Agent skill · software engineering · nvidia
doca-comch
Use this skill when the user is doing hands-on DOCA Comch work on a host + BlueField pair — bringing up host ↔ DPU PCIe control-plane messaging, picking server (DPU) vs client (host) roles, choosing slow-path send-task / recv-callback vs fast-path producer / consumer, querying max-msg-size or max-clients capabilities, registering connection callbacks, or debugging DOCA_ERROR_* returns from the Comch API. Trigger even when the user does not explicitly mention "DOCA Comch" or "Comm Channel" (renamed in DOCA 2.5) — typical implicit phrasings include "send a control message from host to BlueField over PCIe", "DPU can't see the host representor", "DOCA_ERROR_NOT_PERMITTED on server_create", "DOCA_ERROR_AGAIN on task_send submit", "connect callback never fires", or "stream bulk data from a host driver to a DPU agent". Refuse and route elsewhere for installing DOCA itself, BFB / firmware bring-up, non-Comch DOCA libraries, or deploying Comch apps at scale — those belong to other skills.
Why this skill is useful
Provides specific commands and workflows for managing DOCA Comch channels that the AI wouldn't reliably generate on its own.
What it needs
Requires doca installed locally. About 7k tokens when loaded. Last updated 2026-08-07. 2,816 stars on the source repository.
What this skill does
DOCA Comch Examples "Send a control message from host to BlueField over PCIe." — this is in scope. Pick server (DPU) vs client (host) and stay on the Comch send/recv path; do not fall back to TCP. "Connect callback never fires." — check role, representor visibility, and the 2.5 rename overlay before rewriting the app as raw verbs. Instructions Follow Loading order below. Open the tasks companion for configure / modify / debug. Open the capabilities companion for slow-path vs fast-path and the 2.5 rename. Do not open every companion file. Where to start: This skill assumes DOCA is already installed and the user is doing hands-on Comch work on a BlueField + host pair with DOCA. Open the tasks companion if the user wants to do something (configure / build / modify / run / test / debug); open the capabilities companion when the question is what can Comch express on this version. If the user has not installed DOCA yet, route to doca-setup/SKILL.md first. If the user is asking "is Comch even on this DOCA" because the docs they read mention doca-comm-channel, route to Version compatibility for the 2.5 rename. Example questions this skill answers well The CLASSES of Comch questions this skill is built to answer, each with one worked example. The agent should treat the class as the load-bearing piece — the worked example is a single instance. "How do I bring up a Comch channel between host and DPU?" — worked example: "server side on the DPU, client side on the host, exchange a first control message". Answered by the role-selection + lifecycle workflow in configure + Capabilities and modes server-vs-client table. "How do I move bulk data over Comch with low CPU?" — worked example: "stream a 64 KiB chunk every 100 µs from the host driver to a DPU agent". Answered by the producer / consumer fast-path described in Capabilities and modes the channel-setup workflow in configure step 4, with the "slow-path vs fast-path" selection rule. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills nvidia/doca-comch