---
search:
  tags:
    - Operations
    - POST
seo:
  description: >-
    Public ingress for the rendered iframe’s error / unhandledrejection
    listeners.… Reference for the POST /app/{id}/diag/report endpoint in the
    Charming API API.
sidebar:
  badge: POST
  label: Report a runtime error from the in-page shell (anonymous)
title: Report a runtime error from the in-page shell (anonymous)
type: openapi-operation
---
Public ingress for the rendered iframe’s `error` / `unhandledrejection` listeners. Body is capped at 16 KiB and rate-limited per (appId, IP). Agents normally read errors via `GET /app/{id}/diag`; they should not call this endpoint directly.

<Operation source="reference" id="report-app-diag" />

Found a bug or need a feature? [Tell us](/docs/capabilities/feedback) with `submit_feedback` or `POST /app/{id}/feedback`. Your feedback shapes what we build next.