fix(packaging): inline json-schema-typed in dist .d.mts; move validator provider types to subpath-only

The bundled server/client dist .d.mts files leaked two type references that
break downstream consumers with skipLibCheck:false (the TS default):

- types-*.d.mts imported 'json-schema-typed', which is not a dependency of
  server/client (only of core, which is bundled). Fixed by adding
  'json-schema-typed' to dts.resolve so the JSONSchema type is inlined.

- ajvProvider-*.d.mts referenced URIComponent without a declaration.
  ajv@8.18.0's .d.ts does `import { URIComponent } from "fast-uri"`, but
  fast-uri ships its types as `export = namespace`, which the dts bundler
  cannot destructure — it drops the import and leaves the bare reference.
  Fixed by removing the type-only re-exports of AjvJsonSchemaValidator /
  CfWorkerJsonSchemaValidator / CfWorkerSchemaDraft from the public root
  barrel: those classes/types are still exported from the dedicated
  /validators/ajv and /validators/cf-worker subpaths (and the runtime
  _shims conditional), so the inlined ajv type chunk is no longer reachable
  from index.d.mts. The codemod already routes v1 imports to the subpaths.

Also:
- @modelcontextprotocol/node package.json: remove typesVersions.sse entry
  pointing at nonexistent dist/sse.d.mts.
- server/client READMEs: note that TS >=6.0 needs "types": ["node"] in
  tsconfig (TS 6 dropped implicit @types inclusion; the published .d.mts
  references Buffer).

Verified: pnpm build:all + typecheck:all + docs:check green; fresh npm
install of packed tarballs + `npx tsc --noEmit` (NodeNext + bundler,
strict, skipLibCheck:false) is clean.

Author: felixweinberger

.changeset/validators-subpath-only.md

@@ -0,0 +1,6 @@
+---
+'@modelcontextprotocol/server': patch
+'@modelcontextprotocol/client': patch
+---
+
+`AjvJsonSchemaValidator`, `CfWorkerJsonSchemaValidator` and `CfWorkerSchemaDraft` types are now only exported from the `/validators/ajv` and `/validators/cf-worker` subpaths, not the package root. The codemod already routes v1 imports there.

packages/client/README.md

@@ -16,6 +16,8 @@ The MCP (Model Context Protocol) TypeScript client SDK. Build MCP clients that c
 npm install @modelcontextprotocol/client@alpha
 ```
 
+TypeScript ≥6.0 no longer auto-includes `@types/*` — add `"types": ["node"]` to your `tsconfig.json` `compilerOptions` (the published `.d.mts` references `Buffer`).
+
 ## Documentation
 
 - **[Repository README](https://github.com/modelcontextprotocol/typescript-sdk#readme)** — overview, package layout, examples

packages/client/tsdown.config.ts

@@ -20,7 +20,7 @@ export default defineConfig({
     shims: true,
     dts: {
         resolver: 'tsc',
-        resolve: ['ajv', 'ajv-formats'],
+        resolve: ['ajv', 'ajv-formats', 'json-schema-typed'],
         compilerOptions: {
             baseUrl: '.',
             paths: {

packages/core/src/exports/public/index.ts

@@ -129,10 +129,10 @@ export {
 export type { SpecTypeName, SpecTypes } from '../../types/specTypeSchema.js';
 export { isSpecType, specTypeSchemas } from '../../types/specTypeSchema.js';
 export type { StandardSchemaV1, StandardSchemaV1Sync, StandardSchemaWithJSON } from '../../util/standardSchema.js';
-// Validator providers are type-only here — import the runtime classes from the explicit
-// `@modelcontextprotocol/{client,server}/validators/{ajv,cf-worker}` subpaths to customise.
-export type { AjvJsonSchemaValidator } from '../../validators/ajvProvider.js';
-export type { CfWorkerJsonSchemaValidator, CfWorkerSchemaDraft } from '../../validators/cfWorkerProvider.js';
+// Validator provider classes (`AjvJsonSchemaValidator`, `CfWorkerJsonSchemaValidator`) are
+// intentionally NOT re-exported here — import them from the explicit
+// `@modelcontextprotocol/{client,server}/validators/{ajv,cf-worker}` subpaths so the
+// root entrypoint's bundled `.d.mts` doesn't pull the inlined ajv/cfworker type chunks.
 // fromJsonSchema is intentionally NOT exported here — the server and client packages
 // provide runtime-aware wrappers that default to the appropriate validator via _shims.
 export type { JsonSchemaType, JsonSchemaValidator, jsonSchemaValidator, JsonSchemaValidatorResult } from '../../validators/types.js';

packages/middleware/node/package.json

@@ -27,13 +27,6 @@
         }
     },
     "types": "./dist/index.d.mts",
-    "typesVersions": {
-        "*": {
-            "sse": [
-                "dist/sse.d.mts"
-            ]
-        }
-    },
     "files": [
         "dist"
     ],

packages/server/README.md

@@ -16,6 +16,8 @@ The MCP (Model Context Protocol) TypeScript server SDK. Build MCP servers that e
 npm install @modelcontextprotocol/server@alpha
 ```
 
+TypeScript ≥6.0 no longer auto-includes `@types/*` — add `"types": ["node"]` to your `tsconfig.json` `compilerOptions` (the published `.d.mts` references `Buffer`).
+
 Optional framework adapters: [`@modelcontextprotocol/express`](https://www.npmjs.com/package/@modelcontextprotocol/express), [`@modelcontextprotocol/hono`](https://www.npmjs.com/package/@modelcontextprotocol/hono),
 [`@modelcontextprotocol/node`](https://www.npmjs.com/package/@modelcontextprotocol/node).
 

packages/server/tsdown.config.ts

@@ -19,7 +19,7 @@ export default defineConfig({
     shims: true,
     dts: {
         resolver: 'tsc',
-        resolve: ['ajv', 'ajv-formats'],
+        resolve: ['ajv', 'ajv-formats', 'json-schema-typed'],
         compilerOptions: {
             baseUrl: '.',
             paths: {