Support Disabling SSL verification for testing

src/mcp/client/__main__.py

@@ -47,12 +47,17 @@ async def run_session(
         logger.info("Initialized")
 
 
-async def main(command_or_url: str, args: list[str], env: list[tuple[str, str]]):
+async def main(
+    command_or_url: str,
+    args: list[str],
+    env: list[tuple[str, str]],
+    verify_ssl: bool,
+):
     env_dict = dict(env)
 
     if urlparse(command_or_url).scheme in ("http", "https"):
         # Use SSE client for HTTP(S) URLs
-        async with sse_client(command_or_url) as streams:
+        async with sse_client(command_or_url, verify_ssl=verify_ssl) as streams:
             await run_session(*streams)
     else:
         # Use stdio client for commands
@@ -76,9 +81,24 @@ def cli():
         help="Environment variables to set. Can be used multiple times.",
         default=[],
     )
+    parser.add_argument(
+        "--disable-ssl-verification",
+        action='store_true',
+        default=False,
+        help="Disable SSL verification on HTTPS. SSL verification by default.",
+    )
 
     args = parser.parse_args()
-    anyio.run(partial(main, args.command_or_url, args.args, args.env), backend="trio")
+    anyio.run(
+        partial(
+            main,
+            args.command_or_url,
+            args.args,
+            args.env,
+            not args.disable_ssl_verification,
+        ),
+        backend="trio",
+    )
 
 
 if __name__ == "__main__":

src/mcp/client/sse.py

@@ -24,6 +24,7 @@ async def sse_client(
     headers: dict[str, Any] | None = None,
     timeout: float = 5,
     sse_read_timeout: float = 60 * 5,
+    verify_ssl: bool = True,
 ):
     """
     Client transport for SSE.
@@ -43,7 +44,7 @@ async def sse_client(
     async with anyio.create_task_group() as tg:
         try:
             logger.info(f"Connecting to SSE endpoint: {remove_request_params(url)}")
-            async with httpx.AsyncClient(headers=headers) as client:
+            async with httpx.AsyncClient(headers=headers, verify=verify_ssl) as client:
                 async with aconnect_sse(
                     client,
                     "GET",