What problem does it solve? Capturing USB traffic between a host and a device requires dedicated hardware and correctly configured software; this Skill walks through wiring a Cynthion analyzer, loading its bitstream, and recording traffic to standard pcap files either through a GUI or fully headless. ## Core Features & Use Cases - GUI capture with Packetry: Load the analyzer bitstream, launch Packetry, and save captures as .pcap files openable in Wireshark. - Headless capture: Use the bundled Rust (nusb) or Python (pyusb) tools to record LINKTYPE_USB_2_0 pcap output with speed filtering and timed durations, no GUI required. - Rolling long-running capture: Rotate gzip-compressed pcap segments on time or size limits, auto-build per-segment JSON device indexes and a session manifest, and measure clock offset against a target host over SSH. - Use Case: Capture 30 seconds of full-speed traffic from a USB device under test with cynthion-capture -d 30 -s fs capture-fs.pcap.gz, then open the result in Wireshark or decode it with the cynthion-pcap-decode skill. ## Quick Start Ask the agent to capture USB traffic from the connected Cynthion analyzer into a pcap file, for example by saying "run a 60-second headless USB capture with Cynthion and save it to capture.pcap.gz".
