Influencer campaign roster board with AI creator briefs

Build me an app my team can run our influencer campaigns out of. It opens on a roster board grouped by campaign, with a column for each stage: Sourced, Vetted, Contacted, Booked, Live and Wrapped. Each creator is a card sitting in exactly one stage column under exactly one campaign, and a coordinator moves a creator forward by dragging their card between columns.

The roster already lives in Google Sheets and it should stay there as the source of truth. On load, read the roster with Google Sheets Get Values, and use Batch Get Values when the board needs several ranges or campaign tabs in a single request. Expect roughly these columns per row: creator name, platform (Instagram or TikTok), handle, campaign, stage, owner, follower count, engagement rate, the date stats were last refreshed, and a brief link. If the workbook is missing the stage, owner, or brief link columns, offer to add them on first run rather than failing.

Every board change writes back to the sheet. Dragging a card to a new stage writes the new stage value for that creator's row with Update Values, and reassigning a card writes the new owner the same way. Adding a creator to a campaign appends a new row with Append Values. Re-read the affected range after each write so the board reflects what is actually stored, and if the row changed underneath you, reload the roster and tell the coordinator instead of silently overwriting someone else's edit.

Each campaign header summarizes that campaign at a glance: total reach across every creator in it, the median engagement rate, and how many creators are still unvetted (sitting in Sourced, or with no stats ever pulled). Compute all three from values already stored in the sheet so that simply opening the board costs nothing.

Clicking a card opens a detail panel showing that creator's HypeAuditor numbers: follower count, engagement rate, audience authenticity, audience geography and age split, and top posts where available. Pull these with Get Instagram Report or Get TikTok Report depending on the creator's platform. This part matters: each report costs one HypeAuditor credit and HypeAuditor caches reports for 365 days, so never fetch on board load. Show the numbers already stored in the sheet with a clear "last refreshed on <date>" line, and only call HypeAuditor when someone explicitly clicks Refresh stats. When a refresh returns, write the fresh numbers and the new refresh date back to that creator's row with Update Values. If HypeAuditor replies that the report is still being generated, keep the panel in a pending state and retry after the wait period it asks for rather than polling faster.

The detail panel also has a Write the brief button that kicks off a background agent for that one creator. The agent takes the creator's latest HypeAuditor report plus the campaign they are on, and drafts a per creator campaign brief covering audience fit (who follows this creator and why that matches this campaign), a suggested posting cadence, and suggested talking points for the creator to hit. It files the brief in Notion using Create a Page under the workspace's briefs page or database, then Append Block Children to fill in each section. When it finishes, it writes the resulting Notion page URL back into that creator's row with Update Values so the card shows a Brief link. While the agent is running, show that card as "Brief in progress" and let the coordinator keep working the rest of the board.

Several coordinators work this board at the same time, so every card carries an assigned owner shown on the card face, with an owner filter at the top of each campaign and an obvious visual treatment for creators nobody owns yet. Owner is stored in the sheet, so it survives reloads and looks the same to everyone viewing the board.