Find what's actually working in your niche with Claude (/topic)
Hey, it's Cindy 🌱 This tool shows you what's working in your watchlist over the last 30 days and groups it into specific video ideas, ranked by views.
btw the waitlist for AI System Club is now open! If you're keen on using AI to automate your content, video editing, job search, business or build AI agents, feel free to sign up (only if you want to hehe). Ps. the waitlist gets first dibs:)
the setup, once
Connect Sandcastles to Claude
You need Sandcastles (Pro plan or above) with its Claude plugin installed in the Claude desktop app, plus a watchlist of the creators in your niche built inside the Sandcastles app. Full click-by-click setup is in the research machine guide.
Complete the connection once
Get the account-specific plugin. In Sandcastles, open Settings, then Connectors, then the MCP section and download the plugin ZIP. MCP access requires an eligible paid Sandcastles plan; check the current plan before buying.
Install in Claude Desktop. Open Customize, Plugins, Add, then Upload Plugin. Upload the ZIP. In the plugin page's Connectors area, choose Install, then Add for the prefilled Sandcastles connector.
Authorize your account. Open Customize, Connectors, find Sandcastles (Custom), choose Connect and complete the Sandcastles sign-in. Confirm the connected state before trying the workflow.
Populate a small watchlist. Use /channels-add with a few creator profile URLs and confirm the returned additions. Use /videos-watchlist to fetch a small sample. Ask Claude to list which examples need /analyze, show the proposed credit cost, and wait for your approval before running those analyses. Confirm that transcripts or analysis results exist before asking for topic, hook or format patterns.
Limit permissions and test. Review the connector's tools. Keep approval enabled for paid analysis or changes until you understand the action and credit cost. Ask Claude to list the available Sandcastles tools and read a small sample from your chosen creator or watchlist.
The official Sandcastles setup documents this installation route. Start with a small watchlist and a few analyzed examples. Ask Claude to identify missing inputs and the proposed credit-using analysis before expanding the sample; an empty dataset is not evidence that a niche has no winners.
These slash commands belong to the installed Sandcastles plugin, not native Claude. If a command is unavailable, describe the same request in plain language and ask Claude to use the connected tools. If sign-in fails, check browser pop-up permissions and organization connector restrictions. Do not paste account passwords or API keys into a prompt.
the workflow
Run /topic like you mean it
In Cowork, type /topic and then get specific. The generic version returns generic themes; this version returns idea seeds you can actually film:
🎯 the topics prompt
/topic What are the highest-performing topics in the available analyzed watchlist sample from the last 30 days? State the sample size and missing coverage. Rank them by views and link the individual videos under each topic. When I say topic I don't mean a broad category, I mean the idea seed: cluster videos that are takes on the same core idea, granular enough that I can look at each cluster and decide "should I make this or not". For each cluster, tell me what makes it distinctive and give me 2 to 3 example videos from my watchlist.
what comes back
Your niche, ranked
A ranked list of 3 to 5 themes with total views per theme, the example videos behind each one, and a "your fit" read on whether the topic suits your channel or should be skipped. The granularity ask is the difference between "AI tools" (useless) and "people are winning with 'I replaced this one app with Claude' videos" (filmable tomorrow).
💡 Pro move: run it weekly and keep score. Ask Claude to compare this week's clusters against last week's so you catch a rising idea seed before it peaks, that's the window where making your version still counts as early.