If you're fancying to connect to the debug port on a Pico WH, or the two ports on a Pico Debug Probe or anything else with a JST SH compatible 3-pin connector, this cable will do the trick. It has a 1mm pitch JST SH connector on one end, and 0.1" pitch plug connectors on the other.

Note that the colors we got are somewhat matchy with our '2mm PH' sized  STEMMA cables, so if you are using them for the Debug Probe port, the colors will be as follow:

1. White - SWCLK or UART TX
2. Red - Ground (yeah we know this isn't ideal)
3. Black - SWDIO or UART RX

For more information, visit the JST website for JST PH and JST SH connectors and cables.