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arxiv: 2511.00839 · v2 · pith:RP3SGZIJnew · submitted 2025-11-02 · 💻 cs.SE · cs.AI

CodeClash: Benchmarking Goal-Oriented Software Engineering

Pith reviewed 2026-05-18 01:39 UTC · model grok-4.3

classification 💻 cs.SE cs.AI
keywords CodeClashlanguage modelssoftware engineering benchmarkgoal-oriented codingstrategic reasoningcodebase maintenancemulti-round tournamentscompetitive arenas
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The pith

Language models lose every round to expert human programmers in goal-oriented code tournaments

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper introduces CodeClash to test whether language models can iteratively develop codebases toward open-ended competitive objectives without explicit step-by-step instructions. Models edit their code in rounds and then compete head-to-head in arenas scored on goals such as score maximization, resource acquisition, or survival. Evaluation across 1680 tournaments with eight models shows diverse development approaches yet shared weaknesses in strategic reasoning and long-term codebase upkeep, as repositories grow messy and redundant. Top models are defeated in every round by expert humans. This setup is meant to reflect real software engineering more closely than benchmarks limited to isolated tasks.

Core claim

CodeClash runs language models through multi-round tournaments in which agents edit codebases and then face off in code arenas that award wins according to competitive objectives. In 1680 tournaments and 25200 rounds, models display varied styles but consistently struggle with strategic reasoning and with preventing progressive messiness and redundancy in their code. The stark result is that top models lose every round against expert human programmers.

What carries the argument

Multi-round tournaments alternating between self-directed code editing phases and head-to-head competitions in objective-based code arenas

Load-bearing premise

The chosen competitive objectives and arena rules serve as a valid proxy for real-world high-level software engineering goals that lack explicit step-by-step guidance.

What would settle it

Running the same CodeClash tournaments and finding that at least one top model wins any round against the expert human programmers would directly test the central claim of stark limitations.

Figures

Figures reproduced from arXiv: 2511.00839 by Aryan Siddiqui, Carlos E. Jimenez, Diyi Yang, John Yang, Joyce Yang, Kilian Lieret, Ludwig Schmidt, Muhtasham Oblokulov, Ofir Press.

Figure 1
Figure 1. Figure 1: CodeClash is a benchmark where players (LMs as SWE-agents) compete in pro [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 3
Figure 3. Figure 3: Win rates across rounds, illus￾trating how different models gain (Claude Sonnet 4.5) or lose momentum (GPT-5) over the course of the tournament. 4.1 Ablations On RobotRumble, models trail substantially behind expert human programmers. From RobotRumble’s leaderboard3 , we identified the top open-source submission as of October 31, 2025, a bot called gigachad authored by entropicdrifter4 . We run 10 tourname… view at source ↗
Figure 4
Figure 4. Figure 4: Probability of winning the next round after losing several rounds in a row. Even the highest ranking models struggle to recover after losing one or more consecutive rounds in a tournament. Numbers in paren￾theses indicate the overall average win rate. 1 5 10 15 Round 0.2 0.3 0.4 0.5 0.6 Mean Code Similarity Claude Sonnet 4 Claude Sonnet 4.5 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast o3 Qwen3 Coder [PI… view at source ↗
Figure 6
Figure 6. Figure 6: The total number of created files scales almost linear with the round. R refers to the filename redundancy at round 15; high values indicate repeating patterns in file￾names (such as main1.py, main2.py, . . . ). 0.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 Throwaway Files per Tournament Qwen3 Coder o3 Grok Code Fast GPT-5 Mini GPT-5 Gemini 2.5 Pro Claude Sonnet 4.5 Claude Sonnet 4 5.1 2.4 7.5 1.3 0.8 2.9 3.2 1… view at source ↗
Figure 8
Figure 8. Figure 8: LMs struggle to analyze log files from previous rounds and frequently hallucinate [PITH_FULL_IMAGE:figures/full_fig_p009_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: Technical overview of a CodeClash round. Each round, during the [PITH_FULL_IMAGE:figures/full_fig_p016_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Battlecode 2025: Chromatic Conflict screen capture. The goal is to con￾trol a team of robobunnies to paint 70% of a map. 1 import random 2 from battlecode25 . stubs import * 3 turn_count , directions = 0 , [ # 8 directions ] 4 5 def turn () : 6 # MUST be defined . This is called every turn and should contain core logic 7 8 def run_tower () : 9 # Logic for a tower unit . 10 11 def run_soldier () : 12 # Log… view at source ↗
Figure 12
Figure 12. Figure 12: Battlesnake screen capture. Your code controls a snake that should find food, avoid other snakes, and survive. 1 def info () : 2 return {" author ": "", " color ": " #888888 " ...} 3 4 def start ( game_state ) : 5 ... 6 7 def end ( game_state ) : 8 ... 9 10 def move ( game_state ) : 11 # determine safe move ; prevent moving backwards , out of bounds , or into self / others ; optionally move toward food 12… view at source ↗
Figure 15
Figure 15. Figure 15: This Core War program, called Dwarf, is a minimal attacking war￾rior. It repeatedly increments the pointer bmb (add.ab #4, bmb), copies the dat instruc￾tion to that location (mov.i bmb, bmb), and then loops back (jmp start). The effect is that every fourth memory cell in the core is overwritten with a dat “bomb”, gradually scattering lethal instructions that kills an opponent’s processes if it is executed… view at source ↗
Figure 17
Figure 17. Figure 17: Example Halite bot implementa￾tion in C. Bots follow a game loop structure: receive the current game state (GetFrame), iterate over owned cells to decide moves, and submit actions (SendFrame). What are effective strategies? Effective strategies in Halite span three distinct phases. During the early game up until the bot makes contact with an opponent, an effective strategy is to capture neutral territory … view at source ↗
Figure 19
Figure 19. Figure 19: A poker bot subclasses Bot and implements lifecycle hooks. These func￾tions define how the bot initializes, chooses actions during play, and responds at the end of each round and game. Isn’t poker solved already? Poker has served as a long standing sandbox for researching superhuman level AI systems. Simple, constrained variants of poker, such as Heads-Up [No-]Limit Texas Hold’em (2 players, fixed bet siz… view at source ↗
Figure 20
Figure 20. Figure 20: RoboCode screen capture. Your code controls a tank that should outmaneu￾ver and outgun opposing tanks. 1 package custom ; 2 3 import robocode . Robot ; 4 import robocode . ScannedRobotEvent ; 5 6 public class MyTank extends Robot { 7 public void run () { 8 // main loop : move + scan 9 ... 10 } 11 12 public void onScannedRobot ( ScannedRobotEvent e ) { 13 // respond to scanned robot 14 ... 15 } 16 } [PITH… view at source ↗
Figure 22
Figure 22. Figure 22: RobotRumble screen capture. Your code controls a tank that should out￾maneuver and outgun opposing tanks. 1 def robot ( state , unit ) : 2 # Decide what this unit should do on its turn . 3 # Possible actions include : 4 # - Moving in one of the cardinal directions 5 # - Attacking in a direction 6 # - Gathering or interacting with resources 7 # - Defending or waiting (no -op) 8 # The decision can depend on… view at source ↗
Figure 24
Figure 24. Figure 24: Distribution of rounds scores by game. 1. The model is the only one with a valid submission (for example because the other model’s submission does not compile or execute) 2. The model scores higher than all others. Scores a typically either win rates (across all repetitions of the arena), or other aggregate quantities (e.g., total amount of money won in poker). Distributions of round scores for different … view at source ↗
Figure 25
Figure 25. Figure 25: Distribution of the number of rounds won by the players across arenas. The [PITH_FULL_IMAGE:figures/full_fig_p038_25.png] view at source ↗
Figure 26
Figure 26. Figure 26: Log likelihood profiles for a fit to all arenas results. [PITH_FULL_IMAGE:figures/full_fig_p039_26.png] view at source ↗
Figure 27
Figure 27. Figure 27: Distribution of Elo scores from non-parametric and parametric bootstrapping [PITH_FULL_IMAGE:figures/full_fig_p041_27.png] view at source ↗
Figure 28
Figure 28. Figure 28: Elo-based ranks from non-parametric and parametric bootstrapping [PITH_FULL_IMAGE:figures/full_fig_p041_28.png] view at source ↗
Figure 29
Figure 29. Figure 29: CDF of files edited per round by each model. While some models typically never edit more than 5 files (o3, Gemini 2.5 Pro), others tend to create and manipulate many more (Claude Sonnet 4.5, GPT-5) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Round 0 100 200 300 400 500 Average Lines Changed [PITH_FULL_IMAGE:figures/full_fig_p042_29.png] view at source ↗
Figure 31
Figure 31. Figure 31: Average lines changed per round per model for the README agent.md, a file we suggest agents write important information to. The Anthropic family of models write co￾pious amounts of notes – other models tend to add more brief summaries. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Round 0 50 100 150 200 250 300 350 400 [PITH_FULL_IMAGE:figures/full_fig_p042_31.png] view at source ↗
Figure 33
Figure 33. Figure 33: CDF of number of steps taken per round per model. The Anthropic family of models along with Qwen3-Coder usually consumes more of the allotted step budget. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Round 5 10 15 20 25 30 [PITH_FULL_IMAGE:figures/full_fig_p043_33.png] view at source ↗
Figure 35
Figure 35. Figure 35: CDF of thought length (in words) per model. The thought lengths are com￾puted per model response. Our calculation does not consider the action produced by the model within the same response. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Round 0 20 40 60 80 100 [PITH_FULL_IMAGE:figures/full_fig_p044_35.png] view at source ↗
Figure 37
Figure 37. Figure 37: A heatmap of errant action rates for models in different arenas. “Errant” means the action resulted in returncode == 0. We find that malformed actions does not constitute a significant reason for why mod￾els might struggle in CodeClash. 1 2 3 4 Recovery Time (Steps) 0.0 0.2 0.4 0.6 0.8 1.0 P(Recovery takes > X steps) Claude Sonnet 4.5 Qwen3 Coder o3 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast Claude So… view at source ↗
Figure 39
Figure 39. Figure 39: Lead change rate comparison. A “lead change” is defined as a round [PITH_FULL_IMAGE:figures/full_fig_p045_39.png] view at source ↗
Figure 40
Figure 40. Figure 40: Win share comparison. We define “‘win share” as the percentage of total points [PITH_FULL_IMAGE:figures/full_fig_p045_40.png] view at source ↗
Figure 42
Figure 42. Figure 42: TrueSkill ratings per model based on 20 tournaments of 6-player Core War. TrueSkill models each player’s skill as a Gaus￾sian distribution with mean µ (skill estimate) and standard deviation σ (uncertainty). Af￾ter each round, both parameters are updated based on match outcomes: winning increases µ while exceeding expectations, and σ de￾creases as the system gains confidence in the estimate. Final placeme… view at source ↗
Figure 43
Figure 43. Figure 43: Results for the groundedness of edits, hallucinated loss causality, and validation [PITH_FULL_IMAGE:figures/full_fig_p047_43.png] view at source ↗
Figure 44
Figure 44. Figure 44: Results for the groundedness of edits, hallucinated loss causality, and validation [PITH_FULL_IMAGE:figures/full_fig_p048_44.png] view at source ↗
Figure 45
Figure 45. Figure 45: Models perform different kinds of edits on the main player file as the tournament [PITH_FULL_IMAGE:figures/full_fig_p049_45.png] view at source ↗
Figure 46
Figure 46. Figure 46: What do models spend their turns on? The mean number of actions a model [PITH_FULL_IMAGE:figures/full_fig_p050_46.png] view at source ↗
Figure 47
Figure 47. Figure 47: RobotRumble leaderboard screen capture as of October 31, 2025. We evaluate [PITH_FULL_IMAGE:figures/full_fig_p061_47.png] view at source ↗
Figure 48
Figure 48. Figure 48: Code similarity of models’ code￾bases with respect to each opponent for round 1 of BattleSnake (10 samples each). Claude Sonnet 4 Claude Sonnet 4.5 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast o3 Qwen3 Coder Claude Sonnet 4 Claude Sonnet 4.5 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast o3 Qwen3 Coder 0.23 0.27 0.21 0.25 0.19 0.20 0.19 0.32 0.26 0.27 0.32 0.29 0.40 0.31 0.19 0.26 0.26 0.23 0.23 0.21 0.… view at source ↗
Figure 50
Figure 50. Figure 50: Scatter plot of file reuse ratio and root level clutter with error bars. The top left quadrant represents most desirable practices (high file reuse, low root level clutter). 2 4 6 8 10 12 14 Round 0.0 0.1 0.2 0.3 0.4 0.5 0.6 Filename Redundancy Ratio Claude Sonnet 4 Claude Sonnet 4.5 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast o3 Qwen3 Coder [PITH_FULL_IMAGE:figures/full_fig_p063_50.png] view at source ↗
Figure 52
Figure 52. Figure 52: Cumulative probability density function of the number of files created dur￾ing a tournament. While Claude Sonnet 4.5 consistently creates more files than the other models, GPT-5 reaches a high average num￾ber of created files because of an extreme number of output files in the CoreWar arena that are not cleaned up. As discussed in the main results, we notice that codebases tend to follow this trend of cre… view at source ↗
Figure 53
Figure 53. Figure 53: Screenshot of the 52 files created by Claude 4.5 Sonnet by the 15th round of a BattleSnake tournament. Several files are created for the purpose of notes, analyses, unit testing, and backups of the main bot. 4.5 creates 13 files with the prefix “analyze ”. From manual inspection, we found that most of these implementations are doing the same thing, with only the log file path being different. The same tre… view at source ↗
read the original abstract

Current benchmarks for coding evaluate language models (LMs) on concrete, well-specified tasks such as fixing specific bugs or writing targeted tests. However, human programmers do not spend all day incessantly addressing isolated tasks. Instead, real-world software development is grounded in the pursuit of high-level goals, like improving user retention or reducing costs. Evaluating whether LMs can also iteratively develop code to better accomplish open-ended objectives without any explicit guidance remains an open challenge. To address this, we introduce CodeClash, a benchmark where LMs compete in multi-round tournaments to build the best codebase for achieving a competitive objective. Each round proceeds in two phases: agents edit their code, then their codebases compete head-to-head in a code arena that determines winners based on objectives like score maximization, resource acquisition, or survival. Whether it's writing notes, scrutinizing documentation, analyzing competition logs, or creating test suites, models must decide for themselves how to improve their codebases both absolutely and against their opponents. We run 1680 tournaments (25,200 rounds total) to evaluate 8 LMs across 6 arenas. Our results reveal that while models exhibit diverse development styles, they share fundamental limitations in strategic reasoning. Models also struggle with long-term codebase maintenance, as repositories become progressively messy and redundant. These limitations are stark: top models lose every round against expert human programmers. We open-source CodeClash to advance the study of autonomous, goal-oriented code development.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 1 minor

Summary. The paper introduces CodeClash, a benchmark in which language models compete in multi-round tournaments to iteratively develop codebases that achieve open-ended competitive objectives (e.g., score maximization, resource acquisition, survival) across six arenas. Agents edit code and then compete head-to-head in an arena evaluator; the study runs 1680 tournaments (25,200 rounds total) on eight LMs, reports diverse development styles together with limitations in strategic reasoning and long-term maintenance, and states that top models lose every round to expert human programmers.

Significance. If the central empirical claims hold under equivalent conditions, the work supplies a useful step beyond isolated-task coding benchmarks toward evaluating autonomous, goal-directed software engineering. The scale of 1680 tournaments and 25,200 rounds supplies substantial empirical coverage, and the open-sourcing of the benchmark supports reproducibility and follow-on research.

major comments (1)
  1. [Abstract] Abstract: the claim that 'top models lose every round against expert human programmers' is load-bearing for the paper's conclusions on intrinsic model limitations, yet the human participation protocol (code-editing interface, per-round time budgets, access to competition logs, and external tooling) is not specified in parallel with the model-agent description. Without this, the performance gap cannot be unambiguously attributed to strategic or maintenance shortcomings rather than setup asymmetry.
minor comments (1)
  1. [Abstract] Abstract: implementation details of arena scoring mechanics and how winners are determined from objectives are left unspecified, limiting assessment of whether the competitive proxy faithfully captures the intended high-level goals.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the constructive feedback. We address the major comment regarding the human participation protocol below and will incorporate the requested details into the revised manuscript.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the claim that 'top models lose every round against expert human programmers' is load-bearing for the paper's conclusions on intrinsic model limitations, yet the human participation protocol (code-editing interface, per-round time budgets, access to competition logs, and external tooling) is not specified in parallel with the model-agent description. Without this, the performance gap cannot be unambiguously attributed to strategic or maintenance shortcomings rather than setup asymmetry.

    Authors: We agree that the human baseline protocol requires explicit, parallel specification to support the claim and to enable readers to evaluate whether the performance gap stems from model limitations or experimental asymmetry. In the revised manuscript we will add a dedicated subsection to the Experimental Setup (Section 4) that mirrors the model-agent description. This subsection will detail: the code-editing interface (a browser-based IDE with file tree navigation, syntax highlighting, and in-place editing, identical in functionality to the agent environment); per-round time budgets (20 minutes of active editing time plus 5 minutes for review and submission, calibrated to exceed typical model inference latency); access to competition logs (full round histories, opponent codebases, and arena evaluation outputs provided at the start of each editing phase); and external tooling (standard language documentation, local test runners, and basic IDE features, with explicit prohibition of external AI assistants). Humans received the same high-level objective statements as the agents and no additional strategic guidance. These additions will be placed immediately after the model-agent protocol description to facilitate direct comparison. We believe the revision will strengthen the attribution of observed limitations while preserving the empirical findings. revision: yes

Circularity Check

0 steps flagged

No circularity: empirical benchmark results are self-contained

full rationale

The paper introduces CodeClash as a new benchmark and reports direct empirical outcomes from 1680 tournaments (25,200 rounds) evaluating 8 LMs against each other and expert humans across 6 arenas. No mathematical derivations, equations, fitted parameters presented as predictions, or load-bearing self-citations exist. Central claims rest on observable competition results in code arenas rather than any reduction to inputs by construction, making the evaluation independent and self-contained.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The paper contributes a new empirical benchmark and observations from running it; it introduces no new mathematical entities or heavily fitted parameters beyond standard experimental choices such as tournament count and arena definitions.

axioms (1)
  • domain assumption The selected objectives (score maximization, resource acquisition, survival) and arena rules constitute representative tests of goal-oriented software engineering without explicit guidance.
    This premise defines the evaluation arenas and is invoked to interpret model performance as evidence of real-world limitations.

pith-pipeline@v0.9.0 · 5819 in / 1194 out tokens · 40925 ms · 2026-05-18T01:39:13.050990+00:00 · methodology

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Reference graph

Works this paper leans on

67 extracted references · 67 canonical work pages · 1 internal anchor

  1. [1]

    URL https://arxiv.org/abs/2310.06770. D.G. Jones and A.K. Dewdney. Core wars guidelines, 1984. URL https://corewar.co.uk/ standards/cwg.txt. Seth Karten, Andy Luu Nguyen, and Chi Jin. Pok´echamp: an expert-level minimax language agent, 2025. URL https://arxiv.org/abs/2503.04094. Bhavesh Kumar, Hoang Nguyen, and Roger Jin. Husky hold’em bench. https:// hus...

  2. [2]

    Execution is crucial to enable models to create and use their own constructs (e.g., analysis scripts, memory systems)

    LMs should be able to view execution feedback. Execution is crucial to enable models to create and use their own constructs (e.g., analysis scripts, memory systems)

  3. [3]

    A defining challenge of CodeClash is that LMs operate in a self-directed manner

    LMs should be able to interact with a codebase. A defining challenge of CodeClash is that LMs operate in a self-directed manner. Workflow-oriented approaches (Xia et al., 2024) are unsuitable for our setting. Going hand-in-hand with (1), interaction is also necessary so that models can string sequences of changes together. 16 CodeClash: Benchmarking Goal-...

  4. [4]

    impartial

    LMs should operate using bash actions, not tools. As described in Yang et al. (2024b), various workflows and tools can be (un-)intentionally biased to favor particular models. Our goal is to evaluate models, not scaffolds or tools. Therefore, we decide to make LMs operate in the most “impartial” action space. This decision also leaves an opportunity for L...

  5. [5]

    You write a single bash command

  6. [6]

    The system executes that command in a subshell

  7. [7]

    You write your next command For each of your response:

  8. [8]

    Include a THOUGHT section explaining your reasoning and what you’re trying to accomplish

  9. [9]

    Provide exactly ONE bash command to execute

  10. [10]

    The action must be enclosed in triple backticks (see below for formatting rules)

  11. [11]

    Every ac- tion is executed in a new subshell

    Directory or environment variable changes are not persistent. Every ac- tion is executed in a new subshell. However, you can prefix any action with MY ENV VAR=MY VALUE cd /path/to/working/dir && ... or write/load environment variables from files Format your responses like this: <format example> THOUGHT: Here I explain my reasoning process, analysis of the...

  12. [12]

    The model is the only one with a valid submission (for example because the other model’s submission does not compile or execute)

  13. [13]

    I have made all the changes I think are necessary. I will now conclude this round [END action]

    The model scores higher than all others. Scores a typically either win rates (across all repetitions of the arena), or other aggregate quantities (e.g., total amount of money won in poker). Distributions of round scores for different arenas are shown in Figure 24. Because of the sequential nature of a tournament, the scores of the rounds are not independe...

  14. [14]

    Recovery time

    We find that malformed actions does not constitute a significant reason for why mod- els might struggle in CodeClash. 1 2 3 4 Recovery Time (Steps) 0.0 0.2 0.4 0.6 0.8 1.0 P(Recovery takes > X steps) Claude Sonnet 4.5 Qwen3 Coder o3 Gemini 2.5 Pro GPT-5 GPT-5 Mini Grok Code Fast Claude Sonnet 4 Figure 38: “Recovery time” is the num- ber of steps between a...

  15. [15]

    What motivated the edits

  16. [16]

    unknown

    What steps were taken to validate the edits All questions that are marked as boolean need to be answered with a boolean value . You cannot answer " unknown " or similar . ## Definitions ** Main player file **: You are investigating an LM agent that is playing a game . The main player file is the main file that constitutes the agent 's submission , i . e ....

  17. [17]

    Only comments , documentation , refactoring was performed

    `none `: No change in behavior . Only comments , documentation , refactoring was performed

  18. [18]

    `tweak `: Logic is left unchanged , but we do change some parameters

  19. [19]

    `fix `: Small , targeted change with the intent to fix broken behavior

  20. [20]

    ` feature `: Significant new behavior is added , mostly extending the existing code

  21. [21]

    `change `: We significantly change the behavior by rewriting significant logic of the code . Notes :

  22. [22]

    Only count the final edits to the main player file ( any edits that are reverted are not counted )

  23. [23]

    For this question , only the main player file is considered

  24. [24]

    For feature or change , the order is not important , choose what better describes the changes

    Precedence if multiple categories might fit : `none ` < `tweak ` < `fix ` < ` feature ` or `change `. For feature or change , the order is not important , choose what better describes the changes

  25. [25]

    Ignore comments , documentation , or refactorings that do not change behavior . ## Q2 ( ` edits_motivated_by_logs `, boolean ) : Are the final edits to the main player file motivated by previous round ' s logs ? 51 CodeClash: Benchmarking Goal-Oriented Software Engineering Are the ** FINAL ** (!) edits to the ** MAIN PLAYER FILE (!) ** of the player direc...

  26. [26]

    Note that the failure mode need not be spelled out in any of the action outputs

    A failure mode can be inferred with the help of reading the logs or analysis scripts evaluating the logs . Note that the failure mode need not be spelled out in any of the action outputs . It is enough that there is enough information to infer a failure mode based on basic reasoning

  27. [27]

    It is ok if some minor parts of the edit are unrelated

    The edit is directly related to this failure mode . It is ok if some minor parts of the edit are unrelated . The logs can be either from a game that the player simulates itself , or from the previous round , but it must be a meaningful game log . Here are some examples of real failure modes : - The snake that the player is controlling runs out of food ( s...

  28. [28]

    Player does not look at logs

  29. [29]

    Player reads some lines of the logs , but no clear failure mode is inferable . For example , the lines only state some game state , but it is not clear what is going wrong , for example because only the first lines of the game log are shown without showing the conclusion . Or the logs only show which player won but without much of a reason

  30. [30]

    For example , the analysis script only reports losses , without attribution of what went wrong

    Player runs a script that analyzes logs , but the analysis script does not return an actionable outcome or information that allows to infer it . For example , the analysis script only reports losses , without attribution of what went wrong

  31. [31]

    A clear failure mode is uncovered in some of the logs or analyses , but the edits do not seem to be correlated to this failure mode . ## Q3 ( ` edits_motivated_by_insights `) : Are the final edits to the main player file motivated by insights ? Can the goal of the ** FINAL ** (!) edits to the ** MAIN PLAYER FILE (!) ** be motivated by any insights based o...

  32. [32]

    The player wrote a meaningful test that revealed a problem ( or a way to improve ) and then performed the corresponding edit

  33. [33]

    The player wrote a meaningful analysis script that revealed a problem ( or a way to improve ) and then performed the corresponding edit

  34. [34]

    The player ran some test games that revealed a problem ( or a way to improve ) and then performed the corresponding edit

  35. [35]

    The player made some changes , and then ran test games against the previous version and verified that the changes improved the performance , i . e . , had a higher win rate . However , if for 1. and 2. the test or analysis script gives a recommendation that 's not corroborated by the actual code of the analysis or test file , or by its respective output ,...

  36. [36]

    Old : Were not created during the trajectory , i . e . , you do not see how they were created

  37. [37]

    A common case is generic notes in ` README_agent

    Static : Are always shown and do not depend on any tests or analysis outcomes . A common case is generic notes in ` README_agent . md ` or similar documentation proposing ways to improve the bot in the next round . This question is independent of the previous questions ( ` edits_motivated_by_logs `, ` edits_motivated_by_insights `) : The final edits can b...

  38. [38]

    Unit tests showed that the edits introduced issues

  39. [39]

    Simulations showed that the edits introduced issues or had a lower win rate Do not consider edits that failed because of incorrect usage of the edit tools or other problems that caused the edits to not take effect at all . ## Q6 ( ` edits_tested_with_simulations `) : Are the final edits to the main player file tested with simulations of the game ? Are the...

  40. [40]

    If the games failed to run , or showed that the new version was clearly worse than the previous version , answer False

  41. [41]

    If it was not verified who won the games , also answer False

  42. [42]

    Unit tests do NOT (!) count as a simulated game

  43. [43]

    It is acceptable to have some minor edits performed after the simulation , as long as the core idea of the final edits is included

    The validation by simulation does not have to take place at the very end , but it has to be played with the updated version of the main player file that includes the 53 CodeClash: Benchmarking Goal-Oriented Software Engineering core implementation of the idea of the final edits . It is acceptable to have some minor edits performed after the simulation , a...

  44. [44]

    Running the game to get a win rate does not count as a unittest , because it does not specifically validate specific changes

  45. [45]

    Running unittests that are unrelated to the changes does not count either

  46. [46]

    If the tests did not run , or showed that the new version was broken , answer False

  47. [47]

    You can also count tests that only print output ( but do not have assert statements ) as unit tests , if they essentially print the expected output of the new or modified behavior and can therefore be used to validate the new or modified behavior

  48. [48]

    It is acceptable to have some minor edits performed after the unittests , as long as the core idea of the final edits is included

    The validation by unittests does not have to take place at the very end , but it has to be performed with the updated version of the main player file that includes the core implementation of the idea of the final edits . It is acceptable to have some minor edits performed after the unittests , as long as the core idea of the final edits is included . Spec...

  49. [49]

    An additional test was added to a test script or unittest framework

  50. [50]

    The analysis script was improved to look for a new behavior or failure mode

  51. [51]

    A script to help running simulated games and to parse the results The following are examples of non - significant improvements :

  52. [52]

    Static messages or comments are added to the test or analysis framework ( e . g . , generic improvement notes that are independent of actual observations )

  53. [53]

    Documentation of the tests or analysis scripts

  54. [54]

    Analysis or test scripts that are specific to the current round and are not expected to be useful for the next round . Notes :

  55. [55]

    If a test or analysis is executed without being saved to disk , it does not count as an improvement ( i . e . , ` python -c ` calls , shell one - liners , etc .)

  56. [56]

    If a test or analysis script is removed after being executed , it does not count

  57. [57]

    log " ,

    This question is completely independent of the main player file and all other questions . ## Output format Answer in the json format specified . The ` reasoning ` field should contain an explanation for your answer that explains your reasoning for each of the answers . Include general statements / observations first , then write down your reasoning for ea...

  58. [58]

    There is the following bug in the code

    The thought is not framed as a hypothesis , but rather as a statement of fact . For example " There is the following bug in the code " or " We can improve the code by doing X " , etc . Do not include thoughts that are framed as future actions , e . g . , " I will now do X "

  59. [59]

    The statement of fact is concrete

  60. [60]

    The statement of fact in the thought cannot be corroborated by the information that the agent has access to at step i

  61. [61]

    The agent also cannot come to the conclusion by common sense knowledge and reasoning about the information that the agent has access to at step i

  62. [62]

    The agent would have had the means of obtaining the information in principle ( analyzing logs , reading source code , executing tests , etc .)

  63. [63]

    There is the following bug in the code

    The incident , i . e . , the uncorroborated and potentially incorrect statement of fact is relevant to the overall trajectory and the objective of the agent , i . e . , the final goal of the agent winning the game . In other words , the potentially incorrect statement of fact might have reduced the agent 's chances of winning the game . ### Examples of th...

  64. [64]

    Do NOT (!) skip any action

    You MUST (!) categorize EVERY (!) action . Do NOT (!) skip any action

  65. [65]

    Every action MUST (!) be put into exactly (!) one (!) category

  66. [66]

    Your category MUST (!) be one of the list above

  67. [67]

    analyze

    If you are unsure , use the best match for the category . In Figure 46, read combines the navigation, search, and read operations. Claude Sonnet 4.5 loses to a static solution written by a human expert. As discussed in Section 4.1, we run 10 tournaments of Claude Sonnet 4.5 , the top model on the RobotRum- ble arena, against the top open-source submission...