nongnu: Add node-modelcontextprotocol-sdk.

* nongnu/packages/claude-code.scm (node-modelcontextprotocol-sdk): New variable.

nongnu/packages/claude-code.scm

@@ -3206,3 +3206,66 @@ framework.")
 Workers, supporting drafts 4, 7, 2019-09, and 2020-12.")
     (license license:expat)))
 
+(define-public node-modelcontextprotocol-sdk
+  (package
+    (name "node-modelcontextprotocol-sdk")
+    (version "1.25.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append
+             "https://registry.npmjs.org/@modelcontextprotocol/sdk/-/sdk-"
+             version ".tgz"))
+       (sha256
+        (base32 "0341ip1l02229p7pvlv3g28dij883v20kb0wnc1l6ljidzjfrfvz"))))
+    (build-system node-build-system)
+    (arguments
+     (list
+      #:tests? #f
+      #:phases
+      #~(modify-phases %standard-phases
+           (add-after 'patch-dependencies 'delete-dev-dependencies
+             (lambda _
+               (modify-json (delete-dev-dependencies))))
+           (add-after 'delete-dev-dependencies 'delete-build-scripts
+             (lambda _
+               (with-atomic-json-file-replacement
+                 (lambda (pkg)
+                   (map (lambda (kv)
+                          (if (equal? (car kv) "scripts")
+                              (cons "scripts"
+                                    (filter
+                                     (lambda (s)
+                                       (not
+                                        (member (car s)
+                                                '("build" "prepare"
+                                                  "prepack" "postinstall"))))
+                                     (cdr kv)))
+                              kv))
+                        pkg)))))
+           (delete 'build))))
+    (inputs
+     (list
+      node-hono-node-server
+      node-ajv
+      node-ajv-formats
+      node-content-type
+      node-cors
+      node-cross-spawn
+      node-eventsource
+      node-eventsource-parser
+      node-express
+      node-express-rate-limit
+      node-jose
+      node-json-schema-typed
+      node-pkce-challenge
+      node-raw-body
+      node-zod
+      node-zod-to-json-schema
+      node-cfworker-json-schema))
+    (home-page "https://www.npmjs.com/package/@modelcontextprotocol/sdk")
+    (synopsis "Model Context Protocol SDK")
+    (description "This package implements the Model Context Protocol for connecting AI
+models to external tools and data sources.")
+    (license license:expat)))
+