{"record":{"id":"f142f8c8745972d6","repo":"rohitg00/ai-engineering-from-scratch","slug":"peer-name-modern-discovery-omitted-resulttype","errorCode":null,"errorMessage":"{peer.name}: modern discovery omitted resultType","messagePattern":"(.+?): modern discovery omitted resultType","errorType":"exception","errorClass":"RuntimeError","httpStatus":null,"severity":"error","filePath":"phases/13-tools-and-protocols/08-building-an-mcp-client/code/main.py","lineNumber":346,"sourceCode":"            transport=transport,\n            allow_legacy=allow_legacy,\n        )\n\n    @staticmethod\n    def _send(\n        peer: Peer,\n        message: dict[str, Any],\n        timeout_ms: int | None = None,\n    ) -> dict[str, Any] | None:\n        return peer.transport(message, timeout_ms)\n\n    def _mutual_version(self, advertised: list[Any]) -> str | None:\n        common = [version for version in advertised if version in self.supported_modern]\n        return sorted(common, reverse=True)[0] if common else None\n\n    def _activate_modern(self, peer: Peer, result: dict[str, Any], version: str) -> None:\n        if result.get(\"resultType\") != \"complete\":\n            raise RuntimeError(f\"{peer.name}: modern discovery omitted resultType\")\n        peer.era = \"modern\"\n        peer.protocol_version = version\n        peer.capabilities = result.get(\"capabilities\", {})\n        peer.server_info = result.get(\"_meta\", {}).get(SERVER_INFO_KEY, {})\n        peer.available = True\n\n    def _probe_legacy(self, peer: Peer, trigger: str) -> None:\n        if not peer.allow_legacy:\n            raise RuntimeError(\n                f\"{peer.name}: {trigger}; legacy compatibility is not allowlisted\"\n            )\n        request_id = self._new_id()\n        initialize = legacy_request(\n            request_id,\n            \"initialize\",\n            {\n                \"protocolVersion\": self.supported_legacy[0],\n                \"capabilities\": self.client_capabilities.copy(),","sourceCodeStart":328,"sourceCodeEnd":364,"githubUrl":"https://github.com/rohitg00/ai-engineering-from-scratch/blob/39ea8a1c6d0b61f071226eff7ede4d4105fed820/phases/13-tools-and-protocols/08-building-an-mcp-client/code/main.py#L328-L364","documentation":"Error \"{peer.name}: modern discovery omitted resultType\" thrown in rohitg00/ai-engineering-from-scratch.","triggerScenarios":"Thrown at phases/13-tools-and-protocols/08-building-an-mcp-client/code/main.py:346 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"39ea8a1c6d0b61f071226eff7ede4d4105fed820","analyzedAt":"2026-08-26T03:13:46.626Z","schemaVersion":2},"datasetVersion":"2026-08-26T07:17:17.940Z"}