Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 5 Nov 2026. What's built · Install 0.3.0
jadpo
ReferenceErrors

ErrorsBackground work · rule

subscriber.item_invalid

Subscriber holds an item it doesn't take, gives one twice or leaves out on: or run:.

Area 12, Background work; not declinable; the next step is usually the agent's.

A subscriber holds on:, run: and retry: only:

example
type Note = Text {    max_length: 200}entity Reminder {    id: Uuid    note: Note    sent: Bool    policy: {        create: [Access.authenticated]        read: [Access.system]        update: [Access.system]    }}type ReminderDue = Event {    reminder_id: Reminder.id}action send_reminder(reminder_id: Reminder.id) fails ReminderNotFound -> Unit {    attempt Reminder.update(reminder_id) {        set: {            sent: true        }    }}subscriber send_due {    on: ReminderDue    run: send_reminder(event.reminder_id)    timeout: 5m}
jadpo checkcheck failed: 1 error, 1 file

error timeout isn't something a subscriber holds

--> main.jadpo:32:5

   |32 |     timeout: 5m   |     ^^^^^^^ not a subscriber item
reason
A subscriber names the event it listens for with on: and the action it runs with run:, and may change how it is retried with retry: { attempts: within: }; nothing else.
next
Write on: <Event> and run: <action>(event), once each (agent)
rule
subscriber.item_invalid
help
https://jadpo.dev/docs/errors/subscriber.item_invalid

Markdown for agents: /docs/errors/subscriber.item_invalid.md.Built from Jadpo main at aee2e8f.