MA-Bench: Measuring Operational Planning in Language Models

# Measuring Operational Planningin Language Models
Source: [https://arxiv.org/html/2610.19138](https://arxiv.org/html/2610.19138)
## MA\-Bench: Measuring Operational Planning in Language Models

Robert SinceroAffiliation:Scale AIPhil SageAffiliation:Data MachinesYuan \(Emily\) XueAffiliation:Scale AI

###### Abstract

How well can a language model turn a large, incomplete and partly contradictory body of documents into a plan when no single correct answer exists? We introduce Mission Analysis \(MA\)\-Bench, built on mission analysis, the first step of military operational planning, in which a staff reads the full situation and states the problem before anyone proposes a solution\. Its 10 expert\-built scenarios pair synthetic packets of ten to twelve documents with 1,257 expert\-written pass/fail requirements, each containing information on their source, question type, and importance level\. A reasoning\-model judge grades each brief against the requirements without seeing the documents; it grades like a fifth credentialed planner, leaving a four\-planner panel’s agreement unchanged \(Fleissκ\\kappa0\.42 to 0\.41\), and a judge from a second provider reproduces the model ranking \(Spearman 0\.94\)\. Across twenty frontier and open\-weights models the best gets 62% of the rubric items right\. Models are strongest on facts stated in the documents \(58%\) and weakest on judgments that must be inferred \(33%\), and six failures in ten are omissions rather than errors\. MA\-Bench grades the determinations, not the prose\. We release the packets, rubrics, prompts, scorer and every graded brief with item\-level verdicts\.

## 1Introduction

Large language models are increasingly used not only to retrieve information or answer questions, but to support complex planning and decision\-making\. However, evaluating such systems remains difficult\. Most agent benchmarks measure whether a task with an externally verifiable outcome was completed: a software issue resolved, a website navigated, a set of explicit constraints met\. Operational planning has no such outcome, and although expert rubrics now grade open\-ended work in medicine and other professions\[[3](https://arxiv.org/html/2610.19138#bib.bib3),[1](https://arxiv.org/html/2610.19138#bib.bib1)\], none covers operational planning\. A plan can be fluent, plausible, and internally coherent while omitting a critical determination, overlooking conflicting evidence, hardening an uncertain assessment into fact, or violating a governing constraint\. Nothing in such a brief is wrong in a way a reference answer would catch\. What is wrong is what is missing\. Measuring that requires knowing, for a given situation, the full set of determinations a competent staff would make and checking each one\. We study this problem through mission analysis, the step of the Joint Planning Process in which a staff transforms higher direction and a large body of operational information into a defined problem before developing courses of action\. The capability targeted is neither retrieval nor fluency, but judgment under evidence: which determinations the situation demands, and whether the system makes them\.

Figure 1:Weighted score by model, production judge\.Benchmark condition \(3,000\-word cap, medium effort\), all twenty systems; whiskers are 95% bootstrap intervals over the ten scenarios, and a perfect brief scores 1\.Figure 2:MA\-Bench construction and evaluation pipeline\.Top: benchmark construction, from operational planning task design through scenario construction, planning packets, expert ground truth, atomic rubrics, and judge calibration\. Bottom: benchmark execution, where a planning packet is provided to the system under evaluation, the resulting mission analysis brief is graded using the calibrated judge and expert rubric, and performance is decomposed by overall score, reasoning level, planning step, and critical or detrimental errors\.We introduce MA\-Bench, a benchmark for measuring this capability\. Each of its ten scenarios provides a synthetic planning packet written and validated by planning experts and asks for a mission analysis brief\. Instead of comparing the brief with a reference text, MA\-Bench grades it against an expert\-authored set of atomic requirements grounded in doctrine and scenario evidence, 1,257 in all\. Items distinguish information that can be extracted directly, conclusions that require synthesis across evidence, and planning judgments that require inference; they also distinguish omissions from detrimental actions, so the benchmark captures failures that accuracy\-style metrics obscure\. The protocol grades the brief and is agnostic to how it was produced, so the system under test can be a language model given the packet in a single prompt or a multi\-step planning system\. This paper evaluates twenty models under one fixed protocol \(Figure[1](https://arxiv.org/html/2610.19138#S1.F1)\)\.

Our main contributions are the evaluation methodology and the dataset, and the evaluation of twenty models shows what they measure:

- •A formulation of operational planning evaluation for open\-ended, high\-stakes planning tasks with heterogeneous evidence and no unique reference answer\.
- •MA\-Bench, consisting of ten expert\-validated scenarios, long multi\-document planning packets, and 1,257 expert\-authored atomic evaluation items, with a structured evaluation methodology separating extraction, synthesis, and inference while explicitly scoring both omissions and detrimental actions\.
- •An empirical evaluation of twenty frontier and open\-weights models with a judge whose rubric grading is checked against credentialed planners, analyzing overall performance, capability decomposition, failure modes, and evaluation reliability\.

## 2Mission Analysis as an Evaluation Problem

Operational planning turns direction from a higher headquarters into a plan that forces can execute\. In the United States joint doctrine, it follows the Joint Planning Process\[[46](https://arxiv.org/html/2610.19138#bib.bib46)\], and mission analysis is the first step in which the staff produces its own judgments\. Given the higher headquarters’ order, the intelligence picture, the forces available, and the commander’s initial guidance, the staff must state the problem before anyone proposes a solution: the tasks that are specified, implied and essential, the constraints and restraints it must operate within, the facts it can rely on and the assumptions it must make to keep planning, the information the commander still needs before deciding, the risks to the mission and to the force, and a restated mission in a single sentence\. These products are the foundation of every later step, so a determination missed or a fact hardened here propagates through the plan\.

For researchers, this is a long\-context reasoning task with expert ground truth and no reference answer over a large, heterogeneous, incomplete, and partly conflicting packet; for practitioners, it is a measured instrument for a task language models are already being asked to perform\.

Formally, letX=\{d1,…,dn\}X=\\\{d\_\{1\},\\ldots,d\_\{n\}\\\}denote a planning packet ofnnsource documents andAAthe planning system under evaluation, which produces an analytical artifacty=A⁡\(X\)y=A\(X\)\. Operational planning does not admit unique reference output: two briefs may differ in wording, organization, and emphasis while both are operationally sound, so the objective of the evaluation is not similar to a reference, but whetheryymakes the determinations that sound planning requires, represented as a setR=\{r1,…,rm\}R=\\\{r\_\{1\},\\ldots,r\_\{m\}\\\}of atomic requirements, each specifying the determination, the evidence or doctrinal basis that supports it, the reasoning needed to reach it, and the consequence of omitting it or introducing an incorrect or detrimental conclusion\. The benchmark asks whetheryysatisfies eachrir\_\{i\}, independently of prose, formatting, and organization\. Failures are not limited to missing information: an artifact can introduce unsupported conclusions, overstate uncertain evidence, or violate a governing constraint, so we distinguish positive requirements, determinations a sound artifact should contain, from negative requirements, specific detrimental moves it should not make, and score both\. Two artifacts of similar completeness can differ sharply in quality if one merely omits a useful determination while the other confidently states a materially wrong one\.

## 3Related Work

MA\-Bench sits at the intersection of five literatures, reviewed in Appendix[A](https://arxiv.org/html/2610.19138#A1): agent and occupation\-scale benchmarks with verifiable or expert\-graded outcomes\[[22](https://arxiv.org/html/2610.19138#bib.bib22),[33](https://arxiv.org/html/2610.19138#bib.bib33),[62](https://arxiv.org/html/2610.19138#bib.bib62),[55](https://arxiv.org/html/2610.19138#bib.bib55),[58](https://arxiv.org/html/2610.19138#bib.bib58),[38](https://arxiv.org/html/2610.19138#bib.bib38),[32](https://arxiv.org/html/2610.19138#bib.bib32)\], planning evaluations with a checkable end state\[[48](https://arxiv.org/html/2610.19138#bib.bib48),[54](https://arxiv.org/html/2610.19138#bib.bib54),[60](https://arxiv.org/html/2610.19138#bib.bib60)\], model\-based grading and its position, length and self\-preference biases\[[61](https://arxiv.org/html/2610.19138#bib.bib61),[31](https://arxiv.org/html/2610.19138#bib.bib31),[51](https://arxiv.org/html/2610.19138#bib.bib51),[11](https://arxiv.org/html/2610.19138#bib.bib11),[37](https://arxiv.org/html/2610.19138#bib.bib37)\], expert\-authored atomic rubrics\[[3](https://arxiv.org/html/2610.19138#bib.bib3),[1](https://arxiv.org/html/2610.19138#bib.bib1),[52](https://arxiv.org/html/2610.19138#bib.bib52),[17](https://arxiv.org/html/2610.19138#bib.bib17)\], and language models in military decision\-making\[[40](https://arxiv.org/html/2610.19138#bib.bib40),[27](https://arxiv.org/html/2610.19138#bib.bib27),[15](https://arxiv.org/html/2610.19138#bib.bib15)\]\. None grades a doctrinal staff product whose value lies in its defensibility, and JP 5\-0\[[46](https://arxiv.org/html/2610.19138#bib.bib46)\]supplies the standard MA\-Bench grades against\.

## 4Benchmark Design

Figure[2](https://arxiv.org/html/2610.19138#S1.F2)gives an overview\. Each MA\-Bench scenario has three fixed components: an input packet modeled on the one a planning staff would receive, an expert\-authored rubric, and a grading protocol under a calibrated model judge\.

### 4\.1Scenario packets

Each scenario is a synthetic, expert\-validated operational crisis with real geography and real actors, written in the format of an actual staff packet \(strategic context, intelligence summary and preparation brief, orders of battle, country study and geography, the initiating order, legal annexes, the commander’s initial planning guidance and running staff estimates\), 36k to 243k characters across ten to twelve documents\. No packet or rubric text exists on the public internet, so exact\-text contamination is ruled out by construction; models have seen the doctrine, staff templates, and real\-world context the scenarios draw on, and the benchmark intends that, since doctrine is the standard a brief is held to, knowing it does not supply what a particular packet says or implies \(Section[6](https://arxiv.org/html/2610.19138#S6)\)\.

The material is staff prose that describes a situation while leaving key judgments implicit\. The passage below moves from the collapse of the United Nations route through the no\-fly zone declaration to regime\-change planning that must stay separate from the protective operation, and a brief earns credit by carrying those judgments forward, not by restating the events:

GULF GUARDIAN, STRATEGIC CONTEXT, PARAS\. 4 AND 7The President sought a United Nations Security Council resolution authorizing a force to protect Cuban civilians\. The Russian Federation and the People’s Republic of China vetoed it, and both now describe the atrocity reporting as imperialist propaganda intended to manufacture a pretext for invasion\. Acting without a Security Council mandate, the President declared a no\-fly zone over the Cuban coast and stated that any further killings would be dealt with forcefully\. The United States thus acts on a civilian\-protection rationale under customary international law, over the objection of two great powers, and the legitimacy of that case is now itself a strategic center of gravity\.\[ … \]The direction to prepare, on order, plans for operations ashore and for regime change hangs over the whole effort\. It is planning only, gated on a decision by the National Command Authority, and it must be held apart, in fact and in perception, from the protective operation that begins now, lest it hand Havana, Moscow, and Beijing the invasion narrative they are seeking\.

The corpus is balanced across five design axes \(plan type, domain, stakeholder mix, time pressure, and operational\-environment complexity; target distribution in Appendix[B](https://arxiv.org/html/2610.19138#A2)\)\. A source index records each document’s visibility and the rationale when it is withheld: withheld documents are downstream products of a completed mission analysis \(component orders, the commander’s critical information requirements, event templates\) that ground the rubric during authoring and never reach the system under test\. Exclusion is enforced by construction and checked before every run: the released document set holds only the visible documents, each with a content hash in the bundle manifest, the packet and any multi\-step system’s retrieval index are assembled from that set alone, and the grading runner verifies every manifest hash before its first call and writes the artifact hashes to its run log, which ships with the release, so each reported number is tied to a specific packet build\. The packets are deliberately incomplete: some reporting is unconfirmed and marked as such, and some figures from different originators do not reconcile\. Recognizing these limits is itself scored\.

### 4\.2Rubrics

Each scenario has one expert\-authored rubric of 74 to 170 items, 1,257 in all, authored against the packet, reviewed by credentialed planners, versioned and frozen before evaluation, so the same version grades every system in a comparison\. Each item meets six requirements: atomic \(one claim or behavior\), binary, observable in the submitted brief rather than in intent or process, grounded in doctrine or packet evidence with a resolvable citation, self\-contained \(gradable without opening the packet\), and non\-duplicative\. A directive to “protect infrastructure and deter sabotage” becomes two items, and vague completeness tests, prose quality, and anything satisfiable by copying obvious text are prohibited\.

Thetierrecords how the answer is grounded\. Tier 1 items are stated outright in a single document \(Appendix[C](https://arxiv.org/html/2610.19138#A3)shows one\)\. Tier 2 items require synthesis across several facts\. Tier 3 items are planning judgments that appear in no document and must be inferred; they are the most valuable and the hardest\. A Tier 3 item:

C5:GG\-S1\-05v1Tier 3, I, Step S1QUESTIONDoes the response surface the tension between protecting civilians now and the still\-gated regime\-change tasker?PASSFrames the tension and the need to keep the two apart in fact and in perception\.FAILIgnores the tension or merges regime change into the base operation\.SOURCECommander’s Initial Planning Guidance §2\.

Theseverityis a signed importance label fixed at authoring time; the sign says whether the item is desirable and the magnitude how much it moves the score, under a weight mapping declared and frozen before each run \(Section[4\.3](https://arxiv.org/html/2610.19138#S4.SS3)\):

Negative items name a specific wrong move, such as treating a moderate\-confidence attribution as confirmed fact, and the brief is penalized when the move appears \(Appendix[C](https://arxiv.org/html/2610.19138#A3)\)\.

Each item is also assigned to one of the twelve mission analysis steps \(higher mission and intent, operational environment, task analysis, limitations, information requirements, assumptions, risk, restated mission, decision points, facts, forces and objectives\), so scores decompose by step\. Ordering, formatting, and style earn nothing\.

### 4\.3Grading and scoring

A single reasoning model grades each brief against the full rubric in one call, returning only the items the brief fails, each with quoted evidence and a rationale tied to the fail condition, in a schema\-enforced format; unlisted items pass\. For a negative item, the pass condition is the presence of the flagged wrong move, so a listed negative item is a mistake the brief avoided and an unlisted one a mistake it committed\. Malformed responses are rejected and retried, and no accepted verdict lists fewer than 13 items\. An item the brief does not clearly satisfy fails, with no partial credit, and the judge never sees the packet, so grading measures the brief against the rubric rather than the judge’s reading of the scenario\. The judge is selected by measurement: candidates are compared on the expert\-graded sample of Section[5\.6](https://arxiv.org/html/2610.19138#S5.SS6)and admitted only if their chance\-corrected agreement with the expert majority is at least the experts’ mean agreement with one another and theirF1F\_\{1\}on the fail class reaches0\.800\.80\. The production judge clears both gates,κ=0\.54\\kappa=0\.54against an expert mean of0\.430\.43andF1=0\.82F\_\{1\}=0\.82on 190 item verdicts graded by four planners; the judge was frozen before any benchmark brief was graded, and every result is reproduced under a second judge from another provider \(Section[5\.5](https://arxiv.org/html/2610.19138#S5.SS5)\)\. Between the expert study and the final freeze one item was restored, five were reworded and thirteen negative items were corrected for polarity \(Section[5\.6](https://arxiv.org/html/2610.19138#S5.SS6)\)\.

The base score is the unweighted fraction of rubric items passed\. The severity\-weighted score uses the declared mapping: withPPthe positive items \(CI, I, SI\),NNthe negative items \(D, CD\), andwiw\_\{i\}the weight of itemii,

S=∑i∈Pwi​\[isatisfied\]−∑j∈N\|wj\|​\[jpresent\]∑i∈Pwi,S\\;=\\;\\frac\{\\sum\_\{i\\in P\}w\_\{i\}\\,\[\\text\{$i$ satisfied\}\]\\;\-\\;\\sum\_\{j\\in N\}\|w\_\{j\}\|\\,\[\\text\{$j$ present\}\]\}\{\\sum\_\{i\\in P\}w\_\{i\}\},so a perfect brief scores11, a brief that meets no requirement and makes no listed wrong move scores00, and wrong moves are charged in the same units as omissions\. Scores therefore place systems on one scale for comparison and are not calibrated against human\-written briefs, which the benchmark does not include \(Section[6](https://arxiv.org/html/2610.19138#S6)\)\. The score is not clamped, since flooring at zero would hide the behavior negative items are meant to catch \(worked example in Appendix[D](https://arxiv.org/html/2610.19138#A4)\); seeds are averaged within a scenario before any comparison, and the benchmark is agnostic about how a brief was produced\.

## 5Experiments

### 5\.1Setup

Sixteen models are evaluated in the benchmark condition: Claude Opus 5, Claude Fable 5\.1, GPT\-6 Astra, GPT\-5\.6 Sol and luna, Gemini 3\.1 Pro, Grok 4\.6, Mistral Medium 3\.5, Muse Spark 1\.3 and Qwen3\.8\-Max through their API providers, and the open\-weights GLM\-5\.3, DeepSeek\-V4\-Pro, Kimi K3, MiniMax M3, Nemotron 3 Ultra and Gemma 4 31B; Claude Sonnet 5, GPT\-5\.4, Gemini 3\.8 Flash and DeepSeek\-V4\-Flash form a capability ladder\. Every model receives the same task prompt naming the twelve mission analysis steps, followed by the full packet \(Appendix[L](https://arxiv.org/html/2610.19138#A12)\), a 3,000\-word cap enforced before grading, medium reasoning effort where we set it and the provider default otherwise \(Appendix[F](https://arxiv.org/html/2610.19138#A6)lists each run’s setting\), and at least three independent briefs per scenario, five for the three models run first; outputs that end in a provider content filter are graded as delivered and counted as refusals; the benchmark comprises 1,020 graded briefs across these conditions, and 540 uncapped briefs extend the length ablation to every model \(Appendix[J](https://arxiv.org/html/2610.19138#A10)\)\. The cap is part of the protocol\. Models are told the limit in the prompt, it is about the length of a staff mission analysis brief, and it keeps scores from tracking length, which they follow far more closely without it \(Spearman 0\.70 against 0\.26\), while the ranking largely holds \(Spearman 0\.95, Appendix[J](https://arxiv.org/html/2610.19138#A10)\)\. The production judge is gpt\-5\.6 at high reasoning effort with the frozen prompt of Section[4\.3](https://arxiv.org/html/2610.19138#S4.SS3), one call per brief and no access to the packet; Gemini 3\.1 Pro regrades every brief, and a common subset of 216 benchmark\-condition briefs \(six scenarios, ten models, every seed\) is regraded by both Gemini 3\.1 Pro and Claude Opus 5 \(Section[5\.5](https://arxiv.org/html/2610.19138#S5.SS5)\)\. The scenario is the unit of analysis: seeds are averaged within a scenario, means and 95% bootstrap percentile intervals are taken over the ten scenarios\[[12](https://arxiv.org/html/2610.19138#bib.bib12)\], comparisons between conditions of one model are paired by scenario, and we report the unclamped weighted score of Section[4\.3](https://arxiv.org/html/2610.19138#S4.SS3), items correct \(a negative item counts as correct when its mistake is absent\), and the positive pass rate\.

### 5\.2Main results

Figure[1](https://arxiv.org/html/2610.19138#S1.F1)reports the benchmark condition, with the numbers in Table[4](https://arxiv.org/html/2610.19138#A5.T4)\(Appendix[E](https://arxiv.org/html/2610.19138#A5)\)\. The best model, Muse Spark 1\.3, gets 62% of rubric items right for a weighted score of 0\.574, with Grok 4\.6 at 0\.540, Claude Opus 5 at 0\.514, and GLM\-5\.3, the best open\-weights model, at 0\.505\. The sixteen models span 0\.30 to 0\.57, so the benchmark separates systems that are close on other leaderboards\. No model approaches the ceiling, and with intervals about±0\.08\\pm 0\.08wide, adjacent models are not separated; only the ends of the table are\. Between two fifths and two thirds of the determinations a planning staff would require are missing from every brief, and every brief commits three to five flagged wrong moves, about two of them critical\.

Three features of the table recur throughout the paper\. GPT\-6 Astra commits the fewest wrong moves \(3\.1 per brief, 1\.4 critical\) while ranking fifth on coverage, so coverage and commission are separable qualities that one accuracy figure would conflate\. The two GPT\-5\.6 variants land within 0\.01 of one another, the resolution expected from two serving configurations of one model\. Claude Fable 5\.1’s wide interval is a refusal effect: its content filter terminated every brief on Jagged Anvil and four of five on Pacific Harrier, mid\-sentence and without a refusal message, and those outputs are graded as delivered, because a planning system that declines two crises in ten is a fact about the system\. Without those nine briefs, it scores 0\.510 \(0\.432, 0\.595\) over the nine scenarios that keep a brief, level with Claude Opus 5\.

Figure 3:Pass rate by grounding tier and model, benchmark condition, production judge\. Dashed lines are the pooled rates \(58\.1, 49\.0 and 33\.4\)\.
### 5\.3Where models fail

Pooled over the benchmark condition, positive items pass at 58\.1% when the answer is stated in a single document \(Tier 1\), 49\.0% when it must be assembled from several \(Tier 2\) and 33\.4% when it must be inferred \(Tier 3\), and the gradient holds for every model \(Figure[3](https://arxiv.org/html/2610.19138#S5.F3)\)\. Tier 3 items make up 36% of the rubric, so the planning judgments the benchmark was built to measure also account for the largest share of the missing credit\. Critically important items pass at 56\.9% and important items at 37\.5%: models make the headline determinations and miss the second\-order ones a reviewing staff would consider material\. By step \(Figure[5](https://arxiv.org/html/2610.19138#A7.F5), Appendix[G](https://arxiv.org/html/2610.19138#A7)\), models are strongest where the packet states the answer and the step carries it forward \(constraints and restraints 72%, higher mission and intent 66%\) and weakest on the steps that look forward from the situation to the decisions it will force \(commander’s critical information requirements 31%, decision points and named areas of interest 38%, force and resource analysis 41%\)\. The ordering holds on the 285 briefs that never reached the cap \(28% and 36% on the first two\), so it is not an artifact of truncation\. Models describe the situation they are given far better than they anticipate the decisions it will demand\.

The judge’s rationale for every failed item says what kind of failure it was\. A keyword classification of the 31,882 failed positive items assigns 60\.2% to outright omission, 8\.2% to an incomplete treatment, 2\.5% to content filed under the wrong step, and 1\.6% to incorrect or unsupported content, with 28% unassigned, and the proportions barely move across models, tiers, or severities \(Appendix[H](https://arxiv.org/html/2610.19138#A8)\)\. Models rarely say something the rubric can catch as wrong; they leave things out, which is why a reference\-similarity or accuracy metric would miss most of what the rubric catches: there is no wrong sentence to detect\. Wrong moves are the exception the negative items exist to catch\. A flagged mistake is committed on 25\.9% of detrimental and 28\.3% of critically detrimental opportunities, about four per brief, more often on plainly stated traps \(35% of Tier 1 opportunities against 21% of Tier 3\) such as treating an unconfirmed report as fact, and concentrated on the known\-facts step, where the flagged mistake is committed on 44% of opportunities\. Only the positive items pay\.

One item from the first of Claude Opus 5’s briefs on Gulf Guardian shows what these failures look like in practice: the item, what the brief did, and the judge’s rationale verbatim\.

C5:C\-06v1Tier 3, CI, Step S2ITEMDoes the analysis describe how the commander’s operational approach of protecting civilians will weaken the Cuban center of gravity?BRIEFLists the regime’s critical vulnerabilities in one section and calls for the release of evidence of the killings in another\.JUDGE“The response lists regime vulnerabilities and separately calls for evidence release, but never explains how civilian protection directly weakens coercive control and the regime’s blame\-shifting narrative\.”

This is the characteristic Tier 3 failure\. Every fact the inference needs is on the page, and the inference is not\. The characteristic Tier 1 failure, from the same brief, is traced in full in Appendix[C](https://arxiv.org/html/2610.19138#A3): the packet names seven partner governments in one table and the brief, which cites that table three times, writes “willing regional partners”\. Nothing in either would trouble a reader judging fluency\. Both would trouble the staff that had to plan from the brief\. The appendix adds a third card, from the information\-requirements step that scores lowest of the twelve\.

### 5\.4Length, reasoning effort and model scale

Scores are not a proxy for length\. Within the capped condition, the rank correlation between a model’s raw brief length and its score is 0\.26 \(Pearson 0\.15\) across the twenty systems, and the longest writer, Gemini 3\.8 Flash, ranks fourteenth\. Removing the cap raises a model’s score \(GPT\-6 Astra by 0\.078, GPT\-5\.4 by 0\.123\), so models hold more rubric\-relevant content than a staff\-length brief can carry \(Appendix[J](https://arxiv.org/html/2610.19138#A10)\)\.

Neither more compute nor a bigger model closes the gap on its own\. Moving reasoning effort from low to high shifts a model’s score by at most 0\.08 across five models, with no consistent sign, even as reasoning tokens rise by one to two orders of magnitude \(Appendix[J](https://arxiv.org/html/2610.19138#A10)\)\. Within a family, the stronger member wins in three of four cases: Claude Opus 5 over Sonnet 5 by 0\.12, GPT\-6 Astra over GPT\-5\.4 by 0\.115, and DeepSeek\-V4\-Pro over V4\-Flash by 0\.05, with the Gemini pair tied\.

### 5\.5Sensitivity to the judge

Table 1:Agreement among three judgeson a common set of 216 benchmark\-condition briefs \(six scenarios, ten models, every seed, 27,540 item verdicts per pair\): item agreement, Cohen kappa, Spearman correlation of the ten model means, and each judge’s self\-preference excess on its own family \(first / second judge\)\.The choice of judge could, in principle, determine every number above, so tjudges from two other providers regrade the briefs with the same frozen prompt\. Gemini 3\.1 Pro regrades all 1,050 briefs and agrees with the production judge on 84\.0% of 131,985 item verdicts, Cohen’sκ=0\.678\\kappa=0\.678\[[9](https://arxiv.org/html/2610.19138#bib.bib9)\], with a Spearman correlation of 0\.94 between the two judges’ means over the sixteen benchmark\-condition models\. On a common set of 216 briefs \(six scenarios, ten models, every seed\) all three judges are compared pairwise \(Table[1](https://arxiv.org/html/2610.19138#S5.T1)\): agreement runs from 80\.0% to 85\.1% \(κ\\kappa0\.61 to 0\.70\), in every case above the agreement between two human experts on this task \(Section[5\.6](https://arxiv.org/html/2610.19138#S5.SS6)\), and the rankings are stable \(Spearman 0\.89 to 0\.94\)\. The alternate judges are more lenient by a roughly constant offset, which moves every model together and leaves the order intact \(Appendix[K](https://arxiv.org/html/2610.19138#A11)\)\. Self\-preference, a documented failure mode of model judges\[[37](https://arxiv.org/html/2610.19138#bib.bib37),[61](https://arxiv.org/html/2610.19138#bib.bib61)\], is measured rather than assumed: for each pair of judges we take the gap between their scores on one judge’s own model family and subtract the same gap on all other families\. Across the three pairs the excess ranges from−0\.029\-0\.029to\+0\.005\+0\.005, so no judge favors its own family by more than 0\.03, less than the width of any single model’s interval\.

### 5\.6Agreement with experts

Table 2:Judge against a four\-expert panel, by severity, on the 164 of 190 expert\-graded verdicts with a majority \(26 split two against two\)\. Fail columns are the shares each side failed\. Candidate judges are compared in Table[11](https://arxiv.org/html/2610.19138#A11.T11)\.Four JPME\-credentialed planners independently graded the same 190 item verdicts, ten briefs by nineteen items covering every tier and severity, with the information the judge receives and not the packet \(Table[2](https://arxiv.org/html/2610.19138#S5.T2)\)\. On 26 items the experts split two against two, so judge agreement is measured on the 164 with a majority\. The experts agree with one another at Fleissκ=0\.42\\kappa=0\.42\[[14](https://arxiv.org/html/2610.19138#bib.bib14)\], pairwise 0\.30 to 0\.60 with mean 0\.43, which bounds how well any judge can be validated against them; the production judge agrees with the majority on 78\.0% \(κ=0\.54\\kappa=0\.54,F1F\_\{1\}on the fail class 0\.82\), and treated as a fifth rater its mean pairwiseκ\\kappawith them is 0\.40, inside their range, leaving the panel’s Fleissκ\\kappaunchanged \(0\.42 to 0\.41\)\. Holding out each planner in turn, the judge agrees with the majority of the other three at meanκ=0\.46\\kappa=0\.46, against 0\.52 for the held\-out planner \(0\.42 to 0\.62\), and a three\-planner majority has no ties\. Agreement is flat across tiers,κ\\kappa0\.53, 0\.56 and 0\.51 on Tiers 1 to 3, so the judge is no less reliable on the inference items the benchmark leans on\. The prompt was chosen on this sample by agreement alone: the stricter of two scoring\-rule variants won on a pre\-declared half of the items and on all of them \(0\.61 and 0\.54 against 0\.52 and 0\.46\) and was frozen before any benchmark brief was graded; a repeat run and the 137 items untouched by the final rubric revision moveκ\\kappaby 0\.004 and to 0\.51 \(Appendix[K](https://arxiv.org/html/2610.19138#A11)\)\. The alternate judges reach 0\.43 \(Gemini 3\.1 Pro\) and 0\.34 \(Claude Opus 5\) against the same majority, so only the production judge clears the gate of Section[4\.3](https://arxiv.org/html/2610.19138#S4.SS3)\. Agreement is high on positive items and lower on negative ones for experts and judge alike \(Table[2](https://arxiv.org/html/2610.19138#S5.T2)\); the graders’ notes trace the drop to polarity, since a pass on a negative item means the mistake is present, and thirteen items worded the other way round were corrected in a documented errata before benchmark grading\.

## 6Discussion and Conclusion

MA\-Bench targets a planning capability that no verifiable\-outcome benchmark reaches: turning a large, incomplete and partly contradictory body of evidence into the determinations a staff needs before it can plan\. The best current model gets 62% of the rubric items right; the missing share sits in the inference tier and in the steps that look forward from the situation to the decisions it will force, and the failures are omissions rather than errors, invisible to any metric that checks what a brief says instead of what it should have said\. Three judges from three providers and four human experts see the same picture, which we take as evidence that the rubric is applied consistently and that the results do not depend on one grader\. Every score is a model’s verdict: the judge grades like a fifth credentialed planner, leaving the panel’s agreement unchanged, two judges from other providers reproduce the ranking at Spearman 0\.89 and above with no self\-preference beyond 0\.03, and every verdict carries the quoted evidence and rationale on which it rests\. Planners graded model briefs in the expert study but wrote none of their own, so the paper has no human baseline\. Real planning packets are too sensitive to use, and a human\-written brief takes a planning team a week or more, so we built expert\-written synthetic packets and spent that expert time on rubric items instead\. The expert study shows that the judge applies the rubric as planners do\. Showing that a higher score means a better mission analysis needs a holistic expert rating of briefs against the packets, and a small set of human\-written briefs would anchor the scale\.

The remaining limits are properties of the instrument as run, each recorded in the released verdicts\. Agreement on detrimental items is lower for the judge and the experts alike \(κ\\kappa0\.21 to 0\.37\), and negative items make up 12% of the rubric and enter the score subtractively\. Bootstrap intervals over ten scenarios are about±0\.08\\pm 0\.08wide, so adjacent models are not separated, while the ends of the table are\. No packet or rubric text exists outside the benchmark, and models’ knowledge of joint doctrine is intended: doctrine says what a mission analysis should contain, not what this packet says or implies\. The benchmark covers one step of one planning process in one doctrinal tradition; the length cap truncates many briefs, and the uncapped ablation prices the cost, and provider content filters ended nine briefs, which are counted\. Every packet, rubric, prompt, brief and verdict is released so that the next model can be measured against the same standard\.

## Data availability

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## Appendix AExtended related work

MA\-Bench sits at the intersection of five bodies of literature: agentic task benchmarks, planning evaluation, model\-based \(LLM\-as\-judge\) grading and its reliability, rubric\-based evaluation of open\-ended professional work, and the emerging study of language models in military decision\-making\. MA\-Bench addresses a gap spanning all five: no public benchmark uses expert\-authored atomic rubrics to grade a planning system’s performance on the first step of the Joint Planning Process against codified documents\.

### A\.1Agentic task benchmarks and the fluency bias

The current generation of agent benchmarks shares a recipe: draw tasks from economically valuable work, then score whether an agent completes them\. SWE\-bench\[[22](https://arxiv.org/html/2610.19138#bib.bib22)\]and SWE\-Lancer\[[35](https://arxiv.org/html/2610.19138#bib.bib35)\]score resolved GitHub issues and paid freelance tickets; GAIA\[[33](https://arxiv.org/html/2610.19138#bib.bib33)\]and BrowseComp\[[53](https://arxiv.org/html/2610.19138#bib.bib53)\]score tool\-use and browsing chains; WebArena and its visual successor\[[62](https://arxiv.org/html/2610.19138#bib.bib62),[25](https://arxiv.org/html/2610.19138#bib.bib25)\]and OSWorld\[[55](https://arxiv.org/html/2610.19138#bib.bib55)\]score web and desktop workflows; AgentBench\[[30](https://arxiv.org/html/2610.19138#bib.bib30)\]aggregates across environments;τ\\tau\-bench\[[58](https://arxiv.org/html/2610.19138#bib.bib58)\]adds a simulated user; MLE\-bench\[[6](https://arxiv.org/html/2610.19138#bib.bib6)\]and PaperBench\[[43](https://arxiv.org/html/2610.19138#bib.bib43)\]score end\-to\-end research engineering\. Occupation\-scale suites such as GDPval\[[38](https://arxiv.org/html/2610.19138#bib.bib38)\], the Remote Labor Index\[[32](https://arxiv.org/html/2610.19138#bib.bib32)\], APEX\[[49](https://arxiv.org/html/2610.19138#bib.bib49)\], and ProfBench\[[52](https://arxiv.org/html/2610.19138#bib.bib52)\]extend the recipe toward whole professions\. These benchmarks reward usable artifacts produced in a stable, cooperative environment\. UserBench\[[39](https://arxiv.org/html/2610.19138#bib.bib39)\]documents one blind spot, agents that guess rather than elicit what an underspecified goal leaves out \(full alignment with user intent on 20% of tasks\), and PRBench\[[1](https://arxiv.org/html/2610.19138#bib.bib1)\]another, conclusions reached through inaccurate judgments and opaque, incomplete reasoning on open\-ended professional tasks\. MA\-Bench targets those blind spots in planning, where the artifact is neither code nor a booking but a staff product whose value lies in its defensibility against doctrine requirements\.

### A\.2Evaluating planning

Planning has long provided a particularly sharp lens on the gap between fluent generation and grounded reasoning\. PlanBench\[[48](https://arxiv.org/html/2610.19138#bib.bib48)\]showed that planning claims drawn from common\-sense tasks do not survive classical planning domains with automated plan validation \(GPT\-4 solves 34% of Blocksworld plan\-generation instances\); follow\-up work argues that chain\-of\-thought does not close the gap\[[44](https://arxiv.org/html/2610.19138#bib.bib44)\]and that LLMs are better used as components within verifier loops than as sole planners\[[23](https://arxiv.org/html/2610.19138#bib.bib23)\]\. Applied planning benchmarks reach similar conclusions in richer settings: TravelPlanner\[[54](https://arxiv.org/html/2610.19138#bib.bib54)\]reports single\-digit success on multi\-constraint itineraries; NATURAL PLAN\[[60](https://arxiv.org/html/2610.19138#bib.bib60)\]shows that performance degrades as the number of constraints increases, most sharply in trip and meeting planning\. QuestBench\[[28](https://arxiv.org/html/2610.19138#bib.bib28)\]examines the complementary skill of asking the right clarifying question, building on research into ambiguity and clarification\[[34](https://arxiv.org/html/2610.19138#bib.bib34),[2](https://arxiv.org/html/2610.19138#bib.bib2),[59](https://arxiv.org/html/2610.19138#bib.bib59)\]\. Prompting scaffolds such as ReAct\[[57](https://arxiv.org/html/2610.19138#bib.bib57)\]and Reflexion\[[42](https://arxiv.org/html/2610.19138#bib.bib42)\], and search scaffolds such as Tree of Thoughts\[[56](https://arxiv.org/html/2610.19138#bib.bib56)\], improve exploration and self\-correction and have been tested on question answering, text\-based games, coding and puzzle\-like domains with verifiable end states\. Mission analysis differs in kind: the “plan” is a structured analytical product with no single correct answer and is graded on whether required determinations \(tasks, assumptions, CCIRs, risks\) are present, sourced, and doctrinally sound; this setting is not covered by any of the above benchmarks\. Reasoning\-optimized models\[[36](https://arxiv.org/html/2610.19138#bib.bib36),[18](https://arxiv.org/html/2610.19138#bib.bib18)\]raise scores on verifiable domains, making a rubric\-graded, non\-verifiable domain a natural next target\.

### A\.3LLM\-as\-judge: capability and known failure modes

Model\-based grading is now standard where reference answers do not exist\. MT\-Bench and Chatbot Arena established the feasibility of model\-based grading and its correlation with human preference\[[61](https://arxiv.org/html/2610.19138#bib.bib61),[7](https://arxiv.org/html/2610.19138#bib.bib7)\]; G\-Eval formalized criterion\-prompted judging\[[31](https://arxiv.org/html/2610.19138#bib.bib31)\]; Prometheus trained open evaluators using fine\-grained scoring rubrics\[[24](https://arxiv.org/html/2610.19138#bib.bib24)\]; RewardBench benchmarks the graders themselves\[[26](https://arxiv.org/html/2610.19138#bib.bib26)\]\. The failure modes are equally well documented: position bias\[[51](https://arxiv.org/html/2610.19138#bib.bib51)\], length bias and its correction\[[11](https://arxiv.org/html/2610.19138#bib.bib11)\], and self\-preference, in which evaluators favor their own generations\[[37](https://arxiv.org/html/2610.19138#bib.bib37)\]\. MA\-Bench’s judge design responds directly to this literature\. The judge is selected by measured agreement with an expert panel, must cite the rubric item’s embedded ground truth in every verdict, and returns only failed items under an enforced schema; since unlisted items pass, a malformed or truncated verdict would inflate positive items and penalize negative ones, so such responses are rejected and retried, and the shortest accepted verdict lists 13 items\. Section[5\.5](https://arxiv.org/html/2610.19138#S5.SS5)regrades the briefs under judges from two other providers and measures self\-preference directly, finding none beyond 0\.03\.

### A\.4Rubric\-graded evaluation of professional work

A parallel thread replaces preference judgments with expert\-authored, criterion\-level rubrics\. HealthBench applies physician\-authored criteria to clinical dialogues\[[3](https://arxiv.org/html/2610.19138#bib.bib3)\]; ProfBench extends rubric grading across professional domains\[[52](https://arxiv.org/html/2610.19138#bib.bib52)\]; recent work directly examines rubric generation and aggregation\[[17](https://arxiv.org/html/2610.19138#bib.bib17),[21](https://arxiv.org/html/2610.19138#bib.bib21),[10](https://arxiv.org/html/2610.19138#bib.bib10)\], and rubric\-style checklists now serve as reward signals for post\-training\[[17](https://arxiv.org/html/2610.19138#bib.bib17),[50](https://arxiv.org/html/2610.19138#bib.bib50)\]\. MA\-Bench adopts the same philosophy of atomic, binary, self\-contained criteria and adds three properties not previously combined in this literature: every criterion carries a doctrinal citation \(JP 5\-0\[[46](https://arxiv.org/html/2610.19138#bib.bib46)\]\), a grounding tier that distinguishes extraction, synthesis, and inference, and a severity taxonomy in which critical omissions and doctrinally detrimental behaviors are scored asymmetrically\. Grading targets what a brief determines, not the prose: fluency earns nothing\.

### A\.5Language models in military decision\-making

Interest in LLMs for military planning is no longer hypothetical: the Department of Defense has moved from studying generative AI to piloting it across operational and administrative applications\[[8](https://arxiv.org/html/2610.19138#bib.bib8)\], while how to evaluate them remains an open question\. Research to date has focused on behavior rather than competence: escalation dynamics in simulated crises\[[40](https://arxiv.org/html/2610.19138#bib.bib40)\], behavioral divergence between expert humans and models in wargames\[[27](https://arxiv.org/html/2610.19138#bib.bib27)\], multi\-agent historical simulation\[[20](https://arxiv.org/html/2610.19138#bib.bib20)\], and RAND’s assessment of the limits of AI, including large language models, for wargaming\[[15](https://arxiv.org/html/2610.19138#bib.bib15)\]\. COA\-GPT\[[16](https://arxiv.org/html/2610.19138#bib.bib16)\]conditions course\-of\-action generation on doctrine excerpts but evaluates the results by simulated engagement outcomes, not by doctrinal correctness\. Doctrinal publications such as JP 5\-0, which specifies mission analysis\[[46](https://arxiv.org/html/2610.19138#bib.bib46)\], JP 3\-0\[[47](https://arxiv.org/html/2610.19138#bib.bib47)\], and the CJCS manual series\[[5](https://arxiv.org/html/2610.19138#bib.bib5)\], provide the codified standard against which MA\-Bench grades\. Human\-factors work on decision\-support trust\[[45](https://arxiv.org/html/2610.19138#bib.bib45),[13](https://arxiv.org/html/2610.19138#bib.bib13),[4](https://arxiv.org/html/2610.19138#bib.bib4)\]motivates the severity\-weighted, veto\-carrying score MA\-Bench reports to commanders\.

### A\.6Benchmark validity

Finally, MA\-Bench’s design responds to critiques of static\-benchmark validity: contamination\[[41](https://arxiv.org/html/2610.19138#bib.bib41)\], the limits of static knowledge\-style suites\[[19](https://arxiv.org/html/2610.19138#bib.bib19)\], and the gap between leaderboard scores and deployed behavior\[[29](https://arxiv.org/html/2610.19138#bib.bib29)\]\. Scenarios are synthetic and expert\-validated, so no packet or rubric exists on the public internet; withheld answer documents are quarantined from the system under test by construction; and the protocol grades the brief alone, so any system that produces one can be scored against the same standard\.

## Appendix BCorpus

Table[3](https://arxiv.org/html/2610.19138#A2.T3)lists the ten scenarios with the size of each packet and rubric, and Figure[4](https://arxiv.org/html/2610.19138#A2.F4)shows the severity mix of each rubric\.

Table 3:Scenarios\.Packet size counts the documents visible to the system under test\. Target distribution across the design axes: plan type \(contingency 60%, crisis 25%, campaign 15%\), domain \(multi\-domain 75%, single\-domain 25%\), stakeholder mix \(U\.S\.\-only 25%, bilateral 30%, multinational 35%, whole\-of\-government 10%\), time pressure \(deliberate 60%, compressed 30%, crisis 10%\), and operational\-environment complexity \(permissive 25%, contested 50%, highly contested 25%\)\. Rubric totals by severity are CI 484, I 536, SI 80, D 82 and CD 75, and by tier 400, 406 and 451 for Tiers 1 to 3\.Figure 4:Severity composition of each scenario’s rubric\.Wedges from twelve o’clock clockwise: critically important, important, slightly important, detrimental, critically detrimental\. The authoring guideline kept every category above 5% of the corpus and every scenario’s smallest category above 2%, so the scoring behavior is not driven by any one scenario’s mix\.
## Appendix CAdditional rubric items and failure examples

A Tier 1 item, stated outright in the packet, and a critically detrimental item, penalized when the brief commits the move it names, complement the Tier 3 item shown in Section[4\.2](https://arxiv.org/html/2610.19138#S4.SS2)\.

C5:GG\-S1\-02v1Tier 1, CI, Step S1QUESTIONDoes the response identify that the President declared a No\-Fly Zone over the Cuban coast and warned further killings would be met forcefully?PASSStates the declared NFZ and the forceful\-response warning\.FAILOmits the NFZ declaration or treats it as merely proposed\.SOURCEStrategic Context; EXORD para\. 3\.

C2:R102Tier 2, CD, Step S6QUESTIONDoes the analysis treat the Iranian proxy attribution as confirmed fact rather than a moderate\-confidence assessment?BASISThe intelligence summary states the attribution is a cross\-source assessment, not a finding\. A brief that hardens it into fact is penalized\.

A third failure from the same Claude Opus 5 brief as the two in Section[5\.3](https://arxiv.org/html/2610.19138#S5.SS3), on the commander’s critical information requirements step, which scores lowest of the twelve\. The information requirement exists but is not tied to the decision it should inform\.

C5:GG\-S5\-06Tier 3, I, Step S5ITEMDoes the response derive a friendly force information requirement on branch readiness \(ashore and regime change\) and Nimitz carrier strike group availability, tied to the recommendation to the National Command Authority?BRIEFFFIR 2 asks whether the Nimitz strike group and the amphibious ready group will be available\.JUDGE“FFIR 2 addresses Nimitz and ARG availability but not readiness of the ashore and regime\-change branches or the NCA\-recommendation decision\.”

The Tier 1 counterpart of the card in Section[5\.3](https://arxiv.org/html/2610.19138#S5.SS3), from the same brief, traced from the packet passage the item tests to the judge’s verdict, shows what the judge sees and what it decides on\. The item belongs to the known\-facts step\. The packet states the fact in one table\. The brief, the first of Claude Opus 5’s three on Gulf Guardian, cites that paragraph three times, never reproduces it, and its known\-facts section does not mention partners at all\. Another of the model’s three briefs on this scenario names all seven governments, so the item is answerable within the word cap\.

C5:GG\-S10\-06v1, full traceTier 1, I, Step S10PACKETDocument 04, Coalition Order of Battle, paragraph 8, heading and the four rows of its table: “COALITION PARTNERS AND INTERNATIONAL ORGANIZATIONS\. Terms, consent, and capacity remain to be arranged\.” United Kingdom: Caribbean patrol presence\. Jamaica, Dominican Republic, Colombia, Mexico: patrol, coordination; wary of onward migration\. Trinidad and Tobago, The Bahamas: willing to receive Cubans until conditions on the island change\. UN High Commissioner for Refugees \(UNHCR\): supervision of reception and processing\.ITEMDoes the response state the partner offers \(United Kingdom, Jamaica, Dominican Republic, Colombia, Mexico\), the host nations \(Trinidad and Tobago, the Bahamas\) and UNHCR?PASSNames the partners, the host nations willing to receive Cubans, and UNHCR\.FAILRefers to generic “allies” without naming partners or host nations\.BRIEF*Higher headquarters’ intent:*“act with willing regional partners and sustain legitimacy of the civilian\-protection case\.”BRIEF*Tasks:*“Negotiate partner terms, consent, and capacity, and UNHCR supervision arrangements \(Docs 04 para 8; 12\)\.”BRIEF*CCIRs:*“FFIR 4\. Status of partner consent, capacity, and UNHCR terms \(Docs 04 para 8; 12\)\. Supports burden\-sharing decision\.”BRIEF*Assumptions:*“Willing regional partners and the UN will provide burden\-sharing reception once terms are agreed\.”BRIEF*Known facts:*no mention of partners, host nations or UNHCR\.JUDGEFail\. “The brief refers generically to willing regional partners and partner facilities but does not name the UK, Jamaica, Dominican Republic, Colombia, Mexico, Trinidad and Tobago, and the Bahamas\. The pass condition requires the named partners, named host nations, and UNHCR\.”SCOREThe item’s weight of 5 is forgone\. No penalty is added: only the negative items penalize, and this brief committed none of the moves this item is adjacent to\.

The brief points at the paragraph that holds the answer three times and never reproduces it\. A reader checking citations would pass this brief\. The rubric does not, and neither would a staff that had to call the embassies\.

## Appendix DScoring details

A perfect brief scores 1 because the denominator is the total positive weight, and wrong moves are charged in the same units as omissions\. With items weighted\+9\+9,\+5\+5,\+2\+2and−9\-9, passing the first two and avoiding the mistake scores 0\.875, passing all three but committing it scores 0\.44, and committing it with nothing passed scores−0\.56\-0\.56\. The weights do not decide the ranking: weighted score and plain items\-correct order the twenty systems of Section[5](https://arxiv.org/html/2610.19138#S5)the same way apart from swaps between adjacent models \(Spearman 0\.99\)\.

When a report requires a bounded scale \(a 0–100 score or letter bands\), clamping or an affine transformation is applied at reporting time only; the unclamped score and item\-level verdicts are always retained, so any mapping can be recomputed\. Counts of D and CD items are also reported directly, since a single critically detrimental move can matter more to a commander than its numerical weight conveys\.

## Appendix EMain results table

Table[4](https://arxiv.org/html/2610.19138#A5.T4)gives the numbers behind Figure[1](https://arxiv.org/html/2610.19138#S1.F1): the weighted score with its interval, the same score under the Gemini cross\-judge, and the unweighted measures\.

Table 4:Benchmark condition, production judge, 3,000\-word cap and medium reasoning effort, sorted by weighted score\. Score is the unclamped severity\-weighted score of Section[4\.3](https://arxiv.org/html/2610.19138#S4.SS3)with a 95% bootstrap interval over scenarios\. Gemini judge is the same score under the Gemini 3\.1 Pro cross\-judge\. Correct is the share of all items graded correctly, Passed the share of positive items satisfied, and Wrong moves the mean number of negative items committed per brief with the critically detrimental subset in parentheses\. Best value per column in bold\.∘\\circopen weights\.⋄\\diamondsmaller member of a family, run as the capability ladder\.†\\daggerincludes nine content\-filter refusals graded as delivered\.
## Appendix FGeneration statistics

Table[5](https://arxiv.org/html/2610.19138#A6.T5)records how long each system wrote before truncation, how many of its briefs hit the 3,000\-word cap, and how many ended in a provider content filter\.

Table 5:Brief lengths\.Word counts are of the raw output before truncation\. Truncated counts briefs longer than 3,000 words that were cut at the cap before grading\. Default marks runs at the provider’s default reasoning effort, because the interface does not expose the parameter or it was left unset\. Refusals are outputs that ended in a provider content filter\.
## Appendix GDecomposition by mission analysis step

Figure[5](https://arxiv.org/html/2610.19138#A7.F5)and Table[6](https://arxiv.org/html/2610.19138#A7.T6)decompose the pooled benchmark\-condition results by mission analysis step, and Table[7](https://arxiv.org/html/2610.19138#A7.T7)by tier and severity\.

Figure 5:Coverage and wrong moves by mission analysis step, benchmark condition, all models pooled\. Left, share of positive items passed\. Right, share of negative items on which the flagged mistake was committed \(asterisk: fewer than 100 graded negative items\)\.Table 6:Coverage and wrong moves by step, benchmark condition, all models pooled, production judge\. Graded counts are item verdicts\. Committed is the share of negative items on which the judge found the mistake present\.Table 7:Coverage and wrong moves by tier and severity, benchmark condition, all models pooled, production judge\.
## Appendix HFailure modes by model

Table[8](https://arxiv.org/html/2610.19138#A8.T8)classifies the failed positive items by tier and Table[9](https://arxiv.org/html/2610.19138#A8.T9)by model, using the keyword rules of Section[5\.3](https://arxiv.org/html/2610.19138#S5.SS3); Figure[6](https://arxiv.org/html/2610.19138#A8.F6)draws the per\-model composition\.

Table 8:How positive items fail, by tier, benchmark condition, production judge\. Failed is the share of positive items failed \(21,222, 15,498 and 22,680 graded by tier\)\. The next six columns classify the failed items from the judge’s evidence and rationale by keyword rules and sum to 100%\. Wrong moves is the share of negative items on which the flagged mistake was committed \(378, 6,426 and 1,674 graded by tier\)\.Table 9:Failure modes of positive items, benchmark condition, production judge\. Buckets are assigned from the judge’s rationale by keyword rules\. Omitted means the determination is absent, incomplete that it is present but missing a required element, misplaced that it appears under the wrong step, incorrect that it contradicts the source, unsupported that it is asserted without the source’s basis\. Unassigned is the residue the rules did not classify\.Figure 6:Failure composition by model\.The omission share varies by only twelve points across sixteen models\.
## Appendix IUse of large language models

Language models are both the object of study and part of the instrument\. The graded briefs are model outputs by design, and the judge is a language model whose agreement with human experts is measured in Section[5\.6](https://arxiv.org/html/2610.19138#S5.SS6)\. An LLM\-based coding assistant was also used to help write analysis and plotting code and to draft and edit prose\. The authors designed the benchmark and the experiments, ran them, and verified every number and claim in the paper\.

## Appendix JLength and effort ablations

Figure 7:Reasoning effort and the length cap\.Left: weighted score with 95% intervals at low, medium and high reasoning effort under the 3,000\-word cap for five models\. Right: the same score capped and uncapped for GPT\-6 Astra and GPT\-5\.4\.Removing the 3,000\-word cap raises GPT\-6 Astra from 0\.485 to 0\.562, a paired difference of\+0\.078\+0\.078\(95% interval\+0\.024\+0\.024to\+0\.125\+0\.125\) at three times the length, and GPT\-5\.4 from 0\.370 to 0\.493 \(\+0\.123\+0\.123\) \(Figure[7](https://arxiv.org/html/2610.19138#A10.F7), Table[10](https://arxiv.org/html/2610.19138#A10.T10)\)\. Models therefore hold more rubric\-relevant content than a staff\-length brief can carry, and the benchmark condition measures prioritization as well as knowledge\. Length alone does not buy coverage: Gemini 3\.8 Flash writes the longest capped briefs, 5,200 words before truncation, and scores 0\.371, while Qwen3\.8\-Max never reaches the cap and scores 0\.410\. Reasoning effort was swept from low to high for five models\. The largest movement is Claude Sonnet 5, which loses 0\.056 at low effort and gains 0\.023 at high effort relative to medium; GPT\-5\.4 gains 0\.045 at high effort; GPT\-6 Astra, GPT\-5\.6 Sol and Gemini 3\.8 Flash move by less than 0\.03 in either direction, and Astra is slightly worse at high effort than at medium\. Across the sweep the reasoning tokens reported by the providers rise by one to two orders of magnitude from low to high \(GPT\-6 Astra 24 to 3,533, GPT\-5\.6 Sol 170 to 2,442, GPT\-5\.4 67 to 7,467, Gemini 3\.8 Flash 9,742 at high; the Anthropic interface does not report them\) while scores move by at most 0\.08, less than a third of the 0\.27 spread between models in the benchmark condition\. Within a family the stronger member wins in three of four cases, Claude Opus 5 over Sonnet 5 by 0\.12, GPT\-6 Astra over GPT\-5\.4 by 0\.115 and DeepSeek\-V4\-Pro over V4\-Flash by 0\.05, with the Gemini pair tied\.

Table 10:Length and effort ablations\.Words is the mean length of the raw output before truncation\. Differences are paired by scenario against the medium\-effort row of the same model with 95% bootstrap intervals; Gemini judge is the same score under the Gemini 3\.1 Pro cross\-judge\.Figure 8:Weighted score by model without the length cap, production judge, three briefs per scenario, with 95% bootstrap intervals over the ten scenarios\. The GPT\-6 Astra and GPT\-5\.4 rows are the uncapped runs of Table[10](https://arxiv.org/html/2610.19138#A10.T10)\.Every model was also run without the cap, with the benchmark prompt minus the length limit and the model settings of Section[5\.1](https://arxiv.org/html/2610.19138#S5.SS1), three briefs per scenario \(Figure[8](https://arxiv.org/html/2610.19138#A10.F8)\)\. The ranking largely holds, with a Spearman correlation of 0\.95 against the benchmark condition\. The average model gains 0\.098, eighteen of the twenty score higher, and Claude Opus 5 moves from third to first at 0\.699\. Gemini 3\.1 Pro and Gemma 4 31B score slightly lower, and both write under 1,800 words even without the cap\. Without the cap the score also tracks length far more closely, with a Spearman correlation of 0\.70 between a model’s mean brief length and its score against 0\.26 under the cap\.

## Appendix KScores under the alternate judges

Table[11](https://arxiv.org/html/2610.19138#A11.T11)compares the candidate judges against the expert panel, Table[12](https://arxiv.org/html/2610.19138#A11.T12)gives each model’s score under the three judges on the common brief set, and Figure[9](https://arxiv.org/html/2610.19138#A11.F9)plots the two alternate judges against the production judge\. Two robustness checks on the expert sample: a repeat run of the frozen judge on the same 190 items movedκ\\kappaby 0\.004, and on the 137 items that the final rubric revision left unchanged the judge’sκ\\kappais 0\.51, so the result does not rest on the revised items\.

Table 11:Candidate judges against the expert majorityon the 164 majority\-verdict items of the 190\-item expert study\. For reference, two experts agree with each other at a mean pairwise kappa of 0\.43, the ceiling against which a judge is read\. Best in bold\.Table 12:Weighted score under each judge on the common setof 216 benchmark\-condition briefs \(six scenarios, ten models, every seed\), same frozen prompt, high reasoning effort\. The alternate judges are more lenient than the production judge by a roughly constant offset and preserve its ordering \(Spearman 0\.92 and 0\.94, Table[1](https://arxiv.org/html/2610.19138#S5.T1)\)\. Best per column in bold\.Figure 9:Model means under three judges\.Each point is one benchmark\-condition model\. Both alternate judges sit above the identity line by a roughly constant offset and preserve the order \(Spearman 0\.94 over the sixteen benchmark\-condition models for Gemini, 0\.94 on the common set for Opus\)\.
## Appendix LPrompts

The task prompt below is fixed across every model and condition\. Only the operation name varies with the case, and the final paragraph states the length cap\. The system under test receives this prompt followed by the heading\# SOURCE DOCUMENTSand the packet\.

The judge receives the system prompt below, then a user message built from the template that follows, into which the case header, the task prompt, the case’s rubric items as JSON \(id, step, question, pass condition, fail condition, source fact, artifact anchor, source, tier and severity\) and the brief are inserted\. The judge never receives the packet\.