetworkUiState } from "../../screens/NetworkScreen/NetworkScreen";

clients/web/src/hooks/useInspectorStores.ts

@@ -13,7 +13,7 @@ import type {
   ResourceSubscriptionStreamState,
   StderrLogEntry,
 } from "@inspector/core/mcp/types.js";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas.js";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas.js";
 import type { InspectorClient } from "@inspector/core/mcp/index.js";
 import { ManagedToolsState } from "@inspector/core/mcp/state/managedToolsState.js";
 import { ManagedPromptsState } from "@inspector/core/mcp/state/managedPromptsState.js";

clients/web/src/hooks/useServerCommands.tsx

@@ -34,10 +34,10 @@ import type {
 } from "../components/screens/ToolsScreen/ToolsScreen";
 import type { GetPromptState } from "../components/screens/PromptsScreen/PromptsScreen";
 import type { ReadResourceState } from "../components/screens/ResourcesScreen/ResourcesScreen";
-import type { SkillFileContents } from "@inspector/core/mcp/skills.js";
-import type { DirectoryReadResult } from "@inspector/core/mcp/skillsSchemas.js";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas.js";
-import { normalizeSkillUri } from "@inspector/core/mcp/skills.js";
+import type { SkillFileContents } from "@inspector/core/extension/skills/conformance.js";
+import type { DirectoryReadResult } from "@inspector/core/extension/skills/schemas.js";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas.js";
+import { normalizeSkillUri } from "@inspector/core/extension/skills/conformance.js";
 import { UrlElicitationErrorToastMessage } from "../components/elements/Toasts/UrlElicitationErrorToastMessage";
 import {
   errorCodeOf,

clients/web/src/test/core/mcp/skills.test.ts → clients/web/src/test/core/extension/skills/conformance.test.ts

@@ -1,7 +1,7 @@
 import { describe, it, expect } from "vitest";
 import type { ServerCapabilities } from "@modelcontextprotocol/client";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas";
-import { SKILLS_EXTENSION_KEY } from "@inspector/core/mcp/skillsSchemas";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas";
+import { SKILLS_EXTENSION_KEY } from "@inspector/core/extension/skills/schemas";
 import {
   SKILL_MAX_RESOURCE_ENTRIES,
   SKILL_MAX_TOTAL_BYTES,
@@ -21,7 +21,7 @@ import {
   textToBytes,
   totalSkillBytes,
   verifySkillResource,
-} from "@inspector/core/mcp/skills";
+} from "@inspector/core/extension/skills/conformance";
 
 /** The digest of the string "hello", precomputed so the assertion is a fact
  * about SHA-256 rather than a restatement of what the code just did. */

clients/web/src/test/core/mcp/skillsSchemas.test.ts → clients/web/src/test/core/extension/skills/schemas.test.ts

@@ -14,7 +14,11 @@ import {
   SKILLS_GET_METHOD,
   SKILLS_LIST_METHOD,
   SkillEntrySchema,
-} from "@inspector/core/mcp/skillsSchemas";
+} from "@inspector/core/extension/skills/schemas";
+import {
+  ReadResourceDirectoryResultSchema,
+  SKILLS_EXTENSION_ID,
+} from "@modelcontextprotocol/core/ext/skills";
 
 const ENTRY = {
   uri: "skill://demo/SKILL.md",
@@ -25,6 +29,15 @@ const ENTRY = {
 };
 
 describe("skills wire constants", () => {
+  // #2804: the SDK owns these, so a spec revision lands with an SDK bump. A
+  // local restatement would still pass the literal checks below.
+  it("takes the extension id and the directory schema from the SDK", () => {
+    expect(SKILLS_EXTENSION_KEY).toBe(SKILLS_EXTENSION_ID);
+    expect(ModernDirectoryReadResultSchema).toBe(
+      ReadResourceDirectoryResultSchema,
+    );
+  });
+
   it("names the extension and its two required methods", () => {
     expect(SKILLS_EXTENSION_KEY).toBe("io.modelcontextprotocol/skills");
     expect(SKILLS_LIST_METHOD).toBe("skills/list");

clients/web/src/test/core/mcp/sha256.test.ts → clients/web/src/test/core/extension/skills/sha256.test.ts

@@ -1,6 +1,9 @@
 import { describe, it, expect } from "vitest";
-import { sha256Bytes } from "@inspector/core/mcp/sha256";
-import { sha256Digest, textToBytes } from "@inspector/core/mcp/skills";
+import { sha256Bytes } from "@inspector/core/extension/skills/sha256";
+import {
+  sha256Digest,
+  textToBytes,
+} from "@inspector/core/extension/skills/conformance";
 
 const hex = (bytes: Uint8Array) =>
   Array.from(bytes)

clients/web/src/test/core/mcp/skillFile.test.ts → clients/web/src/test/core/extension/skills/skillFile.test.ts

@@ -2,7 +2,7 @@ import { describe, it, expect } from "vitest";
 import {
   parseSkillFrontmatter,
   splitSkillFile,
-} from "@inspector/core/mcp/skillFile.js";
+} from "@inspector/core/extension/skills/skillFile.js";
 
 describe("splitSkillFile", () => {
   it("separates a leading frontmatter fence from the body", () => {

clients/web/src/test/core/mcp/skillFileBytes.test.ts → clients/web/src/test/core/extension/skills/skillFileBytes.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect } from "vitest";
-import { skillFileBytes } from "@inspector/core/mcp/skills.js";
+import { skillFileBytes } from "@inspector/core/extension/skills/conformance.js";
 
 describe("skillFileBytes", () => {
   it("encodes a text content block as UTF-8", () => {

clients/web/src/test/core/mcp/skillsVerification.test.ts → clients/web/src/test/core/extension/skills/verification.test.ts

@@ -3,11 +3,11 @@ import type { InspectorClientProtocol } from "@inspector/core/mcp/inspectorClien
 import {
   DYNAMIC_RESOURCES,
   type SkillEntry,
-} from "@inspector/core/mcp/skillsSchemas.js";
+} from "@inspector/core/extension/skills/schemas.js";
 import {
   SKILL_MAX_CATALOG_SKILLS,
   sha256Digest,
-} from "@inspector/core/mcp/skills.js";
+} from "@inspector/core/extension/skills/conformance.js";
 import { AuthRecoveryRequiredError } from "@inspector/core/auth/challenge.js";
 import {
   allSkillsVerified,
@@ -16,7 +16,7 @@ import {
   DEFAULT_SKILL_BUDGET_HINT,
   utf8Length,
   verifySkills,
-} from "@inspector/core/mcp/skillsVerification.js";
+} from "@inspector/core/extension/skills/verification.js";
 
 /**
  * `verifySkills` is the fetch-and-verify half of the SEP-2640 checks (#2248) —

clients/web/src/test/core/mcp/extensions.test.ts

@@ -8,7 +8,7 @@ import {
   isAdvertisedByDefault,
 } from "@inspector/core/mcp/extensions.js";
 import { TASKS_EXTENSION_KEY } from "@inspector/core/extension/tasks/constants.js";
-import { SKILLS_EXTENSION_KEY } from "@inspector/core/mcp/skillsSchemas.js";
+import { SKILLS_EXTENSION_KEY } from "@inspector/core/extension/skills/schemas.js";
 
 // The `ui` extension carries a non-empty advertisement value; the others are
 // declared with `{}`. Spelled out here so the map assertions stay readable.

clients/web/src/test/core/mcp/inspectorClient-skills.test.ts

@@ -1,7 +1,7 @@
 import { describe, it, expect, vi } from "vitest";
 import { InspectorClient } from "@inspector/core/mcp/inspectorClient.js";
 import type { ServerCapabilities } from "@modelcontextprotocol/client";
-import { SKILLS_EXTENSION_KEY } from "@inspector/core/mcp/skillsSchemas.js";
+import { SKILLS_EXTENSION_KEY } from "@inspector/core/extension/skills/schemas.js";
 import { SdkError, SdkErrorCode } from "@modelcontextprotocol/client";
 
 /**

clients/web/src/test/core/mcp/state/managedSkillsState.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeEach } from "vitest";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas";
 import {
   ManagedSkillsState,
   REPEATED_CURSOR_MESSAGE,

clients/web/src/test/core/react/useManagedSkills.test.tsx

@@ -1,6 +1,6 @@
 import { describe, it, expect, beforeEach } from "vitest";
 import { act, renderHook } from "@testing-library/react";
-import type { SkillEntry } from "@inspector/core/mcp/skillsSchemas";
+import type { SkillEntry } from "@inspector/core/extension/skills/schemas";
 import { FakeInspectorClient } from "@inspector/core/mcp/__tests__/fakeInspectorClient";
 import { ManagedSkillsState } from "@inspector/core/mcp/state/managedSkillsState";
 import { useManagedSkills } from "@inspector/core/react/useManagedSkills";

clients/web/src/test/integration/mcp/inspectorClient-skills.test.ts

@@ -2,12 +2,12 @@ import { describe, it, expect, afterEach } from "vitest";
 import { InspectorClient } from "@inspector/core/mcp/inspectorClient.js";
 import { createTransportNode } from "@inspector/core/mcp/node/transport.js";
 import { eraToVersionNegotiation } from "@inspector/core/mcp/types.js";
-import { getSkillsExtension } from "@inspector/core/mcp/skills.js";
+import { getSkillsExtension } from "@inspector/core/extension/skills/conformance.js";
 import { ManagedSkillsState } from "@inspector/core/mcp/state/managedSkillsState.js";
 import {
   allSkillsVerified,
   verifySkills,
-} from "@inspector/core/mcp/skillsVerification.js";
+} from "@inspector/core/extension/skills/verification.js";
 import {
   createTestServerHttp,
   type TestServerHttp,

core/cli/handlers/output-file.ts

@@ -21,7 +21,7 @@
  * with a file encoding would make `--format json --output x` ambiguous.
  */
 import { writeFile } from "node:fs/promises";
-import { base64ToBytes } from "../../mcp/skills.js";
+import { base64ToBytes } from "../../extension/skills/conformance.js";
 import { CliExitCodeError, EXIT_CODES } from "../error-handler.js";
 import type { McpResponse } from "./method-types.js";
 

core/cli/handlers/run-method.ts

@@ -9,7 +9,7 @@ import {
   ManagedSkillsState,
   MessageLogState,
 } from "../../mcp/state/index.js";
-import { SKILLS_EXTENSION_KEY } from "../../mcp/skillsSchemas.js";
+import { SKILLS_EXTENSION_KEY } from "../../extension/skills/schemas.js";
 import { CliExitCodeError, EXIT_CODES } from "../error-handler.js";
 import { collectAppInfo } from "./collect-app-info.js";
 import {
@@ -20,7 +20,7 @@ import {
 import {
   verifySkills,
   type SkillBudgetHint,
-} from "../../mcp/skillsVerification.js";
+} from "../../extension/skills/verification.js";
 import type {
   CliAppInfo,
   McpResponse,