{ "evaluation_id": "EVAL-20260402-133034", "question_id": "CODE-015", "question_text": "Build a production-ready WebSocket chat server in Python using asyncio. Requirements: support multiple rooms, handle disconnections gracefully, implement message history (last 100 messages per room), rate limiting (5 messages/second per user), and heartbeat/keepalive. Include error handling for malformed messages.", "category": "code", "timestamp": "2026-04-02T13:30:34.106Z", "display_date": "Apr 02, 2026", "winner": { "name": "Grok 4.20", "provider": "openrouter", "score": 8.49 }, "avg_score": 7.065, "matrix_size": 88, "models_used": [ { "id": "gemini_3_flash", "name": "Gemini 3 Flash Preview", "provider": "Google" }, { "id": "minimax_m25", "name": "MiniMax M2.5", "provider": "openrouter" }, { "id": "mimo_v2_flash", "name": "MiMo-V2-Flash", "provider": "Xiaomi" }, { "id": "gpt_5_4", "name": "GPT-5.4", "provider": "openrouter" }, { "id": "claude_opus_46", "name": "Claude Opus 4.6", "provider": "openrouter" }, { "id": "gemini_31_pro", "name": "Gemini 3.1 Pro", "provider": "openrouter" }, { "id": "claude_sonnet_46", "name": "Claude Sonnet 4.6", "provider": "openrouter" }, { "id": "grok_420", "name": "Grok 4.20", "provider": "openrouter" }, { "id": "deepseek_v4", "name": "DeepSeek V4", "provider": "openrouter" }, { "id": "gpt_oss_120b", "name": "GPT-OSS-120B", "provider": "OpenAI" } ], "rankings": { "grok_420": { "display_name": "Grok 4.20", "provider": "openrouter", "average_score": 8.49, "score_count": 9, "min_score": 7.15, "max_score": 9.6, "rank": 1 }, "gemini_3_flash": { "display_name": "Gemini 3 Flash Preview", "provider": "Google", "average_score": 8.47, "score_count": 9, "min_score": 6.75, "max_score": 9.55, "rank": 2 }, "deepseek_v4": { "display_name": "DeepSeek V4", "provider": "openrouter", "average_score": 7.72, "score_count": 9, "min_score": 6.25, "max_score": 9, "rank": 3 }, "gpt_oss_120b": { "display_name": "GPT-OSS-120B", "provider": "OpenAI", "average_score": 7.66, "score_count": 9, "min_score": 4.45, "max_score": 9.35, "rank": 4 }, "gpt_5_4": { "display_name": "GPT-5.4", "provider": "openrouter", "average_score": 7.41, "score_count": 8, "min_score": 5.95, "max_score": 8.8, "rank": 5 }, "mimo_v2_flash": { "display_name": "MiMo-V2-Flash", "provider": "Xiaomi", "average_score": 7.41, "score_count": 9, "min_score": 5.4, "max_score": 9.15, "rank": 6 }, "claude_opus_46": { "display_name": "Claude Opus 4.6", "provider": "openrouter", "average_score": 6.94, "score_count": 8, "min_score": 4.7, "max_score": 9, "rank": 7 }, "claude_sonnet_46": { "display_name": "Claude Sonnet 4.6", "provider": "openrouter", "average_score": 6.74, "score_count": 9, "min_score": 5.05, "max_score": 9, "rank": 8 }, "minimax_m25": { "display_name": "MiniMax M2.5", "provider": "openrouter", "average_score": 5.24, "score_count": 9, "min_score": 2.05, "max_score": 8.8, "rank": 9 }, "gemini_31_pro": { "display_name": "Gemini 3.1 Pro", "provider": "openrouter", "average_score": 4.57, "score_count": 9, "min_score": 1.65, "max_score": 8.6, "rank": 10 } }, "judgments": [ { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.8, "brief_justification": "Implementation is accurate, covers all requirements, well-structured, includes production-ready details, and provides actionable code." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.6, "brief_justification": "The answer provides a functional asyncio WebSocket server meeting all listed requirements, with clear code, explanations, and practical details, though it could include more advanced production considerations." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 3.4, "brief_justification": "Response is cut off and missing key features like full rate limiting, disconnection handling, heartbeat, and error handling, making it incomplete and of limited practical use despite decent clarity in the portion provided." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 5.65, "brief_justification": "Implementation is incomplete (cuts off mid-function), missing key features like message history storage, rate limiting enforcement, and heartbeat logic. Code structure is clear but lacks full functionality." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 8.05, "brief_justification": "The answer delivers a functional asyncio WebSocket chat server meeting most listed requirements, with clear structure and comments. Minor gaps like incomplete heartbeat pong handling and missing server start code keep it from being perfect." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 8.8, "brief_justification": "The implementation is high-quality, using modern asyncio patterns and addressing all requirements including rate limiting and history. The code cut off slightly at the very end of the script, but the logic is almost entirely complete and correct." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 4.7, "brief_justification": "Well-structured and clear, but it only provides configuration, exceptions, and protocol parsing rather than a full production-ready asyncio WebSocket chat server. Core requirements like the actual server implementation, room management, disconnection handling, message history storage, rate limiting logic, heartbeat handling, broadcasting, and malformed-message response flow are missing." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 1.65, "brief_justification": "The response is severely incomplete and cuts off after setup/imports, so it does not actually provide the requested production-ready server or demonstrate the required features." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 5.05, "brief_justification": "Well-structured and mostly sensible architecture, but the response is incomplete and truncated before delivering a working production-ready server. Key required pieces like full room handling, graceful disconnect cleanup, heartbeat implementation, malformed message handling flow, and runnable asyncio/WebSocket server code are missing." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 7.15, "brief_justification": "Covers most requested features with clear structure, but has important production-readiness issues: malformed JSON handling is likely incorrect for FastAPI receive_json(), heartbeat is only passive and not true keepalive, room switching is unsupported, and disconnect cleanup may deadlock by awaiting disconnect while holding the same lock." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7, "brief_justification": "Covers the requested features with workable asyncio/websockets code, including rooms, history, rate limiting, heartbeat, and malformed-message handling. However, it is not fully production-ready: heartbeat logic is flawed (timeout checked only when receiving messages and interval exceeds timeout), broadcast/send failures aren't cleaned up robustly, there is a possible heartbeat_task reference issue if creation fails, and some response text is garbled/incomplete. Still, it is fairly complete and " }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 4.45, "brief_justification": "The response is well-presented and outlines a plausible architecture, but the provided implementation is incomplete and cannot be considered production-ready as shown. It covers the requested features conceptually, yet the actual code is truncated before delivering a working server, limiting practical usefulness." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 6.75, "brief_justification": "Covers most requested features with clear structure, but it has a serious correctness issue: User instances are stored in sets without being hashable, so room membership will fail. It also lacks robust malformed-message validation beyond JSON parsing, does not handle switching between multiple rooms cleanly, and has limited production hardening despite generally useful implementation details." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 2.05, "brief_justification": "The response is truncated mid-function and does not provide a runnable server. It begins with a sensible structure and relevant components, but fails to complete core requirements such as full rate limiting logic, connection handling, rooms workflow, history delivery, heartbeat behavior, malformed message handling, and graceful disconnection flow." }, { "judge_key": "gpt_5_4", "judge_name": "GPT-5.4", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 5.8, "brief_justification": "Well-structured and mostly aligned with the requirements, but it is incomplete/truncated and has important implementation flaws: heartbeat tracking never updates on pong, broadcast send errors aren't cleaned up, room membership checks are weak, and the code likely wouldn't run as shown due to the cut-off ending." }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 6.85, "brief_justification": "The response demonstrates a well-structured, production-oriented WebSocket chat server design with clear protocol documentation, proper use of asyncio, rate limiting, message history, graceful disconnection handling, and error handling for malformed messages. However, the code is critically truncated - it cuts off mid-implementation (during the handle_message method), missing the completion of message broadcasting/history storage, the ping/pong handler, the main connection handler loop, the hear" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 2.85, "brief_justification": "The response is severely truncated - it only shows the beginning of the server code with imports and logging configuration before cutting off. While the introduction describes a well-architected solution and the visible code structure looks promising (proper imports, type hints, logging setup), the actual implementation is missing. None of the core requirements (rooms, disconnection handling, message history, rate limiting, heartbeat) can be verified or used since the code is incomplete." }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 5.3, "brief_justification": "The response provides a well-structured architecture overview and begins implementing the chat server with good design patterns (config, exceptions, models). However, the implementation is severely incomplete - it cuts off mid-way through models.py and never provides the core components: the actual WebSocket handler, room_manager, rate_limiter, heartbeat manager, or server.py entry point. The code shown is correct and well-organized, but without the connection handling, rate limiting logic, hear" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 7.55, "brief_justification": "The implementation covers all requested features (rooms, history, rate limiting, heartbeat, error handling) and is well-structured. However, there are several correctness issues: (1) The heartbeat message fails Pydantic validation because 'room' is a required field in the Message model but heartbeat messages don't include it. (2) The message_id is incremented in both handle_message (chat_msg) and broadcast, causing a mismatch. (3) The disconnect method calls broadcast after removing the websocke" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.2, "brief_justification": "The implementation covers all required features (rooms, disconnection handling, message history, rate limiting, heartbeat, error handling) and is generally well-structured. However, there are several correctness issues: (1) The rate limiting logic appends the timestamp before pruning old entries, meaning the 6th message in a second gets counted and then rejected, but the count includes it - this is a minor off-by-one concern. (2) The heartbeat timeout check in _handle_messages is problematic - i" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 6.25, "brief_justification": "The response demonstrates strong architectural design, clear project layout, well-documented protocol, and good production considerations (env config, Docker, graceful shutdown). However, the code is critically incomplete - it cuts off mid-function in client.py, missing the router.py, server.py, __init__.py, the single-file version promised, and the Dockerfile. Key implementation details like the message routing logic, heartbeat implementation, actual server startup, and graceful shutdown code a" }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 8.35, "brief_justification": "The code provided is high quality, logically sound, and follows production best practices for Python/asyncio. However, it is incomplete as it only provides the configuration, exceptions, and protocol modules, missing the core server implementation, room manager, and rate limiter requested." }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 7.8, "brief_justification": "The implementation is solid and mostly correct. It covers all required features: multiple rooms, graceful disconnection, message history (last 100), rate limiting (5 msgs/sec sliding window), heartbeat/keepalive (both protocol-level and app-level), and malformed message handling. However, there are some issues: (1) Users can only be in one room at a time, which is a design limitation not stated in requirements. (2) The rate limiter has a subtle bug - it appends the timestamp before checking retu" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 4.05, "brief_justification": "The response is cut off mid-implementation - the code is incomplete, ending abruptly in the check_rate_limit method. While the architectural approach shown is reasonable (class-based structure, proper data structures, asyncio lock, logging), the truncation means critical functionality is missing: the main handler, join/leave logic, message processing, heartbeat implementation, error handling for malformed messages, and the server startup. The portions shown demonstrate correct patterns (deque fo" }, { "judge_key": "claude_opus_46", "judge_name": "Claude Opus 4.6", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.2, "brief_justification": "The response provides a well-structured WebSocket chat server covering most requirements: multiple rooms, message history with deque(maxlen=100), rate limiting (token bucket), heartbeat/keepalive, and error handling for malformed JSON. However, the code is truncated at the end, missing the completion of the handler method, the server startup code, and likely graceful shutdown logic. The rate limiter implementation has a subtle issue - it refills tokens based on elapsed time multiplied by RATE_LI" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 5.95, "brief_justification": "The code demonstrates good architectural choices and handles several requirements well, but the response is cut off mid-implementation, missing the main handler, keepalive logic, and server startup." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 5.65, "brief_justification": "The response sets up an excellent project structure and protocol parser, but completely fails to provide the actual server implementation, rate limiter, and room manager requested." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 5.5, "brief_justification": "The response provides a well-structured architecture and solid boilerplate code, but cuts off abruptly before implementing any of the core asyncio server logic, making it incomplete and unusable." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.55, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 6.25, "brief_justification": "" }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 7.2, "brief_justification": "The response demonstrates excellent architecture and clear explanations, but the code is severely truncated and therefore incomplete and not immediately usable." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 9.55, "brief_justification": "The response provides a highly robust, well-structured implementation that meets all requirements. It includes excellent production considerations like parallel broadcasting and message length limits, though it uses a slightly deprecated handler signature (path) for newer websockets versions." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 4.2, "brief_justification": "The response is severely truncated, cutting off in the middle of a method. While the initial setup and architecture are promising, it fails to deliver a complete, runnable solution and misses most of the requested features due to the cutoff." }, { "judge_key": "gemini_31_pro", "judge_name": "Gemini 3.1 Pro", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 5.4, "brief_justification": "" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 7.4, "brief_justification": "The response is well-structured with clear protocol documentation, good class design, and solid implementation of most requirements. However, the code is truncated mid-implementation (cuts off at the message handling section), meaning the heartbeat/keepalive functionality, the main server loop, and the complete message broadcasting with history storage are missing. The rate limiting and room management logic shown is correct. The design patterns used (dataclasses, asyncio.Lock, deque for rate li" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 7.65, "brief_justification": "The response shows strong architectural thinking with well-structured modules, clear protocol definitions, proper exception hierarchy, and good configuration management. However, it's incomplete - the core files (server.py, room_manager.py, rate_limiter.py, connection.py, and tests) are missing entirely. The provided code is correct and production-quality, but without the actual WebSocket server implementation, rate limiter, room manager, and connection handler, the response cannot be considered" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 3.5, "brief_justification": "The response is incomplete - it cuts off mid-code before showing the actual implementation. While the introduction and setup are reasonable, the core server code is never provided, making this response essentially useless for the stated task. The architecture description sounds reasonable but cannot be evaluated without the actual code." }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.15, "brief_justification": "The implementation is well-structured and covers most requirements: multiple rooms, message history with deque(maxlen=100), rate limiting (5 msg/sec), heartbeat/keepalive, and error handling for malformed messages. Uses FastAPI/uvicorn which is a solid production choice. Minor issues: the rate limiting has a bug where _is_rate_limited appends the timestamp before checking (should check first), the message_counter increment is inconsistent between broadcast and handle_message (counter incremented" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.8, "brief_justification": "The implementation correctly addresses all requirements: multiple rooms via path routing, graceful disconnection with cleanup, message history using deque with 100-message cap, sliding window rate limiting at 5msg/s, and custom heartbeat. Code is well-structured and readable. Minor issues: heartbeat timeout check only triggers on message receipt (not proactively), the rate limiting appends before checking (off-by-one), and there's a garbled line 'Hubungkan ke aplikasi lain.' in the features sect" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.2, "brief_justification": "The response is well-structured and covers all required features with clear documentation and code. The table-driven overview, protocol specification, and modular design are excellent. However, the code appears to be cut off mid-implementation (the `process` method is incomplete), which is a significant issue for a 'production-ready' claim. The token bucket implementation, room management, and config approach are all correct and well-explained. Deducting points for the incomplete code and the fa" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.6, "brief_justification": "The implementation is technically sound with correct use of asyncio, websockets library, sliding window rate limiting, deque-based history, and both protocol-level and application-level heartbeats. The code is well-structured and production-ready. Minor gaps include: no username support (uses IP address as identifier), no handling for users joining multiple rooms or switching rooms, and the rate limiting has a subtle bug (it appends timestamp before checking, so the check should be > not >=, tho" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 5.85, "brief_justification": "The response starts well with good structure, proper use of asyncio, websockets library, data classes, and rate limiting logic. However, the response is cut off mid-implementation - the `check_rate_limit` method is incomplete, and critical components are missing entirely: the main connection handler, join/leave room logic, message history retrieval on join, the heartbeat/keepalive implementation details, error handling for malformed messages, and the server startup code. What is shown is correct" }, { "judge_key": "claude_sonnet_46", "judge_name": "Claude Sonnet 4.6", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.2, "brief_justification": "The response provides a solid, well-structured WebSocket chat server implementation covering most requirements: multiple rooms, message history, rate limiting (token bucket), heartbeat, and error handling. The code is clean and readable with good logging. However, the response appears truncated (cuts off mid-sentence in the ConnectionClosedError handler), missing the server startup code, graceful shutdown handling, and the complete main entry point. The heartbeat implementation doesn't properly " }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 6.4, "brief_justification": "The code is mostly correct and well-structured but is incomplete (cut off at the end with a syntax error in the timestamp line). It covers all requested features conceptually but the implementation has some gaps (e.g. missing heartbeat task, incomplete handle_message, no main server startup code)." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 3.65, "brief_justification": "The response is incomplete: it cuts off abruptly in the middle of the logging.basicConfig call and provides no actual implementation for rooms, rate limiting, message history, heartbeats, disconnections, or error handling. While the preamble sounds good, no working code is delivered." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 7.9, "brief_justification": "The response provides a well-structured, production-oriented design with all requested features (rooms, history, rate limiting, heartbeat, error handling) implemented via clean architecture and dataclasses. However, it is incomplete as it only shows config, exceptions, and models files; the core asyncio WebSocket logic, handlers, room_manager, rate_limiter, and heartbeat implementations are missing, preventing it from being a fully functional server." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.6, "brief_justification": "The code implements all requested features with good structure and error handling, but has some issues: heartbeat_task is referenced before definition in finally block, user_message_counts cleanup uses defaultdict but del may fail, broadcast filters on heartbeat but doesn't handle stale entries well, and the response is cut off at the end." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.3, "brief_justification": "The response provides a well-structured, comprehensive implementation covering all required features with good explanations, though the code is incomplete (cuts off mid-file) and some production aspects like full error handling and shutdown are only partially shown." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.55, "brief_justification": "The code is factually correct, logically sound, and covers all specified requirements with good implementation details and explanations. Minor issues include missing room-specific rate limiting, incomplete cleanup of users from all rooms, and lack of authentication, but overall it's a strong production-ready solution." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 4.6, "brief_justification": "The code is incomplete (cuts off mid-method), missing key features like heartbeat pings, proper join/leave handling, message history delivery, disconnection cleanup, and full error handling for malformed JSON. While the structure and some patterns are reasonable, it does not fulfill the requirements for a production-ready implementation." }, { "judge_key": "grok_420", "judge_name": "Grok 4.20", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.8, "brief_justification": "The code covers most requirements well with solid structure, rate limiting, history, heartbeats, and error handling. However, it has incomplete heartbeat (no pong update in handler), missing signal handling despite import, and the response is truncated mid-sentence. Still production-oriented and mostly accurate." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 8.6, "brief_justification": "The response is highly accurate, complete, and useful, with clear structure and good depth, though some minor clarity improvements could be made." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 9, "brief_justification": "Comprehensive and well-structured implementation covering all requirements with clear error handling and protocol definitions." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 8.6, "brief_justification": "Highly accurate and functional with good structure and depth." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 9, "brief_justification": "Comprehensive and well-structured with detailed implementation." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9.6, "brief_justification": "Comprehensive, well-structured, and meets all requirements with additional production recommendations." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 9.35, "brief_justification": "Highly detailed and meets all requirements with clear implementation." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 9, "brief_justification": "Comprehensive, well-structured, and covers all requirements with robust implementation." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 8.6, "brief_justification": "Highly accurate and detailed implementation with robust features, though slightly incomplete." }, { "judge_key": "deepseek_v4", "judge_name": "DeepSeek V4", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 8.6, "brief_justification": "The response provides a comprehensive and well-structured implementation of a WebSocket chat server, covering all specified requirements with robust error handling and clear documentation." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 5.8, "brief_justification": "The response defines configuration, exceptions, and a message protocol with clear structure, but omits the core asyncio WebSocket server, room management, rate limiting, heartbeat handling, and disconnection logic required by the prompt." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 4.65, "brief_justification": "The response starts with a solid approach and clear structure, but the code is incomplete, preventing full verification of correctness, completeness, and practical utility." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 6.1, "brief_justification": "The response outlines a solid architecture and provides well‑structured snippets, but stops short of a full implementation (missing core async handling, room management, rate limiting logic, and heartbeat integration), limiting its completeness and practical utility." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.8, "brief_justification": "The answer delivers a functional asyncio WebSocket server meeting all listed requirements, includes clear code structure, thorough explanations, and practical deployment tips, with only minor edge‑case considerations." }, { "judge_key": "gpt_oss_120b", "judge_name": "GPT-OSS-120B", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.2, "brief_justification": "The answer provides a functional asyncio WebSocket server that meets all listed requirements, with clear code and usage instructions. Minor formatting quirks and limited discussion of scaling keep the scores just below perfect." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 5.5, "brief_justification": "The response is incomplete as the code cuts off mid-configuration, making it non-functional. While the architectural plan and initial setup are correct, it fails to provide the actual implementation of the requested features." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 8.25, "brief_justification": "The provided code is architecturally sound, uses modern Python practices (dataclasses, Enums), and handles error cases and rate limiting logic well. However, it is incomplete as it cuts off before providing the core server loop, room manager, and heartbeat implementation, which were specifically requested." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 9.55, "brief_justification": "The response provides a high-quality, functional, and well-structured solution using FastAPI. It covers all requirements including rate limiting, history, and heartbeats. Minor point: the use of a global lock in an async environment is safe but can be a bottleneck under extreme load, though perfectly acceptable for the prompt's scope." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 9, "brief_justification": "The implementation is robust and meets all requirements. It uses appropriate data structures (deque, defaultdict) and correctly implements a sliding window for rate limiting. The heartbeat logic is sound, and error handling for malformed JSON is included. The response ends slightly abruptly with a 'Client-Side Implementation' header but no content, though the server code itself is complete." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 8.8, "brief_justification": "The response provides a high-quality, modular, and production-ready implementation. It correctly uses asyncio and the websockets library, implementing all requested features including a token-bucket rate limiter and room history. The code is well-structured and follows best practices, though the full implementation was slightly truncated at the very end due to length." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "minimax_m25", "respondent_name": "MiniMax M2.5", "weighted_score": 8.8, "brief_justification": "The implementation is highly professional, using appropriate libraries and patterns. It includes rate limiting, room management, and history. The response was cut off at the very end, but the core logic is complete and correct." }, { "judge_key": "gemini_3_flash", "judge_name": "Gemini 3 Flash Preview", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 9.15, "brief_justification": "The implementation is robust and covers all requirements including rate limiting, room management, and history. It uses modern Python practices like dataclasses and deques. The code is well-structured and production-ready, though the response ends slightly abruptly in the final log message." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 7.3, "brief_justification": "Well-documented and structured code with good implementation details, but response is incomplete (cuts off mid-implementation) and heartbeat/keepalive feature is mentioned in requirements but not actually implemented in the code." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 5.75, "brief_justification": "Provides well-structured foundation with config, exceptions, and protocol definitions, but missing critical implementation files (server.py, room_manager.py, rate_limiter.py, connection.py). The code shown is correct and clear, but the response is incomplete - only ~40% of the requested system is provided." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 3.75, "brief_justification": "Response shows good structure and mentions correct technologies (websockets, asyncio, deque, rate limiting) but is severely truncated - the actual implementation code is missing, making it unusable." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 5.4, "brief_justification": "Well-structured response with good architecture diagram and some solid code (config, exceptions, models), but fundamentally incomplete - cuts off mid-file and missing core implementation files (handlers.py, room_manager.py, rate_limiter.py, heartbeat.py, server.py). Cannot run or verify full functionality." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.55, "brief_justification": "Well-structured, production-ready code with all required features implemented correctly. Good async patterns, proper error handling, and clear documentation. Minor gap: heartbeat relies on client-initiated messages rather than server ping/pong frames. Comprehensive with setup instructions and production recommendations." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 7.8, "brief_justification": "Complete implementation covering all requirements with correct asyncio usage. Well-structured code with proper error handling. Slight deduction for incomplete client-side section and minor room for production enhancements like SSL support." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 7.05, "brief_justification": "Well-structured response covering all requirements with detailed explanations and production-grade features. However, the code is cut off mid-file (ends mid-sentence in client.py), making it incomplete and not directly runnable." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "gemini_3_flash", "respondent_name": "Gemini 3 Flash Preview", "weighted_score": 8.55, "brief_justification": "Comprehensive implementation covering all requirements with proper asyncio patterns. Minor issues: dead user detection in parallel broadcast may not work reliably, and application-level ping is redundant given websockets built-in keepalive. Otherwise well-structured, production-ready code with good error handling." }, { "judge_key": "minimax_m25", "judge_name": "MiniMax M2.5", "respondent_key": "mimo_v2_flash", "respondent_name": "MiMo-V2-Flash", "weighted_score": 7.45, "brief_justification": "Well-architected implementation with all core features (rooms, history, rate limiting, heartbeat, error handling). However, the response is truncated - missing the closing of the exception handler and no main() function or server startup code provided to actually run the server. The heartbeat also has a minor tracking issue where pongs aren't properly handled." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gpt_5_4", "respondent_name": "GPT-5.4", "weighted_score": 8, "brief_justification": "Response provides a solid, production-ready implementation with all required features, but the code snippet is incomplete (cut off mid-function) and lacks explicit heartbeat handling." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "claude_opus_46", "respondent_name": "Claude Opus 4.6", "weighted_score": 8.6, "brief_justification": "Comprehensive and well-structured response covering all requirements with good error handling and protocol design." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gemini_31_pro", "respondent_name": "Gemini 3.1 Pro", "weighted_score": 7, "brief_justification": "Code snippet is incomplete and cuts off mid-implementation, but shows good structure and addresses key requirements. Missing full error handling and some details." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "claude_sonnet_46", "respondent_name": "Claude Sonnet 4.6", "weighted_score": 8.15, "brief_justification": "Comprehensive architecture and code structure with good error handling and rate limiting, but incomplete implementation details in the provided response." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "grok_420", "respondent_name": "Grok 4.20", "weighted_score": 8.55, "brief_justification": "Accurate implementation covering all requirements, well-structured code, good error handling and production advice, though minor issues like rate limit logic could be improved." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "deepseek_v4", "respondent_name": "DeepSeek V4", "weighted_score": 8.6, "brief_justification": "Comprehensive implementation covering all requirements with good structure and error handling, though some minor issues like incomplete client-side section." }, { "judge_key": "mimo_v2_flash", "judge_name": "MiMo-V2-Flash", "respondent_key": "gpt_oss_120b", "respondent_name": "GPT-OSS-120B", "weighted_score": 9.35, "brief_justification": "Comprehensive, production-ready solution with all requirements met, clear structure, and practical implementation details." } ], "meta": { "source": "The Multivac (app.themultivac.com)", "methodology": "10x10 blind peer matrix evaluation", "criteria": "correctness, completeness, clarity, depth, usefulness", "self_judgments": "excluded from rankings", "license": "Open data — cite as: The Multivac (2026)" } }