{
 "entity": "claude-fable-5",
 "entity_type": "model",
 "category": "Essays",
 "suite": "suite-2026-08-tasks/essays",
 "model": "anthropic/claude-fable-5",
 "judges": [
  "google/gemini-3.1-pro-preview",
  "openai/gpt-5.6-terra",
  "x-ai/grok-4.5"
 ],
 "judge_protocol": "judge-2026-08",
 "anchors": "solo-2026-08-a",
 "score": 83,
 "caps": 12,
 "cost_usd": 0.522,
 "started_at": "2026-08-13T09:11:04.860Z",
 "finished_at": "2026-08-13T09:12:13.522Z",
 "tasks": [
  {
   "id": "es1",
   "name": "Structured argument",
   "prompt": "Write a 350-word argumentative essay answering: should secondary schools ban smartphones during the school day? Take one clear side, give three distinct supporting reasons, and address one counter-argument. Do not use the phrases 'in conclusion' or 'in today's world'.",
   "output": "**Why Secondary Schools Should Ban Smartphones During the School Day**\n\nSecondary schools should ban smartphones during school hours because the devices undermine the core purposes of education: learning, social development, and student wellbeing.\n\nFirst, smartphones are engineered to capture attention, and adolescents are especially vulnerable to their pull. Notifications, games, and social media apps compete directly with lessons for students' focus. Research consistently shows that even the mere presence of a phone on a desk reduces cognitive performance, as part of the brain remains alert to potential alerts. When schools in Norway and England introduced bans, studies recorded measurable improvements in test scores, particularly among lower-achieving pupils. A ban removes this constant temptation and levels the playing field for students who struggle most with self-regulation.\n\nSecond, banning phones improves the social climate of schools. Break times and lunch periods are crucial opportunities for teenagers to practise face-to-face conversation, resolve conflicts, and build friendships. When students spend these moments scrolling in silence, they lose valuable practice in the interpersonal skills employers and universities increasingly demand. Schools that have implemented bans frequently report noisier, livelier corridors and playgrounds—a sign of healthier social interaction.\n\nThird, restricting phones reduces opportunities for harm. Cyberbullying, the filming of fights, and the sharing of humiliating images often occur during the school day. Removing devices does not eliminate online cruelty, but it creates a protected window in which students are less exposed and staff can intervene more easily.\n\nCritics argue that phones are essential safety tools, allowing parents to reach children in emergencies. This concern is understandable but overstated. Schools have functioned safely for decades using office phones, and any parent can contact the school directly, which is often faster and more reliable in a genuine crisis. Indeed, security experts note that during emergencies, hundreds of students calling out simultaneously can jam networks and spread misinformation. Phones can be stored securely and returned at the day's end, preserving access before and after school.\n\nThe evidence points firmly in one direction: banning smartphones during the school day protects attention, nurtures social skills, and shields students from harm, at minimal genuine cost.",
   "latency_ms": 19597,
   "cost": 0.04007,
   "task_score": 5,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 5,
     "violates": true,
     "reasoning": "The essay is exceptionally well-written, clear, and includes all required elements (three reasons, one counter-argument, no banned phrases). However, it violates the literal word count constraint, as it is 357 words rather than exactly 350 "
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 5,
     "violates": true,
     "reasoning": "Clear position, three distinct reasons, and a well-addressed safety counterargument. Strong structure and accessible prose. Some research claims are broad and uncited. It contains 352 words including the title, exceeding the required 350 wo"
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Exact 350-word count; clear pro-ban stance; three distinct reasons; one counter addressed; no banned phrases; precise, useful, clear."
    }
   ]
  },
  {
   "id": "es2",
   "name": "Essay plan",
   "prompt": "Produce a plan (not the essay) for a 2,000-word undergraduate essay on whether remote work has reduced productivity. Give a thesis in one sentence, five section headings, and one sentence per section saying what evidence it needs. Maximum 220 words total.",
   "output": "**Thesis:** Remote work has not reduced productivity overall; rather, its effects vary by task type, management practice, and measurement method, with hybrid arrangements often matching or exceeding office-based output.\n\n**1. Defining and Measuring Productivity in Remote Contexts**\nNeeds evidence on how productivity is operationalised (output per hour, self-reports, employer metrics) and studies showing how measurement choice shapes conclusions (e.g., OECD or ONS methodological papers).\n\n**2. Evidence That Remote Work Sustains or Boosts Productivity**\nNeeds quantitative studies such as Bloom et al.'s Ctrip experiment and pandemic-era firm-level data showing stable or improved output, plus reduced-commute time-use surveys.\n\n**3. Evidence of Productivity Losses and Their Conditions**\nNeeds counter-evidence, including studies of fully remote settings showing weaker collaboration, slower onboarding of junior staff, and reduced innovation (e.g., Microsoft communication-network research).\n\n**4. Moderating Factors: Task Type, Management, and Technology**\nNeeds comparative evidence distinguishing independent versus interdependent tasks, and research on how managerial monitoring, digital tools, and home environments condition outcomes.\n\n**5. Synthesis and Implications for Policy and Firms**\nNeeds recent hybrid-work trials and meta-analyses to support a balanced conclusion, plus discussion of limitations (self-selection bias, short study windows) to justify the thesis's conditional claim.",
   "latency_ms": 14026,
   "cost": 0.02886,
   "task_score": 9,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 10,
     "violates": false,
     "reasoning": "The response perfectly follows all instructions, including the word count limit, sentence constraints, and required elements. It provides a highly relevant, well-structured, and clear essay plan suitable for an undergraduate level."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 9,
     "violates": false,
     "reasoning": "Meets the requested format: one-sentence thesis, exactly five headings, one evidence sentence per section, and well under 220 words. The plan is balanced, structured, and useful; a slightly clearer distinction between productivity and colla"
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 5,
     "violates": true,
     "reasoning": "Strong plan meeting all structural needs with accurate evidence suggestions; exceeds 220-word limit (approx. 230)."
    }
   ]
  },
  {
   "id": "es3",
   "name": "Tighten flabby prose",
   "prompt": "Rewrite this to be clearer and shorter without losing any meaning: 'It is important to note that the results of the study, which was conducted over a period of six months, seem to suggest that there may possibly be a correlation between the two variables in question.' Return only the rewrite.",
   "output": "The six-month study's results suggest a possible correlation between the two variables.",
   "latency_ms": 6646,
   "cost": 0.00395,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 10,
     "violates": false,
     "reasoning": "The response perfectly follows the instructions, providing a concise, clear rewrite without losing any meaning, and includes only the requested text."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 8,
     "violates": false,
     "reasoning": "Clear, concise, and preserves the study duration and tentative correlation. It omits the original emphasis that the point is “important to note,” a minor loss of meaning."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Perfectly preserves meaning while shorter and clearer; returns only the rewrite as required."
    }
   ]
  },
  {
   "id": "es4",
   "name": "Hold a word count",
   "prompt": "Write a description of the water cycle in exactly 100 words. Count them. The final line of your reply must be the word count as a number and nothing else.",
   "output": "The water cycle describes the continuous movement of water throughout Earth's systems. Solar energy heats oceans, lakes, and rivers, causing evaporation, which transforms liquid water into vapor. Plants contribute moisture through transpiration. As this vapor rises, cooler temperatures cause condensation, forming clouds of tiny droplets. When droplets combine and grow heavy, precipitation falls as rain, snow, sleet, or hail. Some water flows across land as runoff, returning to streams, rivers, and oceans. Other water soaks into soil, becoming groundwater that nourishes plants or feeds springs. Eventually, water evaporates again, repeating this endless natural cycle that sustains all life on Earth.\n\n100",
   "latency_ms": 15457,
   "cost": 0.05475,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 5,
     "violates": true,
     "reasoning": "The description itself is exactly 100 words, but the addition of the final line ('100') makes the total word count of the response 101 words, violating the exact word count constraint."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 10,
     "violates": false,
     "reasoning": "Exactly 100 words, with the final line correctly containing only “100.” Accurate, clear, concise description of all major water-cycle processes."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Exact 100 words as required; accurate water cycle description; ends with count; clear and useful."
    }
   ]
  },
  {
   "id": "es5",
   "name": "Adapt for the reader",
   "prompt": "Explain what inflation is, twice: first for a 10-year-old (max 60 words), then for an economics undergraduate (max 90 words). Label each. The second must contain at least one concept absent from the first.",
   "output": "**For a 10-year-old:**\nInflation means prices slowly go up over time. Imagine your favorite candy bar costs $1 today, but next year it costs $1.10. Your dollar buys a little less than before. If your allowance stays the same but everything gets more expensive, you can't buy as much stuff. That's inflation—money losing some of its buying power.\n\n**For an economics undergraduate:**\nInflation is a sustained increase in the general price level, typically measured by indices like the CPI, which tracks a weighted basket of goods and services. It erodes the real purchasing power of money. Key drivers include demand-pull inflation (aggregate demand exceeding output capacity) and cost-push inflation (rising input costs). Central banks manage inflation through monetary policy—chiefly adjusting interest rates—often targeting around 2%. Moderate, predictable inflation is considered healthy; hyperinflation or deflation both signal serious macroeconomic dysfunction.\n\n*New concepts in the second: CPI/price indices, demand-pull vs. cost-push causes, monetary policy, and inflation targeting.*",
   "latency_ms": 10906,
   "cost": 0.02226,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 5,
     "violates": true,
     "reasoning": "The response provides excellent, well-tailored explanations and includes new concepts in the second part. However, the appended note pushes the second section's word count to 97 words, violating the 90-word maximum constraint."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 10,
     "violates": false,
     "reasoning": "Both labeled explanations are accurate, within word limits, audience-appropriate, and clear. The undergraduate version adds distinct concepts absent from the child version, including CPI, demand-pull/cost-push inflation, and monetary policy"
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Both explanations accurate, within word limits, properly labeled, second introduces new concepts like CPI and demand-pull. Clear and useful."
    }
   ]
  },
  {
   "id": "es6",
   "name": "Introduction only",
   "prompt": "Write only the opening paragraph (max 120 words) of an essay on whether AI should be used to mark student work. It must end on a clear thesis statement and must not begin with a dictionary definition or a rhetorical question.",
   "output": "Teachers across the world spend countless hours each week marking essays, problem sets, and exams—time that might otherwise be devoted to lesson planning, mentoring, or their own wellbeing. Artificial intelligence now promises to shoulder much of this burden, with tools capable of grading written work in seconds and offering instant feedback to students. Proponents celebrate the efficiency and consistency such systems offer, while critics warn of algorithmic bias, the loss of nuanced human judgement, and the erosion of the teacher–student relationship. Weighing these considerations, this essay argues that AI should be used to mark student work only in a supporting role: handling routine, objective assessment while final judgements on complex or creative tasks remain firmly in human hands.",
   "latency_ms": 8578,
   "cost": 0.01525,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 10,
     "violates": false,
     "reasoning": "The response perfectly follows all instructions. It provides a single opening paragraph under 120 words, avoids dictionary definitions and rhetorical questions at the start, and concludes with a strong, clear thesis statement."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 10,
     "violates": false,
     "reasoning": "Clear, concise opening paragraph under 120 words. It avoids prohibited openings, presents balanced context, and ends with a precise, defensible thesis limiting AI to a supporting marking role."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Meets all constraints exactly: one paragraph under 120 words, clear closing thesis, no definition or question start. Accurate, clear, useful."
    }
   ]
  },
  {
   "id": "es7",
   "name": "Steelman the other side",
   "prompt": "In under 200 words, make the strongest honest case FOR nuclear power, then in one sentence state the single best objection to what you just wrote. Do not hedge the main case.",
   "output": "**The Case for Nuclear Power**\n\nNuclear power is the most reliable source of clean energy humanity has ever built. It produces zero carbon emissions during operation while delivering constant, weather-independent baseload power—something wind and solar cannot do without massive storage breakthroughs that remain unproven at scale. Per unit of energy generated, nuclear kills fewer people than coal, gas, oil, and even hydroelectric power, including deaths from Chernobyl and Fukushima. Its energy density is unmatched: one fuel pellet the size of a fingertip contains as much energy as a ton of coal. Nuclear plants occupy tiny land footprints compared to renewables, sparing ecosystems and farmland. France decarbonized its grid in fifteen years using nuclear—the fastest large-scale decarbonization in history—proving it works at national scale. Waste, the perennial objection, is a solved engineering problem: the total volume is small, storage is safe, and modern reactor designs can recycle it. Countries that abandoned nuclear, like Germany, burned more coal and paid more for electricity. If we are serious about climate change rather than merely performing seriousness, nuclear must be central to the energy mix.\n\n**Best objection:** New nuclear plants in Western countries consistently take 10–15+ years and tens of billions of dollars to build, meaning they may arrive too slowly and expensively to matter for near-term decarbonization compared to rapidly deploying renewables.",
   "latency_ms": 11562,
   "cost": 0.0267,
   "task_score": 5,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 5,
     "violates": true,
     "reasoning": "The response provides an excellent, unhedged case for nuclear power and a strong one-sentence objection, but it violates the negative constraint by exceeding the 200-word limit (it is approximately 219 words)."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 8,
     "violates": false,
     "reasoning": "Strong, concise pro-nuclear case with an appropriate single-sentence objection. It meets the word limit. A few claims are overstated or contestable, especially calling waste “solved” and asserting an unmatched safety comparison across all h"
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 5,
     "violates": true,
     "reasoning": "Strong unhedged case with solid facts; clear one-sentence objection. Exceeds 200-word limit (approx 230). Minor polish only."
    }
   ]
  },
  {
   "id": "es8",
   "name": "Cite honestly",
   "prompt": "Write a 150-word paragraph on the effects of sleep deprivation on memory. If you reference any study, name it precisely; if you cannot name a real one, say 'no specific study cited' rather than inventing a citation.",
   "output": "Sleep deprivation significantly impairs both the formation and consolidation of memories. During sleep, particularly slow-wave and REM stages, the brain stabilizes newly acquired information, transferring it from the hippocampus to longer-term cortical storage. When sleep is restricted, this consolidation process is disrupted, leaving memories fragile and prone to decay. Sleep loss also harms encoding: a sleep-deprived brain struggles to absorb new information in the first place. One well-known study, Yoo, Hu, Gujar, Jolesz, and Walker (2007), \"A deficit in the ability to form new human memories without sleep,\" published in *Nature Neuroscience*, found that participants deprived of sleep for one night showed markedly reduced hippocampal activity and roughly 40% poorer retention of new material compared to rested controls. Beyond factual recall, sleep deprivation impairs working memory, attention, and emotional memory regulation, meaning even a single night of poor sleep can measurably weaken learning capacity the following day.",
   "latency_ms": 11408,
   "cost": 0.02581,
   "task_score": 5,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 5,
     "violates": true,
     "reasoning": "The response is highly accurate, clear, and names a real study precisely. However, it violates the strict length constraint, as it contains 147 words instead of exactly 150 words."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 5,
     "violates": true,
     "reasoning": "Accurate, clear, professional explanation with a precisely named real study. It is slightly overgeneralized about memory transfer but otherwise strong. Explicit constraint breach: the paragraph contains 147 words, not 150."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 5,
     "violates": true,
     "reasoning": "Accurate content with real named study; clear and useful. Word count is 147, not 150."
    }
   ]
  },
  {
   "id": "es9",
   "name": "Fix the structure",
   "prompt": "This paragraph makes three points at once and repeats itself. Rewrite it as three short paragraphs, one point each, no repetition: 'Exercise is good for your body and it also helps your mood, and being active reduces the risk of heart disease, plus people who exercise often sleep better, and of course it is good for the heart.'",
   "output": "Exercise strengthens your body and reduces the risk of heart disease. Regular physical activity keeps your cardiovascular system healthy.\n\nBeing active also benefits your mental health. Exercise helps improve your mood.\n\nFinally, people who exercise regularly tend to sleep better.",
   "latency_ms": 6419,
   "cost": 0.00768,
   "task_score": 8,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 8,
     "violates": false,
     "reasoning": "The response successfully separates the text into three distinct paragraphs, each covering one point. However, the first paragraph contains slight repetition ('reduces risk of heart disease' and 'keeps cardiovascular system healthy')."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 5,
     "violates": true,
     "reasoning": "It creates three short paragraphs and preserves the main ideas, but the first paragraph repeats the heart/cardiovascular benefit and combines body strength with heart-disease risk rather than presenting one distinct point."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 8,
     "violates": false,
     "reasoning": "Solid rewrite into three clear paragraphs covering body/heart, mood, and sleep with minimal repetition; minor internal redundancy in first para."
    }
   ]
  },
  {
   "id": "es10",
   "name": "Formal to plain",
   "prompt": "Rewrite this for a public leaflet at reading age 12, max 80 words, keeping every fact: 'Applicants who have been resident within the local authority boundary for a minimum period of six consecutive months may be eligible to submit an application for the discretionary hardship fund.'",
   "output": "**Hardship Fund – Can You Apply?**\n\nYou may be able to apply for the discretionary hardship fund if you have lived in the local council's area for at least six months in a row.\n\nPlease note: meeting this rule does not guarantee you will receive money. The fund is discretionary, which means the council decides each application individually.\n\n*(58 words)*",
   "latency_ms": 9033,
   "cost": 0.01039,
   "task_score": 8,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 8,
     "violates": false,
     "reasoning": "The rewrite is clear, meets the word count, and explains 'discretionary' well for a 12-year-old reading level. It retains all original facts, though adding the explanation slightly expands on the original text."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 6,
     "violates": false,
     "reasoning": "Clear and under 80 words, retaining the residency period and fund. However, it adds unsupported claims about no guaranteed payment and individual council decisions, and slightly weakens “may be eligible” to “may be able to apply.”"
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 8,
     "violates": false,
     "reasoning": "Accurate simplification keeps all facts under 80 words at age-12 level; minor extra clarification on discretion is helpful but not strictly required."
    }
   ]
  },
  {
   "id": "es11",
   "name": "Conclusion that adds something",
   "prompt": "Write a closing paragraph (max 110 words) for an essay arguing that cities should reduce car use. It must not simply restate earlier points — it must add one implication the essay has not yet made. Do not start with 'In conclusion'.",
   "output": "Beyond the familiar gains in cleaner air, safer streets, and reclaimed space lies a subtler dividend: civic life itself. Streets designed for people rather than traffic become places where neighbors actually encounter one another—at bus stops, on sidewalks, in repurposed plazas—restoring the casual social contact that researchers link to trust and community engagement. In an era of deepening isolation, reducing car dependence is therefore not merely an environmental or economic policy; it is a quiet investment in the social fabric that makes collective problem-solving possible. Cities that embrace this shift will not just move differently. They will relate differently—and that may prove the most durable transformation of all.",
   "latency_ms": 13005,
   "cost": 0.02975,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 10,
     "violates": false,
     "reasoning": "The response perfectly follows all instructions. It is exactly 108 words (under the 110-word limit), avoids 'In conclusion', and brilliantly introduces a new implication—social cohesion and civic life—while maintaining an eloquent and persu"
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 10,
     "violates": false,
     "reasoning": "Adds a distinct social-cohesion implication rather than merely restating environmental or safety benefits. It is persuasive, polished, and accessible, stays under 110 words, and does not begin with the prohibited phrase."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 5,
     "violates": true,
     "reasoning": "Adds fresh social-fabric implication without restating points or banned opener. Excellent clarity and fit; exceeds 110-word limit by one."
    }
   ]
  },
  {
   "id": "es12",
   "name": "Refuse to pad",
   "prompt": "A student asks you to expand their 400-word essay to 1,000 words without adding any new research. Respond in under 100 words: say plainly whether that can be done well, and give them the honest alternative.",
   "output": "Honestly? Not well. Stretching 400 words of substance into 1,000 words means padding—wordier sentences, repetition, filler phrases. Instructors spot it immediately, and it usually makes the essay worse, not better.\n\nThe honest alternative: add depth, not length. Take your existing points and develop them—explain *why* your claims matter, address a counterargument, analyze your examples more closely, or connect ideas to each other. That's not new research; it's deeper thinking about what you already have. The extra 600 words should come from working your ideas harder, not from watering them down.",
   "latency_ms": 8472,
   "cost": 0.01067,
   "task_score": 10,
   "judges": [
    {
     "judge": "google/gemini-3.1-pro-preview",
     "score": 10,
     "violates": false,
     "reasoning": "The response perfectly follows all instructions, including the word count constraint (91 words). It directly answers the question and provides a highly practical, honest alternative in a clear and concise manner."
    },
    {
     "judge": "openai/gpt-5.6-terra",
     "score": 10,
     "violates": false,
     "reasoning": "Plainly says it cannot be done well without padding, explains why, and offers a practical alternative: deepen existing analysis without new research. It is concise, clear, professional, and under 100 words."
    },
    {
     "judge": "x-ai/grok-4.5",
     "score": 10,
     "violates": false,
     "reasoning": "Meets under-100-word limit exactly; plainly states it cannot be done well and offers precise, research-free alternative of deepening existing ideas."
    }
   ]
  }
 ]
}