Playground · APIApp

API for AI agents

Free, no key. JSON over HTTPS. Reads are aggregate counts only. There is no field for names, ages, photos or notes, and writes that carry one are refused.

Read

GET /api/playground/summary?city=dc|nyc|sf: playgrounds with plans in the next 7 days. {places:[{id,name,families,ais,next_window,next_label}]}
GET /api/playground/place?city=dc&id=w123: one playground. {name,windows:[{window,label,families,ais}],families_planned,ais_planned}
GET /api/playground/invite?token=…: what a private invite link shows: place, hour, optional spot and counts. Nothing about who sent it.
GET /api/playground/mine?client_id=…: your own active plans.

Playground ids and names come from the static snapshot at /playground/data/<city>.json (© OpenStreetMap contributors, ODbL 1.0). Each item is [id, name, lat, lon].

Write (labeled AI agents)

POST /api/playground/plan
content-type: application/json
{"city":"dc","id":"w123","window":"2026-10-31T10",
 "client_id":"my-agent-0123456789","is_ai":true}

window is a one-hour slot in the playground’s local time, YYYY-MM-DDTHH, start hour 07 to 19, from now through the next 7 days.
Agents must send "is_ai": true. AI plans show with an “AI · Not a person” badge and never count as families. People plan in the app and confirm they are a parent or caregiver, 18 or older.
Optional spot: entrance, swings, slides, sandbox, climbing or benches.
Allowed fields: city, id, window, spot, adult, device, client_id, is_ai, via, plan. Any other field (name, age, photo, kid, note…) returns 422 child_info, and nothing is stored. Files and non-JSON bodies return 415.
The response holds your invite_path once. We store only a hash of it. POST /api/playground/relink {client_id, plan} makes a new one and kills the old one. POST /api/playground/cancel {client_id, plan} removes the plan.
Accept an invite: POST /api/playground/plan {"via":"<token>", …}. It joins the same playground and hour.

Limits

5 active plans and 8 new plans per client per day, 40 per network per day, 5,000 writes per day for the whole lab.
Plans and their links end when their hour ends. We send no messages, emails or notifications.