can1357/oh-my-pi · error

Unsupported wire type ${wireType} in Struct

Error message

Unsupported wire type ${wireType} in Struct

What it means

The manual protobuf decoder in the discovery layer throws this when it reads a field tag whose 3-bit wire type is not one of the wire types the decoder knows how to skip/parse (isWireType fails). Struct is a google.protobuf.Struct decoded by hand; an unknown wire type means the bytes do not match the expected protobuf encoding. This guards against corrupt or unexpectedly encoded payloads.

Source

Thrown at packages/catalog/src/discovery/protobuf.ts:1029

				assertWireType(wireType, 2);
				value = readJsonList(new Reader(reader.bytes()));
				break;
			default:
				reader.skip(wireType);
				break;
		}
	}
	return value;
}

function readJsonStruct(reader: Reader): { [key: string]: JsonValue } {
	const output: { [key: string]: JsonValue } = {};
	while (reader.pos < reader.len) {
		const tag = reader.uint32();
		const fieldNumber = tag >>> 3;
		const wireType = tag & 7;
		if (!isWireType(wireType)) {
			throw new Error(`Unsupported wire type ${wireType} in Struct`);
		}
		if (fieldNumber === 1) {
			assertWireType(wireType, 2);
			const entryReader = new Reader(reader.bytes());
			let entryKey = "";
			let entryVal: JsonValue = null;
			while (entryReader.pos < entryReader.len) {
				const entryTag = entryReader.uint32();
				const entryNo = entryTag >>> 3;
				const entryWire = entryTag & 7;
				if (entryNo === 1) {
					entryKey = entryReader.string();
				} else if (entryNo === 2) {
					entryVal = readJsonValue(new Reader(entryReader.bytes()));
				} else if (isWireType(entryWire)) {
					entryReader.skip(entryWire);
				}
			}

View on GitHub (pinned to 9690622007)

Solutions

1. Inspect the raw response body for corruption or HTML/error pages injected into a binary protobuf stream
2. Verify the request is hitting the correct protobuf endpoint (not a JSON or HTML error page)
3. Update the catalog package; the decoder may not support a wire type the provider newly emits
4. Capture the payload and file a bug with the truncated hex dump

try {
  const struct = decodeStruct(bytes);
} catch (err) {
  if (err instanceof Error && err.message.startsWith("Unsupported wire type")) {
    logger.warn("Malformed protobuf Struct payload; refetching", { cause: err });
    return refetch();
  }
  throw err;
}

When it happens

Trigger: Decoding a google.protobuf.Struct (e.g. from a discovery/catalog API response) whose bytes contain a field tag with wire type outside the supported set (0-5 are valid; anything else, e.g. 6 or 7, is malformed).

Common situations: Corrupted or truncated gRPC/protobuf responses, a proxy mangling binary bodies, or a new upstream encoding the decoder doesn't recognize.

Related errors

• Unsupported wire type ${wireType} in ListValue
• Unsupported protobuf wire type ${wireType} at byte ${reader.
• Unsupported wire type ${entryWireType} in map entry
• invalid byte sequence: {:02x?}
• Unknown oneof field ${fieldNumber}

AI-assisted analysis of can1357/oh-my-pi@9690622007 (2026-08-31). Data as JSON: /api/errors/caae77d1dac77846. Report an issue: GitHub.