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

ErrorsHTTP · rule

route.output_mismatch

Route output is not exactly what it runs returns.

Area 7, HTTP; not declinable; the next step is usually the agent's.

output: is exactly what the route runs returns:

example
type Memo = Text {    max_length: 200}type MemoId = Uuid {}type AddMemo = Input {    text: Memo}type MemoView = Output {    text: Memo}action add_memo(input: AddMemo) -> MemoView {    return MemoView {        text: input.text    }}type MemoSummary = Output {    text: Memo}routes Memos {    prefix: /memos    POST / {        input: AddMemo        output: MemoSummary        run: add_memo(input)    }}
jadpo checkcheck failed: 1 error, 1 file

error POST /memos sends MemoSummary, but add_memo returns MemoView

--> main.jadpo:30:17

   |30 |         output: MemoSummary   |                 ^^^^^^^^^^^ not `MemoView`
reason
A route's output: is exactly what it runs returns, so the route shows its contract and never sends a field its type doesn't declare.
next
Write output: MemoView (agent)
rule
route.output_mismatch
help
https://jadpo.dev/docs/errors/route.output_mismatch

Markdown for agents: /docs/errors/route.output_mismatch.md.Built from Jadpo main at aee2e8f.