Deep-analyze any viral reel with Claude (/analyze)
Hey, it's Cindy 🌱 You drop a link into Claude and it comes back with the full autopsy: the transcript, the hook formula, the narrative beats with timestamps.
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
The engine is Sandcastles, a social research tool with a Claude plugin (MCP). Three steps: in Sandcastles go to Settings, Connectors, then the MCP section and download the plugin (you need Pro or above, the Starter plan doesn't include it). In the Claude desktop app (not the browser) click Customize, Plugins, Add, Upload Plugin and drag the zip in, then Install the connector it surfaces. Finally click Connectors in the bottom-left nav, hit Connect on Sandcastles and log in once.
💳 Honest pricing: Sandcastles Pro starts around $39/month billed annually and runs on credits (check the displayed cost before approving analysis). My full setup walkthrough with every click 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 the analysis
🖥️ Open Cowork in the Claude desktop app and click + New task.
⌨️ Type /analyze, a space, then paste the video URL (Instagram, TikTok or YouTube Shorts all work).
🎯 Tell it what you want back. This is my version:
🔬 the deep-analysis prompt
/analyze [paste the video URL] Give me the full breakdown: the complete transcript, the performance stats with the outlier score, the hook category and formula, the format and visual layout, the narrative structure as timed beats, and the topic, angle and substance. Then tell me the meta-pattern: plausible explanations supported by observable evidence, clearly separated from causal claims, in a way I could apply to a completely different topic.
what comes back
The autopsy report
One report with the performance metrics (views, engagement, outlier score against the creator's own baseline), the full transcript, a hook breakdown with its formula, the format and why it works, the narrative beats with timestamps, and the underlying meta-pattern. The outlier score is the part I trust most: it tells you whether the video genuinely beat the creator's normal performance or just had a big account behind it.
💡 Pro move: analyze three videos on the same topic from different creators, then ask Claude "what do the three hooks have in common, and what would a fourth version look like for my angle?" That's where the real leverage is, patterns across videos, not one-off breakdowns.