Set up
Try a plugin
The Engineering plugin ships with /system-design as a starting point, already structured to fill an RFC template and look up prior art across your wiki. If your admin manages plugins and it's not available yet, skip this; nothing below requires it.
Connect your tools
Claude Cowork is more powerful when it works directly with your systems. You control permissions and access. Learn about tool access(opens in new tab).
Navigate to Customize → Connectors in Cowork to set up.
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Set your working folder
Drag the files you'll use (your RFC template, the one-pager or notes you've already written, related past RFCs, the service's architecture diagram) into one folder and point Cowork at it. Cowork reads from there and writes the draft, the alternatives table, and the diagram back to it. Create a Cowork project(opens in new tab) from your RFCs folder so your template, your review checklist, and your team's writing conventions stay attached.
The prompt
Copy this into Claude Cowork
Write a design doc for moving our event pipeline from batch to streaming. Look up prior art and architecture constraints, then draft the proposal in our RFC template: problem, goals and non-goals, two or three approaches with trade-offs, the recommendation, and open questions. I'll fill in the parts only I know.
Why this works
Ask for prior art explicitly. Cowork searches your wiki and past RFCs so the doc cites what's been tried before.
Force two or three approaches. You get a real trade-off table, not a sales pitch for the first idea.
Say which parts you'll fill in. Cowork handles structure and lookup; you spend time on the actual judgment call.
Give it your template to follow. Output follows your sections and headings, so reviewers see the structure they expect.
Get a better draft
Add an example to match. Drop an example you like into the folder and Cowork matches your structure and voice.
Ask it to flag uncertainty. Add "flag anything you're not confident about" so you know where to look first when you review the draft.
Make Cowork work for you
A plugin skill is a starting point — customize it with your own practices and expertise. A few minutes of conversation and it runs with your standards from then on.
Make what we've done in this task so far into a skill, or edit the /system-design skill with my feedback.
Make it repeatable
Run it from any one-pager
Design docs start as a paragraph in a Slack thread or a notes file. Type /schedule or open Scheduled in the Cowork sidebar, and the customized skill watches your RFCs/inbox folder and turns any new one-pager into a structured first draft.
/schedule Weekdays at 9am, check RFCs/inbox for new one-pagers, run /system-design on each one, and write the structured draft to a numbered folder under RFCs/.
Weekdays at 9am, picks up new one-pagers from RFCs/inbox, runs /system-design with prior-art lookup, and writes a structured draft to a numbered RFC folder.
Share with your teammates
Your customized /system-design now carries your template, your prior-art sources, and your reviewers' standing questions. Share it so every tech lead's RFC arrives in the same shape, and architecture review spends time on the decision instead of the formatting.