From 57c6ca4a00397db4e5aa3ea013b4c4a6b4b03d70 Mon Sep 17 00:00:00 2001
From: Ryan Malloy <ryan@supported.systems>
Date: Tue, 17 Feb 2026 17:42:21 -0700
Subject: [PATCH] Make get_device_status resilient to individual USB command
 failures

Wrap get_usb_speed, get_serial_number, and get_last_error in try/except
so a STALL on one command returns "unavailable" instead of crashing the
entire status read. Discovered when vendor command 0x07 (get_usb_speed)
STALLs on real hardware despite working firmware version readback.
---
 mcp/skywalker-mcp/src/skywalker_mcp/server.py | 26 ++++++++++++++-----
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/mcp/skywalker-mcp/src/skywalker_mcp/server.py b/mcp/skywalker-mcp/src/skywalker_mcp/server.py
index 53e4a33..d590474 100644
--- a/mcp/skywalker-mcp/src/skywalker_mcp/server.py
+++ b/mcp/skywalker-mcp/src/skywalker_mcp/server.py
@@ -161,16 +161,30 @@ async def get_device_status(ctx: Context) -> dict:
         with bridge.lock:
             fw = bridge._dev.get_fw_version()
             config = bridge._dev.get_config()
-            speed = bridge._dev.get_usb_speed()
-            serial = bridge._dev.get_serial_number()
-            error = bridge._dev.get_last_error()
+            # Some commands may STALL on certain firmware builds; don't let
+            # one failure kill the entire status read.
+            try:
+                speed_raw = bridge._dev.get_usb_speed()
+                speed = {0: "unknown", 1: "Full (12 Mbps)", 2: "High (480 Mbps)"}.get(
+                    speed_raw, f"unknown ({speed_raw})")
+            except Exception:
+                speed = "unavailable"
+            try:
+                serial = bridge._dev.get_serial_number().hex(' ')
+            except Exception:
+                serial = "unavailable"
+            try:
+                error_code = bridge._dev.get_last_error()
+                error = ERROR_NAMES.get(error_code, f"0x{error_code:02X}")
+            except Exception:
+                error = "unavailable"
             return {
                 "firmware": fw,
                 "config_byte": config,
                 "config_bits": {name: is_set for name, is_set in format_config_bits(config)},
-                "usb_speed": {0: "unknown", 1: "Full (12 Mbps)", 2: "High (480 Mbps)"}.get(speed, f"unknown ({speed})"),
-                "serial": serial.hex(' '),
-                "last_error": ERROR_NAMES.get(error, f"0x{error:02X}"),
+                "usb_speed": speed,
+                "serial": serial,
+                "last_error": error,
             }
 
     return await asyncio.to_thread(_read)