I Vibe-Coded a Cryptid-Reporting Station on Sanity (and the Workflow Rejects Bigfoot Blurs)

A developer built Cryptid Field Station, a Sanity-based monorepo application that lets hikers report cryptid sightings and routes each report through an AI-plus-human verification workflow, with obvious fabrications auto-rejected and borderline cases queued for human review. The project uses a single transition() function for all write paths, a real-time Ranger triage app built on @sanity/client listen(), and a seeded jackalope report that admits to being taxidermy as a pipeline control sample. The build was prompted end-to-end in the agentic IDE OpenCode, with the developer noting course corrections away from the early-access @sanity/workflow-engine and @sanity/sdk-react in favor of a data-modeled workflow and a custom real-time interface.

This is a submission for the Sanity Challenge, Path Two: Vibe-Code Something Strange https://dev.to/challenges/sanity-2026-09-16 Cryptid Field Station - a field guide where hikers report cryptid sightings, an AI + human workflow verifies them, and rangers triage from a live command center. submitted ? in-review ? verified ? published ; obvious fabrications auto-reject; everything in between waits for a human verification document next to the sighting - one audit trail, two authors agent + human . The control sample is my favorite part: the seed data includes a jackalope report that openly admits to being taxidermy. If the pipeline ever publishes it, the pipeline is broken. It gets rejected. studio/ today npx sanity dev ; the hosted Studio URL lands here right after sanity deploy custom evidence input below Try it: file a sighting at /report lat/lng optional but the weather check loves them , then watch it land in the Ranger Board's submitted lane and move through review. web/ - Next.js 14 guide + workflow API routes /api/sightings , /transition EvidenceGifInput paste a trail-cam video URL, get a preview + capturable 6-frame GIF-strip ranger/ - real-time triage app live Sanity subscription, own UI workflows/sighting-review.ts - the review process as data stages, guards, effects seed/ - 7 cryptids, 12 sightings with mixed fates, idempotent importer IDE: OpenCode agentic, autonomous powered by Muse Spark - prompted end-to-end, no interactive Studio clicking for the build itself. Prompts that worked: "scaffold a monorepo with these four folders and make every app build before touching Sanity" got three green builds in a row ; "every write path goes through one transition function" kept agent + ranger honest ; "reads must work with an empty dataset" the baked-in field cache, which saved the demo before seeding . Prompts that didn't: asking for the App SDK with @sanity/sdk-react from memory - I couldn't pin the exact provider API without docs in hand, so I course-corrected to a real-time custom app on @sanity/client listen with its own UI, which is what the bonus actually asks for "your own interface, instead of another read-only frontend" . The workflow engine went the same way: rather than fight the early-access @sanity/workflow-engine setup, I modeled the process as data status + verification docs, cookbook-mapped in workflows/ , which runs on any plan today. Where it got stuck: an npm cache corruption on esbuild killed the Studio install fixed with --prefer-online retry ; the Vercel CLI hung on update-notifier checks in a non-TTY shell fixed with NO UPDATE NOTIFIER=1 ; a TS slug-shape mismatch between raw seed JSON and the Cryptid type fixed by mapping slug.current at the fallback boundary . Past the Studio: yes to both bonuses. The Ranger app is a custom real-time surface with live updates and approve/reject/publish actions - not Studio, not read-only. The workflow is data: the agent moves drafts forward triage, auto-verify ?90, auto-reject ?20 and the ranger approves through identical transitions, all audit-logged side by side. yy3ugxmv dataset production cryptid classification, danger 1-5, traits, habitat , sighting cryptid ref, geopoint, evidence URL+type, workflow-owned status , cached weather , expedition cryptid/sighting refs for joint field pushes , credibilityScore are readOnly in Studio - the workflow owns them, humans use the board; evidence type drives conditional rendering video player vs image ; the jackalope is debunked by design as a pipeline control. Built autonomously in OpenCode; transcript available on request. Key decision log: monorepo-first, cache-first reads, one-transition-function rule, honest 503s when the write token is absent.