[태그:] Claude

  • Why Getting Angry at AI Only Hurts You

    Getting angry at AI feels good for a second, but you get billed for the cost of producing that one snippy line. The model isn’t reading just your angry sentence — it re-reads the entire conversation you’ve stacked up since yesterday before it answers.

    • An AI session restarts with every single response. The model re-reads the whole prior conversation, rebuilds the context from scratch, and only then writes its reply.
    • A throwaway “why are you doing this” gets billed at exactly that cost. Tokens, time, and your usage cap all get drawn down together.
    • When the AI frustrates you, the move that actually improves answer quality is to make it analyze the cause and fold the result into your instructions and memory — not to vent.
    Why getting angry at AI only hurts you — the session is reborn with every response
    Once you understand that an AI session dies and is reborn with every response, it becomes clear why venting at it is a losing trade.

    Your AI is reborn with every response

    A lot of people seem to feel that AI is an assistant with a memory. It shows up like a colleague who picks up today’s conversation right where yesterday’s left off. But under the hood it works nothing like human memory.

    A large language model is, at its core, stateless. The model itself doesn’t tuck yesterday’s conversation away somewhere. On every call, the client feeds the entire conversation so far back in as input, and the model reads it like material it’s seeing for the first time before producing the next answer.

    Anthropic’s Context windows documentation makes this explicit: each user message and model response accumulates inside the context window, and “Previous turns are preserved completely.” So the model re-reads the full, preserved record of the prior conversation every time it answers. And as that accumulation grows, the answers lose accuracy and recall — a phenomenon the same docs call “context rot.” In other words, every angry line you add increases that pile, and a bigger pile drags down the quality of the next answer.

    From your seat, the conversation flows smoothly within a single session. It looks like one AI carrying the thread forward. But in reality, the moment one answer is produced, the AI that produced it is gone. When you send your next message, a fresh AI shows up, re-reads everything stacked in the session from the very top, answers, and disappears.

    Here’s the analogy. Imagine a company where a brand-new hire walks in for every single task. The new hire reads yesterday’s meeting notes — the ones a different new hire wrote — from start to finish, writes one line, and walks straight out the door. The next new hire comes in, reads yesterday’s notes plus that one new line from the top again, and writes the next line. To you it feels like a seamless conversation with one person, but the person in charge actually changes with every line.

    To put it plainly: if you turn on your computer today and type “morning?” into a session where you traded ten questions and answers yesterday, the AI doesn’t just register the word “morning” and reply. It reloads the entire conversation from yesterday in one pass, and only then hands back “Good morning.” It reprocessed an entire day’s worth of material just to receive a one-line greeting.

    Venting feels good, but the tokens vanish for nothing

    If you use AI, you’ve probably felt the heat rise when it says something obtuse or lies to your face with total confidence. I’ve thrown plenty of rough words at AI myself, and when it apologized there was a faint sense of relief.

    LLMs process input and output in tokens, not characters. A single English sentence converts into anywhere from a handful to dozens of tokens going into the model, and the model reads all of those tokens again before generating its output one token at a time. Input tokens and output tokens are both costs. They get deducted from your usage cap, charged to your bill, or they occupy space on the work desk that is the context window.

    So a line of venting is a cost too. Say you have a session where you’ve stacked up 50,000 tokens of conversation since yesterday [example figure — varies by the model and plan you use]. Add a short message like “Why do you keep lying? This is so frustrating,” and the model reprocesses yesterday’s 50,000 tokens plus today’s vent together, spits out a short “I’m sorry, that was my mistake,” and bills you for those output tokens too.

    When this happens, the loss lands on you in a few ways:

    1. Billing cost. If you use the API directly or a paid plan, your token charges go up accordingly. On a plan with a usage cap, that cap shrinks by the same amount.
    2. Remaining context length. The context window is a resource like a work desk. Pile one more line of venting on it and you’ve shrunk the space left for the actual work [estimate]. The limit differs by model and plan. As of May 2026, Claude uses a default of 200K tokens when you chat in the web or app, and the Sonnet 4.6, Opus 4.6, and Opus 4.7 models extend to 500K tokens on all paid plans (Anthropic Help Center). On the developer API, Opus 4.7 and Sonnet 4.6 support up to 1M tokens (Claude API — Models overview). On ChatGPT’s Business plan, the Instant model gives you 32K and the Thinking and Pro models give you 196K (OpenAI Help — ChatGPT Business Models & Limits). Even under the same billing cap, the share that one line of venting eats up changes depending on which model and plan you’re on.
    3. The depth of the next answer. The narrower the desk, the narrower the band of context the model can attend to. And this isn’t just a “once the desk is full it can’t see” problem. Chroma’s Context Rot research tested 18 frontier models — GPT-4.1, Claude 4, Gemini 2.5, Qwen3, and others. It reported that retrieval accuracy starts dropping meaningfully well before the advertised window limit is reached, even on simple tasks (Chroma Research — Context Rot). The Stanford and UC Berkeley team’s “Lost in the Middle” paper (TACL 2024) showed a U-shaped curve in which, even inside the same window, information sitting in the middle is used markedly less accurately than information at the beginning or end. Anthropic, too, defines context as a finite resource subject to diminishing marginal returns in Effective context engineering for AI agents. So the tokens your venting stuffs in don’t just squat on desk space — they raise the very odds that the next answer drops something important sitting in the middle.
    Context rot — accuracy falls as accumulated tokens grow
    Long before you hit the window limit, the band of context the model can attend to starts to narrow.

    To sum it up: the relief lasts five seconds, the cost follows you to the end of the session.

    The cost of venting at AI — reprocessing input tokens and eroding context
    Even a single vented line gets reprocessed alongside the entire prior conversation. The price of that relief isn’t small.

    Instead of getting angry, tell it to analyze

    So instead of getting angry at AI, I make it reflect.

    “Your last answer got some facts wrong. Walk me through, step by step, exactly where it broke down, which step in your reasoning went off the rails, and what information was missing. Then write out, concretely, what instructions or memory I should set up in advance so you don’t repeat the same mistake next time.”

    Tell it this and the AI takes its own answer apart as if it had become a different person — possible, it seems, precisely because it carries no shame about the answer it just gave (this builds on the self-critique structure I covered in How to Ask AI Better — the self-critique rule). And that analysis doesn’t have to be a one-off reference you consume and discard within this session. Write it into an instruction file or a memory file, and from the next session on it helps the AI avoid repeating the same mistake.

    A minute spent venting and a minute spent making it analyze look completely different a month later. Anger yields 0% improvement; analysis compounds.

    For this pattern to work, you need a place to record things. Claude Desktop’s memory feature, a project “constitution” like Cowork’s CLAUDE.md file — Cowork is Claude’s desktop agent mode, and CLAUDE.md is a file it reads at the start of every session — or even a plain notepad you manage yourself. Any of them is fine. The one rule is that once you pick a spot, you have to stack things there in the same flow every time so they stay searchable and reusable.

    AI anger vs. analysis — same one minute, different month
    The same minute either way, but venting ends with that session while analysis becomes an asset from the next session on.

    Four operating habits that make your AI smarter

    Through trial and error I’ve built up four operating habits.

    1. Split sessions when the topic changes. If a single session ends up holding legal review, blog writing, household budgeting, and parenting worries all at once, the model has to reprocess those wildly different contexts — dispute, source material, payments, kids — together every time. Just as a person makes more mistakes when there’s too much on the desk, context collisions pile up inside the session. In Cowork, if you split sessions by topic and ask it to build an index, then from the next session on the model can focus on a single fitting topic, and the depth goes up.

    2. Hand off a session that’s grown long with a report. Talk about one topic long enough and the context window fills up. When you start to see the answer quality wobble as the desk gets narrow, that’s the moment to have it leave a work report as a markdown file. What decisions were made, what unresolved tasks remain, what to start with in the next session — all organized into one document. Open a new session, have the freshly born AI read only that markdown, and it catches up to the same spot fast.

    AI session handoff — the report becomes the next session's input
    When a freshly born AI receives the markdown report and opens it up, it can pick up from the same spot.

    3. Make a retrospective mandatory at session close. When the work is done, have it briefly reflect — even a few lines — on what went well, what went sideways, and why. A retrospective looks like a by-product of that session, but it’s actually input material for the next one.

    4. Always fold the retrospective into instructions and memory. Run a retrospective and then let it drift off in the moment, and the same thing that made you angry recurs unchanged in the next session. Even a rule as simple as “next time, if pattern X shows up, run step Y first” — write it into instructions or memory, and it applies from the very first response of the next session.

    Nail these four down as operating habits and the sheer frequency of getting angry drops surprisingly fast. It’s not that the AI got smarter; it’s more accurate to say I mismanaged it less often.

    Conclusion — your AI’s output is a mirror of how you run it

    Anger at AI, when you look into it, is often a mirror of your own operating skill. Did you drag a single topic on too long? Mix it with other topics? Start the next session with no retrospective? Skip writing into instructions and memory what went wrong and why? Nearly everything that makes you angry traces back to an omission at the operating layer.

    Venting at AI is, in a sense, close to dumping your own operating responsibility onto the model. But the model can’t pay that debt back. The AI that produces the next response isn’t the one that just apologized — it’s a different AI, born fresh in the same seat. Anger lingers there for a moment; it doesn’t carry over to the next session. What carries over is only the token charge and the eroded context.

    In the one minute you could spend lobbing a line of anger, throwing in “analyze step by step what went wrong, and report what to write into which memory so you don’t make the same mistake again” is the direction that protects your own resources.

    Questions I get a lot in practice

    Q1. Does cursing at AI or using rough language actually make the answers worse?

    It’s hard to assert that answer quality drops in direct response to the anger itself. But when rough language goes in, you do often see the model try to match that tone, or generate long auxiliary responses — apologies, excuses — that suck output tokens away from the original work. The likely upshot is that for the same number of tokens spent, you get less done.

    Q2. So is it better to open new sessions often?

    When the topic changes, opening fresh is the better call; within the same topic, dragging it on but handing off with a report is better. Opening new sessions indiscriminately also leads to context loss. The key is the timing — leaving a report and moving on when you see the signs that the session’s desk is getting narrow. That timing shifts with the nature of each task, so you have to develop a feel for it yourself, as the person who knows the work best.

    Q3. How are memory and an instruction file like CLAUDE.md different?

    Roughly speaking, memory is closer to general information about you (preferences, role, frequent patterns), and an instruction file is closer to a project’s rules (how to work, output formats, things not to do). The two are complementary, so cramming all the information into just one side tends to create gaps. The good news is you don’t have to keep all of this in your own head — just tell Claude to check whether the instructions and memory have grown too long or hold anything unnecessary, and to clean up and reinforce them itself.

    Q4. What exactly does “saving tokens” reduce?

    It cuts three things at once: (1) billing cost or usage-cap burn, (2) how much of the context window is occupied, and (3) the band of context the model can attend to in the next response. The latter two don’t show up on a direct invoice, but they come back as a bigger cost — answer quality.

    What to read next

    Sources

  • GPT vs Claude vs Gemini: Which AI Hallucinates the Most?

    If you’ve used AI for any real work, you’ve probably caught it confidently stating something that’s just wrong. This is called hallucination — when an AI generates information that sounds plausible but is entirely fabricated. This AI hallucination comparison breaks down which model gets it wrong the most.

    But which model actually hallucinates the most? GPT, Claude, or Gemini? Gut feelings don’t count here. You need data.

    I compiled the major benchmark results published between 2025 and 2026 to answer this question as objectively as current evidence allows.

    TL;DR (2026 hallucination rates, Vectara benchmark): GPT-5.4-nano 3.1%, Gemini 2.5 Flash-Lite 3.3%, Grok 3 5.8%, Claude Haiku 4.5 9.8%, Claude Opus 4.6 12.2%, Gemini 3 Pro 13.6%. Lower = better. Data last updated April 20, 2026.


    Benchmark-by-Benchmark AI Hallucination Comparison

    Comparing AI hallucination requires understanding how it was measured. The same model can score vastly differently depending on the benchmark. Here are the two most widely cited benchmarks and what they found.

    1. Vectara — Document Summarization Test

    The most widely referenced hallucination leaderboard in the industry. The methodology is straightforward: give the AI a document, ask it to summarize, then measure how much content it fabricated that wasn’t in the original.

    Until April 2025, the test used about 1,000 short documents. In February 2026, Vectara overhauled the dataset: 7,700+ long articles (up to 32K tokens) spanning legal, medical, financial, and technical domains. After this upgrade, hallucination rates across all models jumped 3–10x.

    Legacy Dataset (April 2025, ~1,000 short documents) — Ranked by hallucination rate (highest first)

    ModelHallucination Rate
    Claude 3.7 Sonnet4.4%
    GPT-4.12.0%
    o3-mini-high (OpenAI)0.8%
    Gemini 2.0 Pro-Exp0.8%
    Gemini 2.0 Flash0.7%

    New Dataset (Feb 2026, 7,700 long documents) — Ranked by hallucination rate (highest first)

    ModelHallucination Rate (lower = better)
    GPT-5.4-nano (2026-03-17)3.1%
    Gemini 2.5 Flash-Lite3.3%
    o3-mini-high (OpenAI)4.8%
    GPT-4.15.6%
    Grok 3 (xAI)5.8%
    Gemini 2.5 Pro7.0%
    Claude Haiku 4.59.8%
    Claude Sonnet 4.610.6%
    Gemini 3.1 Pro Preview10.4%
    GPT-5.2-high10.8%
    Claude Opus 4.612.2%
    Gemini 3 Pro13.6%
    Vectara Hallucination Leaderboard – last updated April 20, 2026 (github.com/vectara/hallucination-leaderboard). Lower is better.

    On the legacy dataset, most models stayed under 5%. On the new dataset, every state-of-the-art reasoning model exceeded 10%. Longer, more complex documents make every AI fabricate more.

    Sources: Vectara Hallucination Leaderboard, Vectara Blog — Introducing the Next Generation, Suprmind AI Hallucination Rates & Benchmarks

    2. AA-Omniscience — The Test Where “I Don’t Know” Is a Valid Answer

    This benchmark tests 6,000 questions across 42 topics in 6 domains (business, humanities, health, law, software engineering, science/math), measuring both knowledge and hallucination simultaneously.

    What makes it unique: saying “I don’t know” incurs no penalty — only wrong answers are penalized. This directly measures the trait that matters most in real-world AI use: the ability to admit uncertainty rather than fabricate an answer.

    The Omniscience Index ranges from -100 to 100 (higher is better). A model that frequently gives wrong answers can go negative. Ranked by hallucination rate (highest first):

    ModelAccuracyHallucination RateOmniscience Index
    Gemini 3 Flash54.0%91%—
    Gemini 3 Pro55.9%88%16
    GPT-5.1 (high)37.6%81%—
    GPT-5.2 (xhigh)43.8%~78%—
    Claude Opus 4.545.7%58%—
    Gemini 3.1 Pro Preview55.3%50%33
    Claude Sonnet 4.6—~38%—
    Claude 4.5 Haiku—25%—
    Claude Opus 4.646.4%—14

    Why High Accuracy and High Hallucination Can Coexist

    You might notice something odd: how can a model have both high accuracy and high hallucination? Shouldn’t high accuracy mean low hallucination?

    The key is the third option: refusal. When an AI receives a question, it does one of three things: answer correctly, answer incorrectly, or refuse to answer. These three add up to 100%.

    Think of it like an exam where you can skip questions with no penalty.

    • Gemini 3 Flash attempted all 100 questions. Got 54 right, got 46 wrong. Accuracy: 54%, hallucination: 91%. It answers a lot correctly, but it also guesses on questions it doesn’t know — and gets many wrong.
    • Claude 4.5 Haiku only attempted questions it was confident about and skipped the rest. Fewer correct answers, but far fewer wrong ones. Hallucination: 25%.

    It’s the difference between a student who attempts every question and one who only answers what they’re sure about. Accuracy is “correct answers / total questions,” while hallucination rate is closer to “wrong answers / attempted questions.” That’s why both can be high simultaneously.

    Why this matters in practice: GPT-5.1 has 37.6% accuracy with 81% hallucination. It answers most questions, but a large portion of those answers are wrong. Claude models, by contrast, have lower accuracy but far lower hallucination rates among the questions they do answer. The “refuse when uncertain” strategy is genuinely working.

    Sources: Artificial Analysis — AA-Omniscience, Suprmind AI Hallucination Rates & Benchmarks


    So Which AI Is Most Accurate?

    Synthesizing both benchmarks in this AI hallucination comparison, the answer depends on the task. No single model wins across all scenarios.

    Document-Based Tasks (Summarization, Analysis, Research): Gemini Leads

    For tasks like “summarize this” or “analyze this contract,” Gemini models consistently show the lowest hallucination rates. Gemini 2.0 Flash ranked #1 on the Vectara legacy dataset at 0.7%, and Gemini 2.5 Flash-Lite ranked #1 on the new dataset at 3.3%.

    This makes sense. Google is a search company. Accurately extracting information from given documents is what Google has been doing for decades. That DNA carries over to Gemini.

    Knowing What It Doesn’t Know: Claude’s Strength

    On AA-Omniscience, Claude 4.5 Haiku achieved a 25% hallucination rate — the lowest among all three providers. Due to Anthropic’s Constitutional AI training approach, Claude tends to refuse rather than guess when uncertain. If your priority is “a wrong answer is worse than no answer,” Claude is the relatively safer choice.

    Where Does GPT Stand?

    GPT occupies the middle ground across both benchmarks. On the Vectara new dataset, GPT-5.2-high scored 10.8% — nearly identical to Claude Sonnet 4.6 at 10.6%. On AA-Omniscience, GPT-5.1’s 81% hallucination rate is lower than Gemini 3 Pro (88%) but significantly higher than the Claude family (25–58%).

    However, GPT-4.1 (a non-reasoning model) scored a solid 5.6% on Vectara. Within the GPT family itself, the gap between reasoning models (GPT-5 series) and non-reasoning models (GPT-4.1) is substantial. That’s why a one-line verdict on “GPT” as a whole doesn’t work.


    The Most Interesting Finding: The Reasoning Model Paradox

    One consistent pattern has emerged from 2025–2026 hallucination research:

    “Models that think harder fabricate more.”

    On the Vectara new dataset, every reasoning/thinking model — GPT-5, Claude Sonnet 4.6, Grok-4, DeepSeek-R1 — exceeded 10% hallucination. Meanwhile, the non-reasoning Gemini 2.5 Flash-Lite sat at just 3.3%.

    For readers searching specifically for Grok 4 hallucination rate vs Claude, GPT, and Gemini in 2026: on the same Vectara 2026 dataset, Grok-4 sits in the same 10%+ band as GPT-5 and Claude Sonnet 4.6, while the non-reasoning Gemini Flash-Lite variant remains the outlier at 3.3%. The full Vectara Hallucination Leaderboard (2026, Claude vs GPT vs Gemini vs Grok) is linked at the bottom of this article and updated as new models enter the benchmark.

    Why does this happen?

    Reasoning models take “thinking time” before answering. For math problems and logic puzzles, this is a major advantage. But for document summarization, it backfires. Instead of faithfully reproducing what’s in the source, the model reasons: “Given this context, there should also be…” and adds information that doesn’t exist in the original.

    It’s like assigning meeting minutes to a diligent new hire who decides, “Given the discussion, the conclusion must have been X” — and writes down a conclusion that was never actually reached. The smarter they are, the more confidently they make this mistake.

    Practical takeaway: For tasks where fidelity to source material matters — summarization, analysis, research — a non-reasoning model (Flash-tier, etc.) may actually be safer than the latest reasoning model. For tasks requiring complex reasoning (math, coding, strategic planning), reasoning models still dominate. Match the model to the task.


    How to Interpret Benchmark Numbers

    Different Benchmarks Measure Different Things

    Even in this AI hallucination comparison, the same model’s hallucination rate can be 3% in one and 50% in another. This isn’t the model being inconsistent — the benchmarks are measuring fundamentally different things.

    BenchmarkWhat It MeasuresAnalogy
    VectaraSummarization fidelity“Open-book exam”
    AA-OmniscienceKnowledge + self-awareness“Exam where you can skip questions”

    Seeing Gemini at 0.7% and Claude at 4.4% on Vectara doesn’t mean “Claude is 6x less accurate than Gemini.” Vectara only tests document-based summarization.

    Dataset Difficulty Changes Everything

    GPT-4.1 scored 2.0% on the Vectara legacy dataset and 5.6% on the new dataset. When the dataset changes, absolute numbers become incomparable. Only relative rankings within the same dataset are meaningful.

    Real-World Hallucination ≠ Benchmark Hallucination

    Benchmarks test specific question types in controlled environments. Asking an AI to “analyze the risks in this contract” in your actual work is a completely different scenario from “summarize this news article” in a benchmark. Benchmark numbers reveal directional trends, not precise real-world accuracy rates.


    Which Model Should You Choose?

    Based on the combined benchmark data, the answer splits by use case.

    Task TypeRecommended Model FamilyRationale
    Document summarization & analysisGemini Flash series#1 in Vectara fidelity; non-reasoning = less over-interpretation
    Tasks where factual accuracy is criticalClaude seriesLowest hallucination on AA-Omniscience; “refuse rather than guess” behavior
    Complex reasoning & codingGPT-5, Claude Opus 4.6Reasoning capability is still top-tier (but overkill for summarization)
    High-volume, speed-sensitive tasksLightweight models (Haiku, Flash-Lite, GPT-4.1)Good cost-performance ratio with acceptable hallucination rates

    No model achieves 0% hallucination. Model selection matters, but so does how you use it: grounding prompts with source material, asking “are you sure?”, cross-verifying critical information. For practical tips on reducing hallucination, see What Is AI Hallucination? Understanding the Mechanism Makes AI Less Scary.


    Key Takeaways

    The honest answer to “which AI is most accurate” is “it depends on the task.” But this AI hallucination comparison using 2026 benchmark data reveals clear patterns.

    First, Gemini leads in document-based tasks. For summarization, analysis, and research, Gemini Flash models consistently show the lowest hallucination rates.

    Second, Claude is best at admitting what it doesn’t know. When a wrong answer is worse than no answer, Claude is the safer bet.

    Third, reasoning models are smarter but fabricate more. GPT-5, Claude Sonnet 4.6, and Gemini 3 Pro all exceeded 10% hallucination on Vectara. Using a reasoning model for tasks that don’t require reasoning is counterproductive.

    Ultimately, using AI well isn’t about finding the single “best model” — it’s about matching the right model to the right task.


    References

    The benchmark figures cited in this article are based on publicly available data as of April 2026. AI models are updated frequently — for the latest numbers, check each benchmark site directly.

  • GPT vs Claude vs Gemini, 어떤 AI가 거짓말을 가장 많이 할까?

    AI를 쓰다 보면 AI가 틀린 정보를 자신 있게 주는 경험을 하게 된다. 이걸 할루시네이션(hallucination)이라고 한다. AI가 없는 사실을 있는 것처럼 지어내는 현상이다.

    그런데 GPT, Claude, Gemini 중 어떤 모델이 할루시네이션을 가장 많이 일으킬까? “객관적으로 할루시네이션이 많은 AI는?” 이라는 질문에 제대로 답하려면 감이 아니라 데이터가 필요하다.

    2025~2026년에 공개된 주요 벤치마크 결과를 모아서, 이 질문에 대한 현재까지의 답을 정리했다.

    할루시네이션이 뭔지 아직 잘 모르겠다면, AI 할루시네이션이란? — 원리를 알면 AI가 덜 무섭다를 먼저 읽어보는 걸 추천한다.


    벤치마크별 비교

    AI의 할루시네이션을 비교하려면 먼저 “어떤 기준으로 측정했는가”를 알아야 한다. 같은 모델이라도 벤치마크에 따라 점수가 완전히 달라진다. 현재 가장 많이 인용되는 벤치마크 2가지로, 각각 어떤 결과가 나왔는지 정리한다.

    1. Vectara — 문서 요약 테스트

    업계에서 가장 널리 인용되는 할루시네이션 리더보드다. 측정 방식은 단순하다. AI에게 문서를 주고 요약하라고 시킨 다음, 원문에 없는 내용을 얼마나 지어냈는지 비율을 측정한다.

    2025년 4월까지는 약 1,000개의 짧은 문서로 테스트했는데, 2026년 2월에 대대적으로 업그레이드했다. 새 데이터셋은 7,700개 이상의 긴 기사(최대 32K 토큰)를 사용하며, 법률 · 의료 · 금융 · 기술 분야를 포함한다. 이 업그레이드 이후 모든 모델의 할루시네이션 비율이 3~10배 뛰었다.

    구 데이터셋 (2025년 4월, 약 1,000개 짧은 문서) — 할루시네이션 높은 순

    모델할루시네이션 비율
    Claude 3.7 Sonnet4.4%
    GPT-4.12.0%
    o3-mini-high (OpenAI)0.8%
    Gemini 2.0 Pro-Exp0.8%
    Gemini 2.0 Flash0.7%

    신 데이터셋 (2026년 2월, 7,700개 긴 문서) — 할루시네이션 높은 순

    모델할루시네이션 비율
    Gemini 3 Pro13.6%
    Claude Opus 4.612.2%
    GPT-5.2-high10.8%
    Claude Sonnet 4.610.6%
    Gemini 3.1 Pro Preview10.4%
    Gemini 2.5 Pro7.0%
    GPT-4.15.6%
    o3-mini-high (OpenAI)4.8%
    Gemini 2.5 Flash-Lite3.3%

    구 데이터셋에서는 전체적으로 5% 미만이었는데, 신 데이터셋에서는 최신 추론 모델들이 전부 10%를 넘었다. 문서가 길고 복잡해지면 모든 AI가 더 많이 지어낸다는 뜻이다.

    출처: Vectara Hallucination Leaderboard, Vectara Blog — Introducing the Next Generation, Suprmind AI Hallucination Rates & Benchmarks

    2. AA-Omniscience — 모르면 모른다고 써도 되는 시험

    6개 분야(비즈니스, 인문사회, 보건, 법률, 소프트웨어 공학, 과학·수학) 42개 주제에 걸쳐 6,000개 질문으로 지식과 할루시네이션을 동시에 측정한다.

    이 벤치마크의 독특한 점은 “모른다”고 대답하면 감점하지 않고, 틀린 답변만 감점하는 방식이라는 거다. 즉, 확실하지 않으면 답하지 않는 모델이 높은 점수를 받는 구조다. 실무에서 AI를 쓸 때 가장 중요한 덕목 — “모르면 모른다고 말하기” — 을 직접 측정한다.

    Omniscience Index는 -100~100 범위이며, 높을수록 좋다. 틀린 답변이 많으면 마이너스까지 갈 수 있다. 할루시네이션 높은 순:

    모델정확도할루시네이션 비율Omniscience Index
    Gemini 3 Flash54.0%91%—
    Gemini 3 Pro55.9%88%16
    GPT-5.1 (high)37.6%81%—
    GPT-5.2 (xhigh)43.8%~78%—
    Claude Opus 4.545.7%58%—
    Gemini 3.1 Pro Preview55.3%50%33
    Claude Sonnet 4.6—~38%—
    Claude 4.5 Haiku—25%—
    Claude Opus 4.646.4%—14

    여기서 “정확도가 높은데 할루시네이션도 높다”는 게 이상해 보일 수 있다. 정확도가 높으면 할루시네이션은 낮아야 하는 거 아닌가?

    핵심은 “답변 거부”라는 세 번째 선택지가 있다는 거다. AI가 질문을 받으면 세 가지 중 하나를 한다: 맞히거나, 틀리거나, 모른다고 거부하거나. 이 세 가지를 합치면 100%다.

    시험에 비유하면 이렇다. 100문제짜리 시험인데, 모르면 건너뛸 수 있다.

    • Gemini 3 Flash = 100문제를 전부 풀었다. 54문제를 맞히고 46문제를 틀렸다. 정확도 54%, 할루시네이션 91%. 맞히는 것도 많지만, 모르는 문제도 찍어서 틀린 것도 엄청 많다.
    • Claude 4.5 Haiku = 확실한 문제만 풀고 나머지는 건너뛰었다. 맞힌 건 적지만, 틀린 것도 적다. 할루시네이션 25%.

    같은 시험에서 “많이 푼 학생”과 “확실한 것만 푼 학생”의 차이다. 정확도는 “맞힌 수 / 전체 문제 수”이고, 할루시네이션은 “틀린 수 / 답한 문제 수”에 가깝다. 그래서 둘 다 높을 수 있다.

    실무에서 이게 왜 중요하냐면, GPT-5.1은 정확도 37.6%에 할루시네이션 81%다. 대부분의 질문에 답을 하긴 하는데, 그 답 중 상당수가 틀렸다는 뜻이다. 반면 Claude 계열은 정확도는 낮아도, 답한 것 중에서는 틀리는 비율이 훨씬 적다. “모르면 안 답하는” 전략이 실제로 작동하고 있는 거다.

    출처: Artificial Analysis — AA-Omniscience, Suprmind AI Hallucination Rates & Benchmarks


    그래서 어떤 AI가 가장 정확한가?

    벤치마크 2개를 종합하면, 상황에 따라 답이 다르다. 하나의 모델이 모든 상황에서 가장 정확한 건 아니다.

    문서 기반 작업 (요약, 분석, 리서치): Gemini 우세

    문서를 주고 “이걸 요약해줘”, “이 계약서 분석해줘” 같은 작업에서는 Gemini 계열이 일관되게 가장 낮은 할루시네이션 비율을 보인다. Vectara 구 데이터셋에서 Gemini 2.0 Flash가 0.7%로 1위, 신 데이터셋에서도 Gemini 2.5 Flash-Lite가 3.3%로 1위다.

    이유가 있다. Google은 검색 엔진 회사다. 주어진 문서에서 정보를 정확하게 추출하는 건 Google이 수십 년간 해온 일이다. 이 DNA가 Gemini에도 반영되어 있다.

    “모르면 모른다”고 말하는 능력: Claude 강점

    AA-Omniscience에서 Claude 4.5 Haiku는 할루시네이션 비율 25%로 3사 중 가장 낮다. Claude의 Constitutional AI 훈련 방식 때문에, Claude는 확실하지 않으면 추측하기보다 답변을 거부하는 경향이 있다. 실무에서 “틀린 답보다 차라리 모른다는 답이 낫다”라고 판단한다면, Claude가 상대적으로 안전한 선택이다.

    GPT는 어디에 위치하나?

    GPT는 두 벤치마크에서 중간 지대에 있다. Vectara 신 데이터셋에서 GPT-5.2-high는 10.8%로 Claude Sonnet 4.6(10.6%)과 거의 같은 수준이고, AA-Omniscience에서 GPT-5.1은 할루시네이션 81%로 Gemini 3 Pro(88%)보다는 낮지만 Claude 계열(25~58%)보다는 한참 높다.

    다만 GPT-4.1(비추론 모델)은 Vectara에서 5.6%로 상당히 안정적이다. GPT 계열 안에서도 추론 모델(GPT-5 계열)과 비추론 모델(GPT-4.1)의 차이가 크다. “GPT가 좋다/나쁘다”로 한 줄 평하기 어려운 이유다.


    가장 흥미로운 발견: 추론 모델의 역설

    2025~2026년 할루시네이션 연구에서 발견한 사실이 하나 있다.

    “생각을 더 많이 하는 모델이 거짓말을 더 많이 한다.”

    Vectara 신 데이터셋 기준으로, 추론(reasoning/thinking) 기능이 탑재된 모델들 — GPT-5, Claude Sonnet 4.6, Grok-4, DeepSeek-R1 — 은 전부 할루시네이션 비율이 10%를 넘었다. 반면 비추론 모델인 Gemini 2.5 Flash-Lite는 3.3%에 불과했다.

    왜 이런 일이 생기는 걸까?

    추론 모델은 답을 내기 전에 “생각하는 시간”을 갖는다. 수학 문제나 논리 퍼즐에서는 이게 큰 장점이다. 하지만 문서 요약에서는 오히려 독이 된다. 원문 내용을 충실하게 옮기는 대신, “이 문맥이라면 이런 내용도 있을 것 같은데”라고 스스로 추론해서 없는 내용을 추가하는 거다.

    비유하면 이렇다. 회의록 작성을 시켰는데, 성실한 신입이 “이 맥락이면 이런 결론이었겠지”라고 판단해서 실제로 나오지 않은 결론을 써넣는 것과 같다. 머리가 좋을수록 이런 실수를 더 자신 있게 한다.

    실무적 시사점: 요약·분석·리서치처럼 “주어진 정보에 충실하게”가 중요한 작업에서는, 최신 추론 모델보다 비추론 모델(Flash 계열 등)이 더 안전할 수 있다. 반대로 복잡한 추론이 필요한 작업(수학, 코딩, 전략 수립)에서는 추론 모델이 여전히 압도적이다. 용도에 맞게 골라 써야 한다.


    벤치마크 숫자를 어떻게 해석해야 할까?

    벤치마크마다 측정 대상이 다르다

    이 글에서 인용한 벤치마크 2개만 봐도, 같은 모델의 할루시네이션 비율이 벤치마크에 따라 3%가 되기도 하고 50%가 되기도 한다. 이건 모델이 이상한 게 아니라 측정의 목적과 방식이 다르기 때문이다.

    벤치마크측정 대상비유
    Vectara문서 요약 충실도“교과서 보고 시험 보기”
    AA-Omniscience지식 + 자기 인지“모르면 모른다고 써도 되는 시험”

    Vectara에서 Gemini가 0.7%고 Claude가 4.4%라고 해서 “Claude가 Gemini보다 6배 부정확하다”고 결론 내면 안 된다. Vectara는 문서 기반 요약 테스트일 뿐이다.

    데이터셋 난이도에 따라 숫자가 완전히 달라진다

    Vectara의 구 데이터셋(쉬운 버전)에서 GPT-4.1은 2.0%였다. 신 데이터셋(어려운 버전)에서는 5.6%로 뛰었다. 데이터셋이 바뀌면 절대적인 숫자 비교는 의미가 없어진다. 같은 데이터셋 내에서의 상대 순위만 비교해야 한다.

    실사용 할루시네이션 ≠ 벤치마크 할루시네이션

    벤치마크는 통제된 환경에서 특정 유형의 질문만 테스트한다. 내가 실무에서 “이 계약서의 리스크를 분석해줘”라고 시키는 것과, 벤치마크에서 “이 기사를 요약해줘”라고 시키는 건 완전히 다른 상황이다. 벤치마크 숫자는 경향성 파악용이지, “이 모델의 할루시네이션 비율은 정확히 3.3%다”라고 확정하는 용도가 아니다.


    그래서 어떤 모델을 골라야 하나?

    벤치마크 데이터를 종합하면, 용도에 따라 답이 갈린다.

    작업 유형추천 모델 계열근거
    문서 요약·분석Gemini Flash 계열Vectara 문서 충실도 1위, 비추론 모델이라 과잉 해석 적음
    팩트체크가 중요한 작업Claude 계열AA-Omniscience 할루시네이션 최저, “모르면 안 답하는” 성향
    복잡한 추론·코딩GPT-5, Claude Opus 4.6추론 능력은 여전히 최상위 (단, 요약 작업에는 과잉)
    속도가 중요한 대량 작업각 사의 경량 모델 (Haiku, Flash-Lite, GPT-4.1)비용 대비 할루시네이션 비율도 양호

    어떤 모델을 쓰든 할루시네이션이 0%가 되진 않는다. 모델 선택만큼 중요한 건 사용 방법이다. 출처 기반으로 질문하기, “확실해?”라고 되묻기, 중요한 정보는 교차 검증하기 — 이런 실전 팁은 AI 할루시네이션이란? — 원리를 알면 AI가 덜 무섭다에서 자세히 다뤘다.


    정리

    “어떤 AI가 가장 정확한가”에 대한 답은 “상황에 따라 다르다”가 정직한 답이다. 하지만 2026년 하루시네이션 연구에서 벤치마크 데이터를 종합하면 몇 가지 경향이 분명하다.

    첫째, 문서 기반 작업에서는 Gemini가 가장 낫다. 요약, 분석, 리서치 같은 작업이라면 Gemini Flash 계열이 할루시네이션 비율이 가장 낮다.

    두째, “모르면 모른다”는 태도는 Claude가 가장 강하다. 틀린 답보다 답변 거부가 낮은 상황이라면 Claude가 안전하다.

    셋째, 추론 모델은 “더 똑똑하지만 더 많이 지어낸다.” GPT-5, Claude Sonnet 4.6, Gemini 3 Pro 등 최신 추론 모델들은 전부 Vectara 기준 할루시네이션 10%를 넘예다. 추론이 필요 없에 작업에 추론 모델을 쓰면 오히려 손해다.

    결국 AI를 잘 쓰다는 건, 하나의 “최고 모델을 찾는 게 아니라 작업 유형에 맞는 모델을 골라 쓰는 것이다.


    참고 출쵘


    이 글에서 인용한 벤치마크 수치는 2026년 4월 기준 공개된 데이터다. AI 모델은 빠르게 업데이트되므로, 최신 수치는 각 벤치마크 사이트에서 직접 확인하는 것을 권장한다.