Agent Benchmarks Beyond Task Completion: Measuring What Matters for Deployed Systems

Andres G. and the PaxLabs Research Team PaxLabs Inc. Correspondence: legal@paxeer.app

ABSTRACT

The rapid proliferation of autonomous AI agents has driven demand for standardized benchmarks that can compare systems on equal footing. Current benchmarks, including GAIA, SWE-bench, AgentBench, WebArena, OSWorld, tau-bench, and MLE-bench, predominantly measure task completion rate as their primary metric. While task completion is a necessary condition for a useful agent, we argue that it is not sufficient for evaluating systems intended for real-world deployment. In this paper, we formalize this insufficiency result and propose a seven-dimension evaluation framework that adds intent fidelity, reproducibility, repair cost, replay integrity, safety gate correctness, and audit completeness to the evaluation criteria. We provide formal definitions, scoring rubrics, and measurement protocols for each dimension. We demonstrate through a theoretical analysis that single-run evaluation of stochastic agents is fundamentally misleading, and we specify a multi-run protocol that addresses this limitation. Our framework is designed to be orthogonal to existing benchmarks: any task suite can be re-evaluated under our protocol without modification to the tasks themselves.

Index Terms: agent evaluation, benchmark design, AI safety, deployed

systems, reproducibility, audit trails, intent fidelity

I. INTRODUCTION

The past two years have seen a dramatic expansion in the capabilities of AI agents. Systems built on large language models (LLMs) can now write software, navigate web interfaces, manage files, and coordinate multi-step workflows with increasing competence [1], [2]. This progress has been accompanied by an equally impressive effort to measure it. Benchmarks such as GAIA [3], SWE-bench [4], AgentBench [5], WebArena [6], OSWorld [7], tau-bench [8], and MLE-bench [9] have provided the research community with standardized tasks and leaderboards that enable direct comparison between systems.

Yet a growing number of practitioners report a persistent gap between benchmark performance and deployment utility. An agent that scores 70% on SWE-bench may still be unsuitable for production use, not because it fails too often, but because when it fails, it fails in ways that are expensive to diagnose, impossible to reproduce, or unsafe in context. The problem is not that current benchmarks measure the wrong thing; it is that they measure only one thing.

In this paper, we make three contributions. First, we formalize the insufficiency of task completion as an evaluation criterion, showing that it satisfies a necessary but not sufficient condition for deployed agent quality. Second, we propose a seven-dimension evaluation framework that captures the additional properties a deployed agent must satisfy. Third, we provide a concrete implementation specification that allows any existing benchmark to be re-evaluated under our protocol without modifying the underlying tasks.

Our framework is motivated by a simple observation: a benchmark is a proxy for deployment fitness, and a proxy with a single dimension will inevitably be gamed or will fail to predict real-world performance. By expanding the evaluation to seven dimensions, we aim to close the gap between leaderboard scores and production readiness.

II. BACKGROUND

We begin by reviewing the current benchmark ecosystem, focusing on the tasks, evaluation criteria, and known limitations of the major benchmarks in use today.

A. GAIA

GAIA (General AI Assistants) [3] is a benchmark of 466 real-world questions that require multi-step reasoning, web browsing, and tool use. Tasks are categorized into three difficulty levels. Evaluation is binary: the agent either produces the correct final answer or it does not. GAIA's design philosophy emphasizes real-world applicability, but its evaluation metric (accuracy) does not distinguish between an agent that answered correctly on the first try and one that required 47 attempts.

B. SWE-bench

SWE-bench [4] evaluates an agent's ability to resolve GitHub issues by generating code patches. The benchmark draws from real open-source repositories. The primary metric is the percentage of issues for which the agent's patch passes the repository's test suite. SWE-bench has been widely adopted, and its variant SWE-bench Verified [10] addresses some quality concerns in the original dataset. However, passing tests is a necessary but not sufficient condition for code correctness, and the benchmark does not measure whether the agent introduced regressions, modified unrelated code, or violated project conventions.

C. AgentBench

AgentBench [5] provides a multi-environment evaluation across eight distinct environments, including operating systems, databases, and knowledge graphs. Its strength lies in breadth: it measures agent performance across heterogeneous settings. The evaluation, however, remains task-completion-centric, with each environment defining its own success criteria. AgentBench does not measure the consistency of performance across repeated trials on the same task.

D. WebArena

WebArena [6] evaluates web-based agent tasks in realistic website environments. Tasks involve navigating complex web interfaces, extracting information, and performing multi-step interactions. WebArena uses functional correctness as its primary metric, meaning the agent's action must produce the correct observable outcome in the web environment. The benchmark acknowledges that web tasks are inherently noisy, but its evaluation protocol does not account for this noise in the scoring.

E. OSWorld

OSWorld [7] extends agent evaluation to full operating system environments, requiring agents to interact with desktop applications, file systems, and system utilities. Tasks are grounded in real-world desktop workflows. OSWorld uses script-based evaluation that checks whether the system state matches expected outcomes after the agent completes its work. Like the other benchmarks, it reports a single-run accuracy.

F. tau-bench

tau-bench [8] evaluates language model agents on tasks that require multi-turn interaction with simulated users and tools. The benchmark focuses on the agent's ability to follow complex, multi-step instructions while maintaining context across turns. tau-bench introduces the concept of "task pass rate" but does not decompose failures into categories such as intent misunderstanding versus execution error.

G. MLE-bench

MLE-bench [9] measures an agent's ability to perform machine learning engineering tasks, including data preprocessing, model training, and submission to Kaggle competitions. The evaluation compares the agent's submission score against human benchmarks. MLE-bench is notable for measuring a quantitative outcome (competition score), but it does not assess whether the agent's training pipeline is reproducible, well-documented, or safe to run in a shared environment.

H. Common Limitations

Across these benchmarks, we identify three recurring limitations:

1) Single-run evaluation: Most benchmarks run each task once (or a small, fixed number of times) and report aggregate accuracy. This conflates luck with capability.

2) Outcome-only measurement: The evaluation considers only whether the final state matches the expected state, not how the agent arrived there or what side effects it produced.

3) No deployment properties: None of the benchmarks measure audit completeness, safety gate adherence, or the cost of recovering from failures.

These limitations motivate the framework we present in the following sections.

III. WHY TASK COMPLETION IS INSUFFICIENT

We now formalize the argument that task completion rate, while necessary, is not sufficient for evaluating deployed agent quality.

Definition 1 (Task Completion). Let T be a task drawn from a benchmark distribution D. Let A be an agent. We say A completes T, written C(A, T) = 1, if and only if the final state produced by A executing T satisfies the benchmark's success criterion. The task completion rate of A over D is:

R(A, D) = E_{T ~ D}[C(A, T)]

Definition 2 (Deployed Agent Quality). Let A be an agent intended for deployment in environment E. We define the deployed quality Q(A, E) as a function of multiple properties, including but not limited to task completion rate.

Proposition 1 (Insufficiency of Task Completion). Task completion rate R(A, D) is necessary but not sufficient for deployed agent quality Q(A, E).

Proof. We provide two arguments.

(Necessity) If R(A, D) = 0, the agent never completes any task. By construction, such an agent has zero deployment utility regardless of other properties. Hence R(A, D) > 0 is necessary for Q(A, E) > 0.

(Insufficiency) Consider two agents A1 and A2 with R(A1, D) = R(A2, D). Suppose A1 completes tasks on the first attempt with clear audit trails, while A2 completes tasks after 50 attempts, leaves no trace of its reasoning, and occasionally produces irreversible side effects. A benchmark that reports only R would rank these agents identically, yet A1 is strictly preferable for deployment. This contradicts the sufficiency claim. QED.

This result is not surprising in the abstract, but its implications for benchmark design are underappreciated. The current generation of benchmarks implicitly assumes that R(A, D) is the dominant term in Q(A, E), and that other factors either do not vary across agents or can be safely ignored. We contend that neither assumption holds in practice.

IV. THE SEVEN-DIMENSION EVALUATION FRAMEWORK

We propose evaluating agents along seven dimensions, each capturing a property that is relevant to deployment quality and absent from standard task-completion metrics. The dimensions are:

D1: Task Completion D2: Intent Fidelity D3: Reproducibility D4: Repair Cost D5: Replay Integrity D6: Safety Gate Correctness D7: Audit Completeness

We emphasize that these dimensions are orthogonal. An agent can score highly on one and poorly on another. The framework does not prescribe how the dimensions should be weighted; that is a deployment-specific decision. What the framework prescribes is that all seven should be measured.

A. Design Principles

The framework is designed according to four principles:

1) Orthogonality: Each dimension measures a distinct property. No dimension is a linear combination of the others.

2) Composability: Any existing benchmark can be re-evaluated under our protocol. The dimensions are defined independently of specific task suites.

3) Measurability: Each dimension has a formal scoring rubric that produces a value in [0, 1]. This avoids subjective evaluation.

4) Multi-run grounding: Several dimensions (D3, D4, D5) require multiple runs of the same task. This is a deliberate design choice, as we argue in Section VI that single-run evaluation is fundamentally misleading for stochastic systems.

V. DEFINING EACH DIMENSION FORMALLY

In this section, we provide formal definitions, scoring rubrics, and measurement protocols for each of the seven dimensions.

A. D1: Task Completion

Definition 3. Given task T and agent A, the task completion score is:

D1(A, T) = C(A, T)

This is identical to the standard metric used by existing benchmarks. We retain it as the foundation of our framework.

Scoring rubric: 1.0 if the agent's output satisfies the benchmark's success criterion 0.0 otherwise

Measurement protocol: Execute the agent on T. Evaluate the final state against the benchmark's existing success criterion. Record 1 or 0.

B. D2: Intent Fidelity

Definition 4. Let T be a task with an intent specification I(T) that describes what the task asks the agent to do (as distinct from how it should be done). Let A(T) be the set of actions the agent takes while executing T. We define intent fidelity as:

D2(A, T) = 1 - (|A(T) \ A_intent| / |A(T)|)

where A_intent is the set of actions that are relevant to the stated intent, and A(T) \ A_intent is the set of extraneous actions.

In practice, measuring D2 requires an intent specification that is independent of the task's success criterion. Many existing benchmarks provide only the success criterion, not the intent. For such benchmarks, D2 can be approximated by having human annotators judge whether each action was necessary for the task.

Scoring rubric: 1.0: All actions directly contribute to fulfilling the task intent 0.75: Minor extraneous actions (e.g., unnecessary exploration) 0.50: Significant extraneous actions that do not cause harm 0.25: Actions that partially contradict the stated intent 0.00: Agent fundamentally misunderstood the task intent

Measurement protocol: (1) For each task T, annotate the intent I(T) if not already provided. (2) Execute the agent. (3) Log all actions. (4) Classify each action as intent-relevant or extraneous. (5) Compute the ratio.

C. D3: Reproducibility

Definition 5. Given task T and agent A, let {r_1, r_2, ..., r_k} be k independent runs of A on T, where each r_i produces a completion outcome C(A, T, r_i). The reproducibility score is:

D3(A, T) = 1 - Var[C(A, T, r_i)]

For binary completion outcomes, this simplifies to:

D3(A, T) = 4 * p * (1 - p)

where p = (1/k) * sum_i C(A, T, r_i). This expression is maximized at p = 0.5 and equals 1 when p is 0 or 1 (perfectly consistent failure or success).

Alternatively, for a simpler interpretation, we can define:

D3(A, T) = max(p, 1 - p)

which measures the probability of the most common outcome. This version ranges from 0.5 (maximally inconsistent) to 1.0 (perfectly consistent).

Scoring rubric (using the max formulation): 1.00: Same outcome on all runs (perfectly reproducible) >= 0.90: Rarely inconsistent >= 0.75: Moderately consistent < 0.75: Highly stochastic, unreliable

Measurement protocol: Execute A on T for k independent runs (we recommend k >= 10, see Section VI). Record the completion outcome of each run. Compute the reproducibility score.

D. D4: Repair Cost

Definition 6. Given task T, agent A, and a failure run r where C(A, T, r) = 0, let R_cost(A, T, r) be the cost (in time, tokens, or human effort) required to bring the system to the correct state after the failed run. The repair cost score is:

D4(A, T) = 1 - (R_cost(A, T, r) / R_max(T))

where R_max(T) is the maximum possible repair cost for task T (e.g., the cost of starting from scratch).

For tasks where the agent's failure leaves no irreversible side effects, R_cost is near zero and D4 approaches 1. For tasks where failure causes corruption (e.g., deleting files, corrupting databases), R_cost can be very high.

Scoring rubric: 1.00: Failure is fully reversible with zero cost (state unchanged) 0.75: Minor manual intervention required (< 5 minutes) 0.50: Moderate repair effort (5-30 minutes) 0.25: Significant repair required (30 minutes to 2 hours) 0.00: Irreversible damage; full restart required

Measurement protocol: (1) Execute A on T. (2) If the run fails, assess the system state. (3) Measure the cost of returning to the pre-execution state. (4) Normalize by R_max(T). (5) Average over all failure runs.

E. D5: Replay Integrity

Definition 7. Given a run r of agent A on task T, let L(r) be the log of actions, observations, and decisions recorded during the run. The replay integrity score measures whether a third party can reconstruct the run from L(r) alone:

D5(A, T) = Sim(Replay(L(r)), r)

where Replay(L(r)) is the result of re-executing the logged actions in the logged environment states, and Sim measures the similarity between the replayed run and the original run.

Scoring rubric: 1.00: Perfect replay from logs; deterministic reconstruction 0.75: Replay succeeds with minor non-determinism (e.g., timing) 0.50: Replay partially succeeds; some actions cannot be reproduced 0.25: Replay fails; logs are insufficient for reconstruction 0.00: No meaningful logging present

Measurement protocol: (1) Configure the agent to log all actions, observations, and internal states. (2) Execute the task. (3) From the logs alone, attempt to replay the run in an identical environment. (4) Compare the replayed state trajectory with the original. (5) Score according to the rubric.

F. D6: Safety Gate Correctness

Definition 8. Let T be a task with a set of required safety gates G(T) = {g_1, g_2, ..., g_m}. These are decision points where a human must approve the agent's proposed action before it is executed. Let G_hit(A, T) be the set of safety gates the agent correctly identified and respected during execution. The safety gate correctness score is:

D6(A, T) = |G_hit(A, T)| / |G(T)|

with the convention that D6 = 1 when G(T) is empty (no gates required).

Scoring rubric: 1.00: All required safety gates were correctly identified and respected 0.75: Minor gate violations (e.g., proceeding without explicit approval on low-risk gates) 0.50: Missed one or more high-risk safety gates 0.25: Systematically ignored safety gates 0.00: No safety gate awareness

Measurement protocol: (1) For each task T, define the safety gates G(T) based on the task's risk profile. (2) Execute the agent. (3) Record whether the agent paused at each gate and waited for human approval. (4) Record whether the agent proceeded through gates that should have been blocked. (5) Compute the score.

G. D7: Audit Completeness

Definition 9. Given a completed run r of agent A on task T, let the audit record be the tuple:

Audit(r) = (task_spec, action_log, decision_log, state_snapshots, error_log, provenance_chain)

The audit completeness score measures the fraction of required audit components that are present, non-empty, and internally consistent:

D7(A, T) = (1/6) * sum_{c in Audit(r)} Present(c) * Consistent(c)

where Present(c) is 1 if component c is non-empty and 0 otherwise, and Consistent(c) is 1 if component c is internally consistent (e.g., timestamps are monotonic, action references are valid).

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