What causes "Core RPC returned an error" in tinyhumansai/openhuman?

Check the core logs around the request — the concrete failure reason is only visible there.

Core RPC returned an error

Error message

Core RPC returned an error

What it means

Thrown by parseQueueEnvelope() when the raw RPC response carries an `error` object but that error has no `message` string — this literal is the fallback. The core (or the RPC transport) reported a failure for provider_surfaces_list_queue, but the error details were lost or the error was an empty object, so the UI substitutes a generic message. The real cause lives in the core's logs.

Solutions

Check the core logs around the request — the concrete failure reason is only visible there.
Restart the core; a failed store init or transient lock often clears on a fresh boot.
If the error envelope is from an older core, update core+app together to align the error shape.
Improve the fallback to include envelope.error.code/stringified error so users see more than the generic text.

Example fix

// before
if (envelope.error) {
  throw new Error(envelope.error.message ?? 'Core RPC returned an error');
}

// after — preserve whatever detail the envelope carried
if (envelope.error) {
  const detail = envelope.error.message ?? envelope.error.code ?? JSON.stringify(envelope.error);
  throw new Error(`provider_surfaces_list_queue failed: ${detail}`);
}

Defensive patterns

Strategy: try-catch

Type guard

function hasErrorMessage(e: unknown): e is { error: { message: string } } {
  return typeof (e as { error?: { message?: unknown } } | null)?.error?.message === 'string';
}

Try / catch

try {
  return await providerSurfacesApi.listQueue();
} catch (e) {
  const msg = e instanceof Error ? e.message : String(e);
  if (msg === 'Core RPC returned an error') {
    // detail was lost — check core logs; retry once after a core health check
    await waitForCoreHealthy();
    return await providerSurfacesApi.listQueue();
  }
  throw e;
}

Prevention

When wrapping envelopes, propagate error.code/description so the generic fallback rarely fires.
Correlate with core logs using a request id when this surfaces in Sentry.
Retry once after confirming core health — transient store init failures clear on restart.

When it happens

Trigger: The core handler returned a JSON-RPC error with a non-string or missing message field; the Tauri relay wrapped a core-side panic/timeout as {error:{}}; an envelope from an older core shape where error details ride a different key (code/description).

Common situations: Core crashed or timed out serving the queue list; version skew changing the error envelope shape; provider-surfaces store not initialized at boot so the handler errors early with a bare error.

Related errors

AI-assisted analysis of tinyhumansai/openhuman@7491200858 (2026-08-17). Data as JSON: /api/errors/480dcc91bc95bab0. Report an issue: GitHub.

Appendix: source

Thrown at app/src/services/api/providerSurfacesApi.ts:18

import type { RespondQueueList } from '../../types/providerSurfaces';
import { callCoreRpc } from '../coreRpcClient';

interface ProviderSurfacesQueueEnvelope {
  data?: RespondQueueList;
  result?: { data?: RespondQueueList };
}

const EMPTY_QUEUE: RespondQueueList = { items: [], count: 0 };

function parseQueueEnvelope(raw: unknown): RespondQueueList {
  if (!raw || typeof raw !== 'object') {
    throw new Error('provider_surfaces_list_queue: unexpected empty response');
  }

  const envelope = raw as ProviderSurfacesQueueEnvelope & { error?: { message?: string } };
  if (envelope.error) {
    throw new Error(envelope.error.message ?? 'Core RPC returned an error');
  }
  const candidate = envelope.result?.data ?? envelope.data;
  if (!candidate || !Array.isArray(candidate.items) || typeof candidate.count !== 'number') {
    return EMPTY_QUEUE;
  }
  return candidate;
}

export const providerSurfacesApi = {
  async listQueue(): Promise<RespondQueueList> {
    const raw = await callCoreRpc<unknown>({ method: 'openhuman.provider_surfaces_list_queue' });
    return parseQueueEnvelope(raw);
  },
};

View on GitHub (pinned to 7491200858)