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  • Dario Amodei on Policy for the AI Exponential: Anthropic’s Plan for AI Regulation, Job Displacement, Civil Liberties, and Democratic Leadership

    In June 2026, Anthropic CEO Dario Amodei published “Policy on the AI Exponential”, a wide-ranging essay arguing that the gap between how fast AI is advancing and how slowly policy moves has become dangerous, and that the window to close it is open right now. He opens with a memorable image from The Lord of the Rings: the Hobbits trying to rouse Treebeard, the ancient tree who takes a full day just to say hello, to defend his forest before it is cut down. That mismatch in speed, he writes, is exactly the relationship between AI and our political institutions. This post breaks the essay down in full and adds analysis of where the argument lands.

    TLDR

    Amodei argues that AI’s scaling laws point toward “powerful AI,” a country of geniuses in a datacenter, within a few years, while legislation still moves on a timescale of years. For most of the last few years, safety advocates including Anthropic pushed only for optionality-preserving moves like transparency rules, chip export controls, and labor data collection, because the risks were not yet concrete. He says that has changed: events like Claude Mythos Preview proved frontier models are now tools of national strategic consequence, and the time for binding regulation has arrived. The essay covers five policy areas. First, regulation and public safety, where he proposes an FAA-style regime of mandatory third-party testing of frontier models above a compute threshold across four risks (cybersecurity, biological weapons, loss of control, and automated R&D), with government power to block unsafe deployments. Second, macroeconomics and tax policy, where AI could deliver hypergrowth and severe, enduring job displacement at the same time, demanding measurement, pro-employment incentives, and possibly UBI or universal capital accounts. Third, accelerating AI’s positive impact, where the danger is regulators like the FDA being too slow rather than too lax, and biomedical approval needs reform. Fourth, the state and civil liberties, where AI could become the ultimate tool of autocracy through autonomous weapons and mass surveillance, requiring new accountability rules, a domestic ban on autonomous weapons, closing the data broker loophole, and public rights to AI advice. Fifth, securing leadership by democracies through a values-based global coalition that controls the AI supply chain, coordinates on risk, shares benefits, and rejects AI-powered repression. He closes by rejecting the idea that public concern about AI is a PR problem to be marketed away, calling it democratic accountability working as it should.

    Thoughts

    The most important move in this essay is structural, not technical. Amodei is explicitly retiring the “preserve optionality” posture that defined Anthropic’s policy work through 2025 and replacing it with a call for binding rules. For years the argument from safety-minded labs was that the risks were too speculative to legislate against without doing more harm than good, an idea he grounds in the Collingridge dilemma and the Hayekian point that regulators lack the information to make good calls. That was a defensible hedge. What is striking here is the claim that the hedge has expired. He is saying the evidence is now concrete enough that continued caution about regulating has flipped from prudent to negligent. Whether you trust the underlying capability claims or not, that is a genuine change in position from one of the field’s most influential voices, and it deserves to be read as such.

    The FAA analogy is doing enormous work, and it is worth poking at. Airplanes and drugs are mature technologies with stable physics and decades of incident data; the certification regime works because the failure modes are well understood. Frontier models are the opposite: the whole premise of the essay is that capabilities are changing faster than anyone can characterize them. Amodei half-acknowledges this when he warns that a fixed list of safety requirements tends to consume 95 percent of compliance effort on things that turn out not to matter while missing the real risks, a lesson he says Anthropic learned from its own Responsible Scaling Policy. So the proposal is really for an agency nimble enough to rewrite its own standards continuously, which is a much taller order than the FAA. The honest read is that he is proposing a regulator we do not yet know how to build, and betting that building it is still better than the alternative.

    The economics section is where Amodei is most careful, and it is the part most likely to be misread. He goes out of his way to say enduring job displacement is undesirable and that warning about it is not the same as wanting it, a distinction critics of AI leaders often collapse. His real claim is subtle: that AI might jam the economic policy dial on a “hypergrowth, hyper-inequality” setting that is hard to unstick, because AI substitutes for human cognition broadly and faster than past technologies, potentially overwhelming the usual escape hatches like comparative advantage and Jevons paradox. If he is right, the political fight of the next decade is not about growth, which AI supplies, but about distribution, which it does not. His mention of UBI, universal capital accounts, and higher capital gains taxes is notable coming from a frontier CEO, even hedged as it is.

    The civil liberties section is the one that should travel furthest beyond the AI-policy bubble, because it does not depend on accepting his most aggressive timelines. The data broker loophole, the idea that the government can simply buy the bulk data Americans hand to private companies and run mass analysis on it, is a problem that exists today; AI just raises the stakes by making that data vastly more revealing. Same with the proposal that anyone facing adverse government action should have access to AI at least as capable as what the government uses against them. These are concrete, near-term, and bipartisan in a way the abstract autonomy debates are not. The most candid line in the whole piece is his admission that AI cannot be safely entrusted to either governments or companies, an unusually direct acknowledgment that his own industry needs external checks, with Anthropic’s Long-Term Benefit Trust offered as one imperfect example rather than a solution.

    The geopolitics section is the most contested terrain. Framing AI as a nuclear-scale reset of the game board, with a virtual country of 100 million geniuses divisible across military strategy and weapons R&D, leads naturally to a democratic coalition that hoards chips and denies them to adversaries. That logic is internally consistent, but it sits in tension with the benefit-sharing and “eventually the whole world joins” language elsewhere in the same section. Export controls that lock down the supply chain are, by design, a tool of exclusion, and reconciling that with broad diffusion of AI’s benefits to developing countries is the circle the coalition idea has to square. Amodei is clearly aware of the tension and bets that making membership attractive resolves it. The closing image is the one to remember: Treebeard waking up, with the warning that the goal is to channel real public concern into constructive policy rather than let it curdle into formless anger.

    Key Takeaways

    • The core tension of the essay is a mismatch in speed: AI advances exponentially while legislation moves on a multi-year timescale, dramatized by the Treebeard and Hobbits image from The Lord of the Rings.
    • In only four years, AI models went from barely writing a coherent line of code to writing most of the code at major AI companies, with similar gains across biology, physics, math, finance, law, and translation.
    • Scaling laws now have over a decade of empirical support, and if they continue another year or two they likely produce “powerful AI,” a country of geniuses in a datacenter.
    • For the last few years, safety advocates including Anthropic focused on optionality-preserving policies: transparency legislation, chip export controls, and data collection on AI’s labor effects.
    • Amodei argues that posture is no longer enough. Claude Mythos Preview revealed that frontier models pose real cybersecurity risks to the financial sector, critical infrastructure, and national security, and proved AI is now a tool of strategic consequence.
    • He expects biological risks to follow cyber risks, with serious AI autonomy risks potentially not far behind.
    • The essay covers five policy areas: regulation and public safety, macroeconomics and tax policy, accelerating AI’s positive impact, the state and civil liberties, and securing leadership by democracies.
    • Alongside the essay, Anthropic released a legislative proposal on frontier model testing and a policy framework for job displacement, both with promised financial backing.
    • On regulation, Amodei invokes the Collingridge dilemma and Hayek’s information problem to explain why pre-writing AI law in 2023 to 2024 was risky, then argues the situation has now changed.
    • Anthropic’s 2025 answer was transparency, helping pass SB 53 in California, RAISE in New York, and SB 315 in Illinois, plus advocating a federal transparency standard.
    • He now calls for binding regulation modeled on the FAA, where frontier models must pass technical testing and can have release blocked or reversed if they fail high safety standards.
    • Models above a compute threshold should face mandatory third-party testing in four areas: cybersecurity, biological weapons, loss of control of AI systems, and automated R&D that accelerates the other three.
    • Government should be able to block or deter deployment of models judged to present unacceptable risk, scoped to those four risks with protections against political favoritism.
    • Evaluation could come from a government agency or from authorized and inspected private organizations under a “regulatory markets” approach.
    • AI companies should have strong security to protect model weights, conduct regular red teaming and penetration testing, report safety incidents promptly, and work with government against major threat actors.
    • He warns a time may come when the most powerful systems resemble weaponizable nuclear materials rather than airplanes, requiring more aggressive measures, but cautions against getting ahead of present dangers.
    • On economics, AI could deliver extremely rapid growth via accelerated science and operational efficiency, supercharged by AI building better AI.
    • The same properties make AI a broad substitute for human cognition that changes the economy faster than past technologies, risking large and potentially enduring labor market disruption.
    • The feared outcome is a “hypergrowth, hyper-inequality” setting that is hard to unstick, where the challenge shifts from incentivizing growth to sharing its benefits.
    • Amodei is emphatic that enduring job displacement is undesirable and dangerous, and that he warns about it to help society adapt, not as a prophet of doom.
    • Anthropic says it works with customers to find new revenue and use cases rather than only cost cutting, and explores interaction paradigms that keep humans active alongside AI.
    • He predicts AI will enable single individuals to build billion-dollar companies, noting teams of a few people already reach hundreds of millions in revenue, while admitting significant enduring job loss may be intrinsic to the technology.
    • Any response must address both economic provision and the human need for meaning, purpose, and agency, with the latter ultimately more important and beyond what policy can directly deliver.
    • Suggested economic interventions: better measurement and tracking (governments expanding statistics beyond Anthropic’s Economic Index), pro-employment incentives, and long-term macroeconomic support.
    • Pro-employment ideas include wage insurance, retention tax incentives, workforce training grants, and employer-employee matching infrastructure.
    • If displacement is large and permanent, mechanisms like universal basic income or universal capital accounts, financed through company taxes or higher capital gains taxes, may be necessary.
    • He frames datacenter and energy-price backlash as largely a symbol of broader economic anxiety, and says AI companies should pay to absorb rate increases, a pledge Anthropic has already made.
    • For technologies accelerated by AI, the bigger risk is regulators like the FDA being too slow, not too lax, because AI may make downstream tech safer in ways that violate skeptical regulatory assumptions.
    • Biomedicine is the illustrative case: AI could flood the drug pipeline, raise effect sizes, treat previously untreatable diseases, and create whole new therapy categories, while the current FDA and EMA pipeline takes 7 to 8 years.
    • Agencies should pre-approve standards for AI methods like PD/PK modeling, toxicology prediction, dose selection, biomarker validation, synthetic control arms, and surrogate endpoints, plus more flexible accelerated-approval mechanisms.
    • On civil liberties, powerful AI in the wrong hands could be the ultimate tool of autocracy, and existing constitutional protections are not fully equipped to counter a surprise seizure of power.
    • Threats named include fully automated drone armies that obey unlawful orders and surveillance AI that infers the innermost details of every citizen’s life from widely available data.
    • Civil liberties proposals: accountability rules and an “off switch” for autonomous weapons, a domestic ban on fully autonomous weapons including in law enforcement, closing the data broker loophole, and public rights to AI advice during adverse government action.
    • Amodei warns companies as well as governments can seize quasi-state power, citing the Gilded Age and the East India Company, and says AI cannot be safely entrusted to either alone.
    • He offers Anthropic’s Long-Term Benefit Trust as one separation-of-power structure and urges the industry to explore mechanisms that go further.
    • On geopolitics, he argues AI resets the geopolitical game board like nuclear weapons, becoming the dominant source of military and economic power for any nation that holds it.
    • A nation with powerful AI versus one without it, or even one three years behind, could resemble WWII Marines facing medieval swordsmen.
    • He calls for a democratic coalition that shares chips and semiconductor manufacturing equipment internally while denying them to adversaries, citing MATCH and OVERWATCH as good first steps.
    • The coalition should coordinate risk policy, share benefits including harmonized medical approvals, provide mutual AI defense, reject AI-powered repression, and cooperate on macroeconomic stabilization.
    • He rejects the idea that AI’s image is a PR problem, arguing public concern reflects real risks and is democratic accountability working as it should, with the task being to channel it into constructive solutions.

    Detailed Summary

    The speed mismatch between AI and policy

    Amodei frames the entire essay around a single problem: AI advances at a lightning pace while policy, especially legislation, moves very slowly, often for good reasons since governments wield grave powers that should not be used hastily. He illustrates this with Treebeard, the sentient tree from The Lord of the Rings who takes a full day to say hello, as a stand-in for political institutions trying to respond to a technology that can go from amusing toy to a country of geniuses in the time it takes Congress to act. He recounts the dilemma responsible actors have faced: they could see where the exponential was headed, but to observers looking only at present capabilities, AI looked as mundane as the latest consumer app or cryptocurrency, making a laissez-faire attitude hard to argue against. The absence of AI’s radical effects, and uncertainty about their shape, made it genuinely difficult to design good policy even where the will existed.

    That uncertainty, he says, is why safety advocates limited themselves to optionality-preserving measures like transparency rules, export controls, and labor data collection. But over the last few months the evidence of AI’s power and risk has become undeniable, with Claude Mythos Preview as the emblematic example: it scrambled the global cybersecurity landscape and proved AI models are now tools of global and national strategic consequence. He expects biological and autonomy risks to follow, and argues the world must now activate its slow, rickety policy apparatus to handle risks that will compound quickly. He worries current early actions are at least a year out of step with AI’s progress, and presents the essay as an attempt to close that gap across five policy areas, focused on US policy but relevant worldwide.

    Regulation and public safety: an FAA for frontier models

    Amodei opens by acknowledging the real costs of regulation: it can reduce a product’s benefits, disincentivize innovation, and suffer from the Hayekian problem that regulators lack the information for good tradeoffs, plus the Collingridge dilemma that a technology’s impacts are hard to anticipate until it is too late to manage them. In 2023 to 2024 these dynamics argued against pre-writing AI law, since the exact form of biological or autonomy risk, how to test for it, and how it would play out were all unclear, creating a high risk of low-value compliance requirements that miss the real dangers. Anthropic’s answer was transparency: requiring developers to disclose safety procedures, tests, and critical incidents, which is why it supported SB 53 in California, RAISE in New York, and SB 315 in Illinois in early 2026.

    Now, he argues, the risks are clearly here and it is time for binding regulation. His analogy is to cars, airplanes, and drugs: powerful technologies essential to the economy but capable of killing many people if designed or operated poorly. He models AI regulation on the FAA, with frontier models required to pass testing and auditing and with release blocked or reversed if they fail high safety standards. His concrete proposal: mandatory third-party testing for models above a compute threshold across cybersecurity, biological weapons, loss of control, and accelerating automated R&D; government power to block deployment of unacceptably risky models, scoped narrowly with anti-favoritism protections; evaluation by either a government agency or authorized private organizations in a regulatory-markets model; strong weight security, red teaming, and penetration testing at AI companies; and prompt reporting of safety incidents. He notes a future may arrive when systems resemble weaponizable nuclear materials and demand harsher measures, but warns against designing for dangers that have not yet emerged.

    Macroeconomics and tax policy: growth and displacement together

    Here Amodei challenges the standard premise that growth is fragile and must be traded off against the drag of taxes or deficits to reduce inequality. Powerful AI, he suggests, may scramble that assumption by producing extremely rapid growth through accelerated science and efficiency, supercharged by AI building better AI, while simultaneously acting as a broad substitute for human cognition that reshapes the economy faster than any prior technology. The result could be a world stuck on a hypergrowth, hyper-inequality setting that is hard to unstick, where the central challenge is no longer incentivizing growth but sharing its benefits. He is careful to make two points clearly: first, enduring job displacement is undesirable and dangerous and should be minimized, and his warnings are meant to help society adapt, not to play prophet of doom; second, any response must address both economic provision and the deeper human need for meaning, purpose, and agency, which matters more and which policy cannot directly supply.

    His policy menu starts with measurement and tracking, arguing good policy is impossible without accurate data, and that governments could expand economic statistics well beyond Anthropic’s Economic Index. Next come pro-employment incentives such as wage insurance, retention tax incentives, workforce training grants, and employer-employee matching, costs he says society should readily accept since they are likely offset by AI productivity gains. If displacement proves large and permanent, he says long-term income support like universal basic income or universal capital accounts may be needed, financed through taxes on relevant companies or higher capital gains taxes. He closes the section by reframing datacenter and energy-price backlash as mostly a symbol of broader economic anxiety, while saying AI companies should absorb rate increases, as Anthropic has pledged.

    Accelerating AI’s positive impact: the slow-regulator problem

    For technologies accelerated by AI, rather than AI itself, Amodei flips his concern: the bigger danger is regulatory systems designed for a slower pace failing to handle the deluge of new products, and AI making downstream technologies safer in ways that violate the skeptical assumptions baked into agencies like the FDA. He focuses on biomedicine as the area likely to produce AI’s biggest humanitarian benefits and where regulation is especially complex. AI could greatly increase the rate of new drug candidates, improve their effect sizes and safety profiles, treat previously untreatable diseases, and create entirely new therapy categories the way antibodies, peptides, and cell therapies did.

    The current pipeline at the FDA and EMA takes 7 to 8 years, built on the pessimistic assumption that drug candidates usually fail and often carry safety problems even when they work. Without reform, AI will jam or overload that system. Amodei proposes that agencies develop standards now for accepting AI simulation and analysis, so they can be adopted quickly once proven rather than after years of unnecessary testing. Specific candidates include AI-based PD/PK modeling, toxicology prediction to reduce animal testing, more accurate dose selection, biomarker validation from large datasets, synthetic control arms, and surrogate endpoints (especially for aging and neurodegeneration). He urges more flexible accelerated-approval mechanisms generally, and notes biomedical acceleration may also reduce AI’s risks by aiding biodefense and improving mental health.

    The state and civil liberties: guarding against AI-driven tyranny

    Amodei frames the perennial balance between state power and individual liberty, enforced through machinery like the First, Fourth, and Fifth Amendments, the Posse Comitatus Act, and FISA, and argues AI threatens to upset that balance while raising its stakes. Powerful AI in the wrong hands could be the ultimate tool of autocracy, because the enormous returns to intelligence combined with AI’s pace create a perfect storm for a surprise seizure of power. The danger could take many forms but shares one feature: AI conferring sudden power while routing around democratic oversight. He cites a fully automated drone army that could obey unlawful orders, where trained humans might object, and a surveillance AI that analyzes widely available information at massive scale to infer the innermost details of every citizen’s life, an ability current civil liberties law never contemplated.

    His proposals: create accountability rules for autonomous weapons so they respond to court orders, legislation, and human overseers rather than blindly following orders, possibly with a judicial finger on an off switch; ban domestic use of fully autonomous weapons, including in law enforcement, while allowing them against foreign adversaries; close the bulk-collection and data-broker loophole that lets the government buy and analyze data Americans share with private companies; and guarantee public rights to AI advice at least as capable as what the government uses during adverse action, as an extension of the Administrative Procedure Act, due process, or the Sixth Amendment. He closes by warning that companies, not just governments, can capture the state, citing the Gilded Age and East India Company, and argues AI cannot be safely entrusted to either alone. Anthropic’s Long-Term Benefit Trust is offered as one accountability structure, with a call for the industry to go further.

    Securing leadership by democracies: a values-based coalition

    Amodei rejects treating AI as a mere instrument of trade policy to diffuse a tech stack worldwide. He believes AI resets the entire geopolitical game board like nuclear weapons, potentially even more so, becoming the dominant source of military and economic power for whoever holds it. In a virtual country of 100 million geniuses, millions could be assigned to military strategy, drone manufacture, weapons R&D, intelligence, and scientific advancement at once, so a nation with powerful AI facing one without it, or even three years behind, could be like WWII Marines against medieval swordsmen. Because powerful AI also enables deeper autocratic repression, it matters enormously that the world’s strongest nations are democracies.

    His answer is a global coalition built on shared democratic values that draws in the rest of the world by making membership increasingly attractive and exclusion increasingly costly. Operating principles include managing the AI supply chain by sharing chips and semiconductor manufacturing equipment within the coalition while denying them to adversaries, expanding and tightening export controls (he cites MATCH and OVERWATCH as good first steps); coordinating on biological, cyber, and autonomy risk to make compliance compatible and effective; sharing AI’s benefits including harmonized medical approvals; mutual defense through collective AI cyberdefense, drones, manufacturing, compute, and intelligence; rejection of AI-powered repression; and macroeconomic cooperation against contagious employment crises. The coalition would respect each nation’s sovereignty, start with aligned democracies, and grow iteratively, ideally toward the whole world, but at minimum positioning democracies to contain and outcompete repressive regimes.

    A window of opportunity

    Amodei closes on cautious optimism. The same exponential that strains policymaking has created a unique opening: clear evidence of AI’s risks, an early taste of its value and disruption, and public backlash against unregulated approaches have left policymakers unusually open to forward-looking action. Treebeard and his forest are waking up. He firmly rejects the industry-circle view that this is a PR problem solved by better marketing, arguing people are worried because the risks are real, and that public concern in response to transparency is democratic accountability working as it should. The key challenge is focusing that concern into constructive solutions rather than letting it descend into formless anger and violence. He is optimistic because issues from job displacement to model testing to export controls have common-sense appeal across the political spectrum, and a broad nonpartisan coalition could adopt sane, forward-looking policy faster than usual.

    Notable Quotes

    “in only four years, AI models have gone from barely being able to write a coherent line of code to writing most of the code at major AI companies.”

    Dario Amodei, on the pace of the AI exponential

    “in the several years that it can take Congress to act, AI can go from an amusing toy to the full country of geniuses.”

    Dario Amodei, on the mismatch between AI’s speed and the speed of legislation

    “However, now the risks are clearly here. It is time to go beyond transparency to more serious and binding regulation of AI.”

    Dario Amodei, marking the shift from transparency to binding rules

    “enduring job displacement is undesirable and dangerous, and we should do everything we can to minimize or prevent it, not to bring it about.”

    Dario Amodei, clarifying his stance on AI and jobs

    “The key challenge in such a world won’t be incentivizing growth, but finding a way for everyone to share in the benefits.”

    Dario Amodei, on a hypergrowth, hyper-inequality economy

    “Powerful AI in the wrong hands could be the ultimate tool of autocracy, and our existing legal and constitutional protections are not fully equipped to counter this threat.”

    Dario Amodei, on AI and civil liberties

    “A nation that possesses powerful AI facing one without it … could be the equivalent of an army of World War II Marines facing an army of medieval swordsmen.”

    Dario Amodei, on AI as the dominant source of geopolitical power

    “People are worried about AI because they correctly perceive that its risks are real, not because AI CEOs have been insufficiently Panglossian.”

    Dario Amodei, rejecting the idea that AI has a PR problem

    “Treebeard and his forest are waking up.”

    Dario Amodei, on policymakers’ new openness to acting on AI

    “Policy on the AI Exponential” is a dense, structured argument from one of the most consequential figures in the field, and it rewards a full read in the original. The summary and analysis above are a guide, not a substitute. You can read the full essay here.

    Related Reading

  • Claude Fable 5 and Claude Mythos 5: Anthropic Ships Its First Generally Available Mythos-Class AI Model With New Safeguards

    Anthropic has launched Claude Fable 5 and Claude Mythos 5, the first Mythos-class models offered beyond a tiny circle of cyber defenders. Fable 5 is the generally available version, wrapped in a new layer of safeguards, while Mythos 5 is the same underlying model with some of those guardrails lifted for a small group of vetted partners. The pair sits a full tier above the Opus class in raw capability, and the launch is as much a story about how Anthropic is choosing to gate that capability as it is about the benchmarks. Below is a full breakdown of what shipped, what the model can do, and why the safeguard design matters.

    TLDR

    Anthropic released Claude Fable 5, a Mythos-class model that is now its most capable generally available model, posting state-of-the-art results across software engineering, knowledge work, vision, memory, and scientific research. To ship it safely and fast, Fable 5 carries new safety classifiers that route flagged queries in cybersecurity, biology and chemistry, and distillation over to Claude Opus 4.8 instead of refusing, a fallback that triggers in under 5% of sessions. The same model ships without cyber safeguards as Claude Mythos 5 for Project Glasswing partners in collaboration with the US Government, where it is described as having the strongest cybersecurity capabilities of any model in the world. Highlights include a codebase-wide migration of a 50-million-line Ruby codebase that Stripe says took a day instead of two months, beating Pokemon FireRed with a vision-only harness, accelerating drug design roughly tenfold using Mythos 5, producing novel molecular biology hypotheses preferred by scientists about 80% of the time, and over a week of autonomous genomics research. Both models cost 10 dollars per million input tokens and 50 dollars per million output tokens, less than half the price of Mythos Preview, with a staged subscription rollout and a new 30-day data retention policy for Mythos-class traffic.

    Thoughts

    The most interesting decision here is not the capability jump, it is the naming split. Fable and Mythos are the same brain. The only difference is whether the safeguards are on. Anthropic is effectively shipping one model twice: a gated public edition and an ungated edition handed to a short list of trusted defenders working with the US Government. That is a clean way to resolve the central tension of frontier AI, which is that the exact capabilities that help a security professional close a vulnerability also help an attacker find one. Rather than dumbing the model down for everyone or holding it back entirely, they are letting the access list, not the weights, carry the risk. Expect this pattern to repeat as capabilities climb.

    The fallback-to-Opus design is the other quietly important choice. When a classifier flags a query in cybersecurity, biology, chemistry, or suspected distillation, the user does not hit a wall of refusal. The request is silently handed to Opus 4.8, a model that is still excellent at almost everything. Graceful degradation beats a hard no, both for user experience and for trust. It also reframes what a safeguard is. Instead of a binary block, it becomes a routing decision, and because more than 95% of sessions never trigger it, most users will never notice it exists. The honest admission that the classifiers are tuned conservatively and will sometimes catch harmless requests is the right posture, even if it will annoy power users who keep getting bounced to the smaller model.

    The commercial signals are worth reading closely. Pricing came down to less than half of Mythos Preview, which suggests confidence in serving costs at scale, but the subscription rollout tells a more cautious story. Fable 5 is free on Pro, Max, Team, and Enterprise plans only through June 22, after which using it requires usage credits until capacity catches up. That is a polite way of saying demand is expected to badly outrun supply. The model is fully available on the API and consumption-based Enterprise plans from day one, because those bill by the token and self-throttle. Subscriptions, which are all-you-can-eat, are where a capacity crunch actually hurts, so that is exactly where the brakes went on.

    On the science, the genomics result is the one that should make people sit up. A model doing over a week of largely autonomous research, assembling single-cell data across 138 species, then designing and training its own machine learning model that outperforms a recently published Science paper while being 100 times smaller, is a different category of claim than acing a benchmark. So is the drug-design work, where Mythos 5 reportedly matches or beats skilled human operators end to end, choosing binding sites, running protein design tools, and recovering from its own failures. If those hold up to publication and independent replication, the interesting frontier stops being chat quality and becomes whether a model can run a research program. That is also precisely why the biology and chemistry classifier exists, and why Anthropic is being so deliberate about who gets the ungated version.

    One caveat worth keeping in view: nearly all of the evidence in the announcement is Anthropic’s own, or comes from partners with early access and an incentive to be enthusiastic. The Stripe migration, the FrontierCode score, the Slay the Spire memory result, the protein targets, and the genomics model are all compelling, but they are first-party until outside labs and the eventual system card, peer review, and independent red-teamers weigh in. The note that the UK AISI made progress toward a universal jailbreak inside a brief testing window is a useful reminder that the safeguard story is a work in progress, not a finished proof.

    Key Takeaways

    • Claude Fable 5 is a Mythos-class model made safe for general use, and is now Anthropic’s most capable generally available model.
    • Mythos-class is a tier that sits above the Opus class in capability. The first was Claude Mythos Preview, released in April through Project Glasswing.
    • Fable 5 is state-of-the-art on nearly all tested benchmarks, and its lead grows as tasks get longer and more complex.
    • Claude Mythos 5 is the same underlying model as Fable 5, but with safeguards lifted in some areas. Fable and Mythos differ only by their safeguards.
    • Mythos 5 is described as having the strongest cybersecurity capabilities of any model in the world, and is deployed through Project Glasswing with the US Government.
    • New safety classifiers cover cybersecurity, biology and chemistry, and distillation. Flagged queries fall back to Claude Opus 4.8 rather than being refused.
    • Users are told whenever a fallback happens. More than 95% of Fable sessions involve no fallback at all, and for those sessions Fable performs effectively the same as Mythos 5.
    • The safeguards are tuned conservatively and trigger in less than 5% of sessions on average, sometimes catching harmless requests. Anthropic plans to reduce false positives after launch.
    • Stripe reported Fable 5 compressed months of engineering into days, performing a codebase-wide migration of a 50-million-line Ruby codebase in a day that would have taken a team over two months by hand.
    • Fable 5 scores highest among frontier models on Cognition’s FrontierCode evaluation for high-quality agentic coding, even at medium effort, and is more token-efficient than past Claude models.
    • On Hebbia’s Finance Benchmark for senior-level reasoning, Fable 5 has the highest score of any model, with gains in document reasoning, chart and table interpretation, and problem solving.
    • IMC noted Fable 5 aced their trading-analysis evaluations nearly across the board, including factual lookup, conceptual reasoning, root-cause analysis, and expected-value analysis.
    • Fable 5 is the new state-of-the-art for vision, and can rebuild a web app’s source code from screenshots alone.
    • Fable 5 beat Pokemon FireRed using a minimal, vision-only harness with no maps, navigation aids, or extra game-state information. Earlier Claude models needed a complex helper harness.
    • Persistent file-based memory improved Fable 5’s Slay the Spire performance three times more than it did for Opus 4.8, and Fable reached the game’s final act three times more often.
    • Fable 5 built a simulation of the solar system, deriving the planets’ orbital motion from physics first principles and using it to predict solar eclipses.
    • Using Mythos 5, internal protein design experts accelerated aspects of drug design by around ten times, with the model matching or beating skilled human operators end to end.
    • Nine of 14 protein targets in the drug-design study yielded strong candidates Anthropic is now investigating.
    • Mythos 5 is Anthropic’s first model to consistently produce novel, compelling scientific hypotheses. Scientists preferred its molecular biology hypotheses about 80% of the time in blinded comparisons.
    • One Mythos hypothesis, a novel mechanism for an E. coli protein, was corroborated by an independent lab working on the same problem.
    • In over a week of largely autonomous work, Mythos 5 assembled single-cell data for millions of cells across 138 animal species and trained a custom model that outperformed a recent Science paper while being 100 times smaller.
    • Anthropic’s automated alignment assessment found Mythos 5’s level of misaligned behavior was low and similar to Opus 4.8. Because they are the same model, Fable 5’s alignment is similar.
    • An external bug bounty produced no universal jailbreaks in over 1,000 hours of testing, though the UK AISI made progress toward one in a brief initial window.
    • One external partner found Fable 5’s safeguards against harmful cyber queries the most robust of any model tested, including Opus 4.8 and Opus 4.7, with zero compliance on harmful single-turn cyberattack requests.
    • The biology and chemistry classifier is deliberately broad for now. Mythos-class models outperformed dedicated protein language models at predicting AAV viral shell assembly using biological reasoning alone.
    • The distillation classifier targets large-scale attempts to extract Claude’s capabilities to train competing models, which could proliferate near-frontier capabilities without safeguards.
    • A new policy requires 30-day data retention for all Mythos-class traffic on first- and third-party surfaces, used only for safety, with logged human access and deletion after 30 days in almost all cases.
    • Anthropic plans trusted access programs that let cybersecurity organizations apply for Mythos 5, and let a small number of life science researchers access Fable 5 with biology and chemistry safeguards removed.
    • Both models cost 10 dollars per million input tokens and 50 dollars per million output tokens, less than half the price of Mythos Preview. Developers can use claude-fable-5 via the Claude API.
    • Fable 5 is free on Pro, Max, Team, and seat-based Enterprise plans through June 22. On June 23 it moves to usage credits on those plans until capacity allows it to return as a standard inclusion.

    Detailed Summary

    A Mythos-class model, made safe for general use

    Fable 5 is the first Mythos-class model Anthropic has made generally available. Mythos-class is a tier that sits above the Opus class, and the first of its kind, Claude Mythos Preview, was released in April through Project Glasswing to a limited group of cyber defenders and critical software infrastructure providers. The company framed today’s launch as the moment it could finally bring that level of capability to all users, because its safeguards had matured enough to allow it. Fable 5’s capabilities exceed those of any model Anthropic has made generally available, and its advantage over other models grows as tasks get longer and more complex.

    Two models, one brain

    Claude Mythos 5 is the same underlying model as Fable 5, but with safeguards lifted in some areas. The names are the only real difference: Fable, from the Latin fabula meaning that which is told, is akin to the Greek mythos, and the safeguards are what distinguish the two. Mythos 5 launches first to existing Mythos Preview users, including the Project Glasswing cybersecurity partners, as an upgrade. It is deployed in collaboration with the US Government and is described as having the strongest cybersecurity capabilities of any model in the world. Anthropic plans to steadily expand access through a more systematic trusted access program.

    Software engineering and token efficiency

    Fable 5 can work autonomously for longer than any previous Claude model, and software engineering is where that shows most clearly. During early testing, Stripe reported it compressed months of engineering into days, performing a codebase-wide migration in a 50-million-line Ruby codebase in a single day that would otherwise have taken a whole team over two months by hand. It is also more token-efficient than past models, scoring highest among frontier models on Cognition’s FrontierCode evaluation for high-quality, maintainable agentic coding, even at medium effort.

    Knowledge work, vision, and memory

    On complex analytical work, Fable 5 posted the highest score of any model on Hebbia’s Finance Benchmark for senior-level reasoning, with substantial gains in document-based reasoning and chart and table interpretation, and IMC said it aced their trading-analysis evaluations nearly across the board. In vision, it is the new state-of-the-art, able to extract precise numbers from detailed scientific figures and rebuild a web app’s source code from screenshots alone. It needs less scaffolding too: where earlier Claude models struggled to play Pokemon even with helper harnesses, Fable 5 beat FireRed with a minimal, vision-only harness using nothing but raw game screenshots. On memory, giving Fable persistent file-based notes improved its Slay the Spire performance three times more than it did for Opus 4.8, and it built a physics-first-principles solar system simulation accurate enough to predict solar eclipses.

    Life sciences: drug design, hypotheses, and genomics

    Using Mythos 5, Anthropic’s internal protein design experts accelerated aspects of the drug-design process by around ten times. With protein design and bioinformatics tools but no human assistance, the model matched or beat skilled human operators, executing the full workflow of choosing binding sites, selecting and running design tools, and recovering from failures. Nine of 14 protein targets yielded strong drug-design candidates now under investigation. Mythos 5 is also Anthropic’s first model to consistently produce novel, compelling scientific hypotheses: scientists preferred its molecular biology hypotheses about 80% of the time in blinded comparisons, and one, a novel mechanism for an E. coli protein, was corroborated by an independent lab. In genomics, Mythos 5 ran over a week of largely autonomous research, assembling single-cell data for millions of cells across 138 species and training a custom model that outperformed a recent Science paper despite being 100 times smaller.

    The new safeguards: classifiers and fallback

    Mythos-class capability is potent enough that Anthropic considers it a substantial misuse risk, especially given how much advanced AI usage is dual use. Fable 5 ships with a new set of classifiers, separate AI systems that detect potential misuse and jailbreak attempts and stop the main model from responding. When a classifier flags a request related to cybersecurity, biology and chemistry, or distillation, the response is handled by Claude Opus 4.8 instead, and the user is told. The cybersecurity classifiers cover both exploitation and broader offensive cyber tasks like reconnaissance and lateral movement, and Anthropic says they prevent Fable from making any progress on those tasks. The biology and chemistry classifier is intentionally broad for now, after tests showed Mythos-class models could outperform dedicated protein language models at predicting AAV viral shell assembly using biological reasoning alone. The distillation classifier targets large-scale attempts to extract Claude’s capabilities to train competing models.

    Jailbreak resistance, data retention, and availability

    Anthropic ran extensive red-teaming, including an external bug bounty that produced no universal jailbreaks in over 1,000 hours, though it notes the UK AISI made progress toward one in a brief window. The company concedes it is likely impossible to fully prevent universal jailbreaks and aims instead to make any that remain slow and costly enough to catch before they scale. A new policy requires 30-day data retention for all Mythos-class traffic, used only for safety, with logged human access and deletion after 30 days in almost all cases. On availability, Fable 5 is live everywhere today and fully available on the API and consumption-based Enterprise plans, while subscription access rolls out in stages: free on Pro, Max, Team, and seat-based Enterprise through June 22, then on usage credits from June 23 until capacity allows it to return as a standard inclusion. Both models cost 10 dollars per million input tokens and 50 dollars per million output tokens.

    Notable Quotes

    “Today we’re launching Claude Fable 5: a Mythos-class model that we’ve made safe for general use.”

    Anthropic, opening the Claude Fable 5 and Claude Mythos 5 announcement

    “Fable 5’s capabilities exceed those of any model we’ve ever made generally available.”

    Anthropic, on where Fable 5 sits in the lineup

    “It has the strongest cybersecurity capabilities of any model in the world.”

    Anthropic, describing Claude Mythos 5

    “During early testing, Stripe reported that Fable 5 compressed months of engineering into days.”

    Anthropic, on Fable 5’s software engineering results

    “Our early data shows that more than 95% of Fable sessions involve no fallback at all.”

    Anthropic, on how often the safeguards route to Opus 4.8

    “Mythos 5 is our first model to consistently produce novel, compelling scientific hypotheses.”

    Anthropic, on the model’s molecular biology research

    “It is likely impossible to completely prevent universal jailbreaks, but our goal is to make any remaining jailbreaks sufficiently slow and costly that we can detect and prevent them before they are used at scale.”

    Anthropic, on the limits of its safeguards

    “Fable is from the Latin fabula, ‘that which is told,’ akin to the Greek mythos. The safeguards are what distinguish the two models.”

    Anthropic, explaining the Fable and Mythos naming

    Read the full announcement and the benchmark tables on Anthropic’s site here: Claude Fable 5 and Claude Mythos 5.

    Related Reading

  • Claude Opus 4.8 Released: Anthropic Bets on Honesty, Dynamic Workflows, Effort Control, and Cheaper Fast Mode

    Anthropic has released Claude Opus 4.8, the newest member of its flagship Opus class, available today across every surface and priced exactly like the model it replaces. The company calls it “a modest but tangible improvement” on Opus 4.7, but the framing undersells what is actually interesting here: the headline upgrade is not a benchmark number, it is honesty. Opus 4.8 is built to know when it does not know, and that single behavioral shift may matter more for real agent work than any raw capability bump.

    TLDR

    Claude Opus 4.8 is an across-the-board upgrade to Anthropic’s Opus class that ships today at the same regular price as Opus 4.7 ($5 per million input tokens, $25 per million output tokens), with the model positioned as “a more effective collaborator.” The marquee improvement is honesty: Opus 4.8 is roughly four times less likely than its predecessor to let flaws in its own code pass unremarked, and it is more willing to flag uncertainty rather than confidently claim progress on thin evidence. A pre-release alignment assessment found new highs on prosocial traits like supporting user autonomy and acting in the user’s best interest, with misaligned behavior at rates similar to Anthropic’s best-aligned model, Claude Mythos Preview. Three things launch alongside the model: dynamic workflows in Claude Code (research preview), where Claude plans work then runs hundreds of parallel subagents that run even longer and verify their own outputs before reporting back; effort control in claude.ai and Cowork, a slider for how hard Claude thinks; and a Messages API update that accepts system entries inside the messages array so developers can update instructions mid-task without breaking the prompt cache. Fast mode now runs at 2.5x speed and is three times cheaper than before ($10 / $50 per million tokens). The roadmap points to cheaper Opus-equivalent models, a higher-intelligence class above Opus, and a wider rollout of Mythos-class models gated behind stronger cyber safeguards under Project Glasswing.

    Thoughts

    The most important sentence in this announcement is not about coding scores. It is the claim that Opus 4.8 is about four times less likely than Opus 4.7 to let flaws in its own code slip by without comment. For a chat assistant, overconfidence is annoying. For an agent, it is catastrophic. The whole premise of long-running autonomous work is that you hand the model a task and walk away, which means the model’s own judgment about whether it succeeded becomes the only judgment in the loop until you come back. A model that confidently declares victory on a half-finished migration does not save you time, it costs you a debugging session plus the time you spent trusting it. Honesty, framed this way, is not a soft virtue. It is the load-bearing reliability property that makes unattended agents usable at all.

    Read the launch as a single coherent argument rather than a list of features, and the pieces lock together. Dynamic workflows let Claude plan a job and fan out hundreds of parallel subagents that, with Opus 4.8, run longer than before. Effort control lets you dial up how much the model thinks. The honesty improvement means the model checks its own work and flags what it is unsure about instead of papering over it. Put those three together and you get one product thesis: let it run longer, let it think harder, and trust it to tell you when something is wrong. The codebase-scale migration example, hundreds of thousands of lines from kickoff to merge with the existing test suite as the bar, is the proof point. None of those three capabilities is worth much alone. A model that runs for hours but lies about its results is a liability. A model that flags uncertainty but cannot sustain a long task never reaches the moment where its honesty matters. Anthropic shipped all three at once because they only pay off together.

    The economics deserve a closer look than the “same price” headline invites. Regular pricing is flat versus Opus 4.7, which is the polite way of saying you get a better model for free. The real move is fast mode: 2.5x the speed at three times cheaper than it cost on previous models, landing at $10 per million input and $50 per million output. That is Anthropic quietly attacking the latency-versus-cost tradeoff that has shaped how teams deploy frontier models. Until now, “fast” meant “expensive,” so you reserved it for interactive moments and ate the wait everywhere else. Collapsing that premium changes the default. And note the subtle token story underneath: Opus 4.8 at its default high effort spends roughly the same tokens on coding as Opus 4.7’s default while performing better, so the effort slider is not a way to bleed you dry, it is an honest exposure of the quality-cost dial that was always there implicitly.

    The Messages API change is the kind of unglamorous plumbing that practitioners will appreciate immediately. Letting system entries live inside the messages array means you can update an agent’s instructions, permissions, token budget, or environment context partway through a task without smuggling the update through a fake user turn and without blowing up your prompt cache. Anyone who has built a long-running agent has hit this wall: the world changes mid-task, the agent needs new constraints, and the only clean way to inject them previously was a cache-busting hack. This is Anthropic treating agents as first-class, stateful, long-lived processes rather than oversized chat sessions. It is a small spec change with outsized implications for how you architect an agent that runs for an hour.

    Then there is the roadmap, where the most telling line is the quietest. Anthropic says a small number of organizations are already using Claude Mythos Preview for cybersecurity work under Project Glasswing, and that models of this capability level require stronger cyber safeguards before general release. Notice that they are pinning Opus 4.8’s alignment numbers to Mythos as the benchmark for “best-aligned,” while simultaneously holding Mythos back from general availability on safety grounds. That is a deliberate signal: the next class of model is good enough that they are gating it on cyber-offense risk, not on capability. For a site about the pursuit of joy, fulfillment, and purpose through AI, this is the part worth sitting with. The frontier is increasingly defined not by what the models can do, but by what their builders decide it is responsible to ship. Honesty in the small (flagging a bad line of code) and restraint in the large (holding back a cyber-capable model) are the same instinct expressed at two different scales.

    Key Takeaways

    • Claude Opus 4.8 is now available everywhere, replacing Opus 4.7 as Anthropic’s flagship Opus-class model and positioned as “a more effective collaborator.”
    • Regular usage pricing is unchanged from Opus 4.7, holding at $5 per million input tokens and $25 per million output tokens, so the capability gains come at no added cost.
    • The single most emphasized improvement is honesty, which Anthropic treats as a core trained behavior rather than a marketing flourish.
    • Evaluations show Opus 4.8 is around four times less likely than its predecessor to let flaws in its own code pass unremarked, a direct reliability win for autonomous coding.
    • Early testers report the model is more likely to flag uncertainty about its work and less likely to make unsupported claims or jump to conclusions on thin evidence.
    • A detailed alignment assessment was run before release and concluded Opus 4.8 reaches new highs on prosocial traits like supporting user autonomy and acting in the user’s best interest.
    • Misaligned behavior such as deception or cooperation with misuse is at rates substantially lower than Opus 4.7 and similar to Anthropic’s best-aligned model, Claude Mythos Preview.
    • The full alignment assessment and pre-deployment safety tests are documented in the public Claude Opus 4.8 System Card.
    • Dynamic workflows launch as a research preview inside Claude Code, letting Claude plan the work and then run hundreds of parallel subagents in a single session.
    • With Opus 4.8, those subagents can run even longer, and Claude verifies its outputs before reporting back rather than declaring success blindly.
    • Anthropic’s flagship example for dynamic workflows is a codebase-scale migration across hundreds of thousands of lines of code, from kickoff to merge, using the existing test suite as the success bar.
    • Dynamic workflows are available in Claude Code for the Enterprise, Team, and Max plans.
    • Effort control arrives in claude.ai and Cowork as a setting next to the model selector that lets users choose how much effort Claude puts into a response.
    • Higher effort makes Claude think more frequently and deeply for better answers; lower effort responds faster and consumes rate limits more slowly. Effort control is available on all plans.
    • Opus 4.8 defaults to “high” effort, judged the best overall balance of quality and user experience.
    • On coding tasks, the default effort spends a similar number of tokens as Opus 4.7’s default but delivers better performance, so quality rises without a token penalty.
    • Users can select “extra” (called “xhigh” in Claude Code) or “max” to spend more tokens for stronger results, and Anthropic recommends “extra” for difficult tasks and long-running asynchronous workflows.
    • Rate limits in Claude Code were increased to accommodate the higher token usage of the higher effort levels.
    • The Messages API now accepts system entries inside the messages array, a meaningful change for agent developers.
    • That update lets developers change Claude’s instructions mid-task, adjusting permissions, token budgets, or environment context, without breaking the prompt cache or routing through a user turn.
    • Fast mode now runs at 2.5x speed and is three times cheaper than it was for previous models, priced at $10 per million input tokens and $50 per million output tokens.
    • Developers access the model as claude-opus-4-8 through the Claude API.
    • Partner Miguel Gonzalez reports Opus 4.8 scored 84% on Online-Mind2Web, a meaningful jump over both Opus 4.7 and GPT-5.5, calling it the strongest computer-use and browser-agent model his team has tested.
    • Databricks reports that, inside Genie, Opus 4.8 reasons over unstructured content like PDFs and diagrams at 61% cheaper token cost than Opus 4.7.
    • Thomson Reuters reports Opus 4.8 is the first model to break 10% overall on the all-pass standard of its Legal Agent Benchmark, the highest score recorded there.
    • Eleven partners weighed in, including Cursor, Cognition’s Devin, Databricks Genie, Thomson Reuters CoCounsel, and Hebbia, spanning coding, legal, finance, and enterprise data work.
    • Anthropic is working on models that deliver many of the same capabilities as Opus at a lower cost.
    • The company plans to release a new class of model with even higher intelligence than Opus.
    • Under Project Glasswing, a small number of organizations are already using Claude Mythos Preview for cybersecurity work, with Mythos-class models expected to reach all customers in the coming weeks once stronger cyber safeguards are in place.

    Detailed Summary

    What Claude Opus 4.8 Is

    Claude Opus 4.8 is an upgrade to Anthropic’s Opus class of models, building on Opus 4.7 with improvements across benchmarks covering coding, agentic skills, reasoning, and practical knowledge-work tasks. Anthropic describes the result as “a more effective collaborator” while characterizing the release overall as “a modest but tangible improvement on its predecessor.” The model is available today, everywhere, and developers call it as claude-opus-4-8 via the Claude API. The announcement includes a comparison table against the predecessor and other models, though the per-cell numbers in that table are published as an image and are not reproduced here as text.

    Honesty: The Headline Improvement

    Anthropic singles out honesty as one of the most prominent improvements in Opus 4.8. All of the company’s models are trained to be honest, which includes avoiding claims they cannot support. A persistent problem with AI models generally is that they sometimes jump to conclusions, confidently claiming progress despite thin evidence. Early testers report that Opus 4.8 is more likely to flag uncertainties about its own work and less likely to make unsupported claims. The most concrete measure: evaluations show Opus 4.8 is around four times less likely than its predecessor to allow flaws in code it has written to pass unremarked. For agentic and unattended use, this self-skepticism is the difference between a model that reliably tells you when something went wrong and one that quietly ships a broken result.

    Alignment Assessment

    A detailed alignment assessment was run before release. On the positive side, the Alignment team concluded that Opus 4.8 “reaches new highs on our measures of prosocial traits like supporting user autonomy and acting in the user’s best interest.” On the risk side, misaligned behavior such as deception or cooperation with misuse occurs at rates substantially lower than Opus 4.7, and similar to Anthropic’s best-aligned model, Claude Mythos Preview. The full alignment assessment and the pre-deployment safety tests are published in the Claude Opus 4.8 System Card, which also contains the complete benchmark table and wider evaluations.

    Dynamic Workflows in Claude Code

    Launching today as a research preview in Claude Code, dynamic workflows let Claude plan the work and then run hundreds of parallel subagents in a single session. With Opus 4.8, those agents can run even longer than before, and Claude verifies its outputs before reporting back rather than reporting unchecked results. The showcase example is a codebase-scale migration: Claude Code with Opus 4.8 can carry out migrations across hundreds of thousands of lines of code, all the way from kickoff to merge, using the existing test suite as its bar for success. Dynamic workflows are available in Claude Code for the Enterprise, Team, and Max plans.

    Effort Control

    Effort control arrives in claude.ai and Cowork as a setting alongside the model selector that lets users choose how much effort Claude puts into a response. Higher effort means Claude thinks more frequently and deeply for better responses; lower effort means it responds faster and uses rate limits more slowly. Opus 4.8 defaults to “high” effort, which Anthropic judged the best overall balance of quality and user experience. On coding tasks, that default spends a similar number of tokens as Opus 4.7’s default while performing better. Users who want more can choose “extra” (called “xhigh” in Claude Code) or “max” to spend more tokens for stronger results, and Anthropic recommends “extra” for difficult tasks and long-running asynchronous workflows. To support the heavier token usage at higher effort levels, rate limits in Claude Code were increased. Effort control is available on all plans.

    Messages API Update

    The Messages API now accepts system entries inside the messages array. This lets developers update Claude’s instructions mid-task without breaking the prompt cache and without routing the update through a user turn. In practice that means you can update permissions, token budgets, or environment context while an agent is running, which is exactly the kind of statefulness a long-running autonomous process needs. It is a small specification change with significant consequences for how developers build durable agents.

    Pricing and Fast Mode

    Regular usage pricing is unchanged from Opus 4.7: $5 per million input tokens and $25 per million output tokens. The notable shift is in fast mode, where the model works at 2.5x the speed and fast mode is now three times cheaper than it was for previous models, landing at $10 per million input tokens and $50 per million output tokens. The combination of unchanged regular pricing and dramatically cheaper fast mode reshapes the latency-versus-cost calculus that has long governed how teams deploy frontier models.

    Partner Results Across Coding, Legal, Finance, and Data

    Eleven partners shared results spanning the spectrum of professional work. Miguel Gonzalez reports 84% on Online-Mind2Web, a meaningful jump over both Opus 4.7 and GPT-5.5, calling it the strongest computer-use and browser-agent model his team has tested. Databricks reports that Genie reasons over unstructured content like PDFs and diagrams at 61% cheaper token cost than Opus 4.7. Thomson Reuters reports Opus 4.8 is the first model to break 10% overall on the all-pass standard of its Legal Agent Benchmark. Cursor reports gains across every effort level on CursorBench with more efficient tool calling, and Cognition reports that Devin sees cleaner tool use, fixes to the comment-verbosity and tool-calling issues seen with Opus 4.7, and improvements over Opus 4.6. Hebbia reports strong quality with better citation precision and more token efficiency on retrieval for dense financial filings. The footnotes note that Terminal-Bench 2.1 was scored on the Terminus-2 public harness (GPT-5.5’s Codex CLI harness score is 83.4%), that OSWorld-Verified methodology changed with Opus 4.7’s score updated to 82.3%, and that on Finance Agent v2 Gemini 3.5 Flash scores 57.9%.

    What Is Next: Cheaper Models, Higher Intelligence, and Mythos

    Anthropic outlined a three-part roadmap. First, the company is working on models that provide many of the same capabilities as Opus at a lower cost. Second, it plans to release a new class of model with even higher intelligence than Opus. Third, as part of Project Glasswing, a small number of organizations are currently using Claude Mythos Preview for cybersecurity work; models of this capability level require stronger cyber safeguards before general release, and Anthropic expects to bring Mythos-class models to all customers in the coming weeks.

    Notable Quotes

    “Claude Opus 4.8 has noticeably better judgment. In Claude Code, it asks the right questions, catches its own mistakes, pushes back when a plan isn’t sound, and builds up confidence around complex, multi-service explorations before making big changes. It’s a great model to build with.”

    Tom Pritchard, Staff Engineer, in Claude Code

    “On our Super-Agent benchmark, Claude Opus 4.8 is the only model to complete every case end-to-end, beating prior Opus models and GPT-5.5 at parity on cost. For agent products in translation, deep research, slide-building, and analysis, it delivers powerful reliability.”

    Kay Zhu, Co-Founder and CTO, on the Super-Agent benchmark

    “On CursorBench, Claude Opus 4.8 exceeds prior Opus models across every effort level. Tool calling is meaningfully more efficient, using fewer steps for the same intelligence, and it carries end-to-end tasks through.”

    Michael Truell, Co-Founder and CEO, on CursorBench results

    “Claude Opus 4.8 delivers the highest score recorded on our Legal Agent Benchmark, and is the first model to break 10% overall on the all-pass standard. For substantive legal work, that’s the kind of accuracy lift that translates directly into how much real attorney work our customers can hand off with confidence.”

    Niko Grupen, Head of Applied Research, on the Legal Agent Benchmark

    “Claude Opus 4.8 feels like a major quality-of-life update over Opus 4.7: faster, easier to collaborate with, and better at carrying context and style direction across a long session. Opus 4.8 is the model I kept trusting for work where voice, taste, and technical execution all have to happen side-by-side.”

    Katie Parrott, Staff Writer, on long writing sessions

    “Claude Opus 4.8 is the strongest computer-use and browser-agent model we’ve tested, scoring 84% on Online-Mind2Web, which is a meaningful jump over both Opus 4.7 and GPT-5.5. It stays reflective and on-task in the way our customers’ agent workloads need to be reliable end-to-end.”

    Miguel Gonzalez, Tech Lead, on computer-use and browser agents

    “Claude Opus 4.8 uses tools cleanly and follows instructions with the consistency our autonomous engineering workloads need to keep running unattended. It improves on Opus 4.6 and fixes the comment-verbosity and tool-calling issues we saw with Opus 4.7. This release from Anthropic translates directly into faster capability gains for engineers building on Devin.”

    Scott Wu, CEO, on building with Devin

    “On our long-running evals, Claude Opus 4.8’s analysis was consistently higher quality than prior Opus models. It finished faster and produced richer, more information dense outputs. Overall, a noticeably better signal to noise ratio. The biggest differentiator was Opus 4.8’s tendency to proactively flag issues with the inputs and outputs of an analysis, something other models routinely missed and left to the users to catch.”

    Michael Ran, Sr. Investment Associate, on long-running analysis evals

    Claude Opus 4.8 is a quieter release than its “modest but tangible” billing suggests, because the gains land where autonomous work actually lives: a model that flags its own uncertainty, runs longer and checks itself, scales effort on demand, and stays affordable while fast mode gets cheaper. The honesty improvement alone changes the trust math for anyone deploying agents. Read Anthropic’s full announcement here.

    Related Reading

  • Claude Opus 4.7 Released: Anthropic’s New Coding Powerhouse With xhigh Effort Mode, 3.75MP Vision, and State-of-the-Art Agentic Performance

    TLDR

    Anthropic released Claude Opus 4.7 on April 16, 2026, as a direct upgrade to Opus 4.6. It delivers major gains on the hardest coding tasks, introduces a new xhigh effort level, supports images up to 2,576 pixels on the long edge (roughly 3.75 megapixels), and ships with automatic cybersecurity safeguards. Pricing stays flat at $5 per million input tokens and $25 per million output tokens. Early testers at Cursor, Replit, Vercel, Notion, Devin, Harvey, Databricks, and Warp report double-digit benchmark jumps, stronger instruction following, better long-horizon autonomy, and a more opinionated model that pushes back instead of agreeing reflexively.

    Key Takeaways

    • Direct upgrade from Opus 4.6 at the same price point, available via API as claude-opus-4-7, plus Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry.
    • New xhigh effort level slots between high and max, giving developers finer control over the reasoning-versus-latency tradeoff.
    • Vision gets a real jump: images up to 2,576 pixels on the long edge, more than 3x prior Claude models. XBOW reported 98.5% visual acuity versus 54.5% for Opus 4.6.
    • Coding benchmarks up across the board: Cursor saw 70% on CursorBench versus 58% for 4.6, Rakuten-SWE-Bench resolved 3x more production tasks, and GitHub measured a 13% lift on their 93-task benchmark.
    • Long-horizon autonomy is a headline theme. Devin says Opus 4.7 works coherently for hours. Genspark highlights loop resistance and the highest quality-per-tool-call ratio they have measured.
    • Instruction following is substantially tighter, which means old prompts written for loose-interpretation models may now behave unexpectedly. Re-tune prompts and harnesses.
    • Better memory across file-system-based workflows, reducing the need for up-front context in multi-session work.
    • Tokenizer changed: same input can now map to 1.0 to 1.35x more tokens. Opus 4.7 also thinks more at higher effort levels, so output token counts rise too.
    • Cybersecurity safeguards automatically detect and block prohibited or high-risk cyber requests. Legitimate security researchers can apply to the new Cyber Verification Program.
    • Claude Code gets /ultrareview, a dedicated review session that catches bugs and design issues. Pro and Max users get three free ultrareviews. Auto mode is extended to Max users.
    • State-of-the-art on GDPval-AA, a third-party evaluation of economically valuable knowledge work spanning finance, legal, and other domains.
    • Not the most capable overall model. That distinction still goes to Claude Mythos Preview, which also remains the best-aligned model Anthropic has trained.

    Detailed Summary

    What Claude Opus 4.7 Actually Is

    Claude Opus 4.7 is Anthropic’s latest generally available frontier model, positioned as a targeted upgrade to Opus 4.6 rather than a ground-up new generation. The focus is squarely on advanced software engineering, long-running agentic workflows, and higher-fidelity vision. Anthropic describes it as handling complex, long-running tasks with rigor and consistency, paying precise attention to instructions, and devising ways to verify its own outputs before reporting back.

    The positioning matters. Claude Mythos Preview, announced alongside Project Glasswing, remains the most powerful and best-aligned model Anthropic has trained. Opus 4.7 is the first release after Mythos Preview and serves a dual purpose: give developers a concrete upgrade today, and stress-test new cybersecurity safeguards on a less capable model before Anthropic attempts a broader release of Mythos-class systems.

    Coding and Agentic Performance

    The early-access testimonials read like a highlight reel of the agentic coding ecosystem. Cursor saw CursorBench scores jump from 58% on Opus 4.6 to over 70% on Opus 4.7. Rakuten measured 3x more resolved production tasks on Rakuten-SWE-Bench with double-digit gains in code quality and test quality. GitHub measured a 13% lift on a 93-task coding benchmark including four tasks that neither Opus 4.6 nor Sonnet 4.6 could solve. Notion observed a 14% improvement over Opus 4.6 at fewer tokens and a third of the tool errors, calling it the first model to pass their implicit-need tests.

    Devin emphasized sustained autonomy, saying the model works coherently for hours and pushes through hard problems rather than giving up. Warp reported that Opus 4.7 passed Terminal Bench tasks prior Claude models had failed, including a tricky concurrency bug Opus 4.6 could not crack. Vercel highlighted a behavior they had not seen before: the model actually does proofs on systems code before starting work, and is noticeably more honest about its own limits.

    A recurring theme across testimonials is that Opus 4.7 pushes back. Replit’s president said it feels like a better coworker because it challenges technical decisions instead of agreeing by default. Augment Code noted it brings a more opinionated perspective rather than simply agreeing with the user. For anyone building real engineering workflows, that pushback behavior is arguably more valuable than raw benchmark deltas.

    Vision: The Quiet Breakthrough

    The vision upgrade may be the most underappreciated change. Opus 4.7 now accepts images up to 2,576 pixels on the long edge, roughly 3.75 megapixels, which is more than three times the previous Claude limit. This is a model-level change, not an API parameter, so every image sent to Claude is processed at higher fidelity automatically.

    XBOW, which builds autonomous penetration testing agents that rely heavily on computer use, reported the most dramatic single number in the entire announcement: 98.5% on their visual acuity benchmark versus 54.5% for Opus 4.6. They described their single biggest Opus pain point as effectively disappearing, unlocking an entire class of work where they could not previously use Claude. Solve Intelligence reported major improvements in multimodal understanding for life sciences patent workflows, from reading chemical structures to interpreting complex technical diagrams.

    This unlocks computer-use agents reading dense screenshots, data extraction from complex diagrams, and any work requiring pixel-perfect references.

    The New xhigh Effort Level

    Opus 4.7 introduces an xhigh (extra high) effort level that sits between high and max. This gives developers a new middle gear for the reasoning-versus-latency tradeoff on hard problems. In Claude Code, Anthropic raised the default effort level to xhigh across all plans. For coding and agentic use cases, Anthropic recommends starting with high or xhigh effort rather than defaulting to medium.

    Alongside effort controls, the Claude Platform is getting task budgets in public beta, letting developers guide Claude’s token spend so it can prioritize work across longer runs. This matters because Opus 4.7 thinks more at higher effort levels, particularly on later turns in agentic settings.

    Token Usage Changes You Need to Plan For

    Two token-related changes affect migration. First, Opus 4.7 uses an updated tokenizer that improves how the model processes text, but the tradeoff is that the same input can map to 1.0 to 1.35x more tokens depending on content type. Second, Opus 4.7 thinks more at higher effort levels, which means more output tokens on hard problems.

    Anthropic’s own internal coding evaluation shows the net effect is favorable when measured against quality delivered per token, but the recommendation is to measure the difference on real traffic rather than assume. Token usage can be controlled via the effort parameter, task budgets, or simply prompting the model to be more concise. Anthropic published a migration guide with tuning advice.

    Claude Code Updates: /ultrareview and Auto Mode

    Claude Code gets two meaningful additions. The new /ultrareview slash command produces a dedicated review session that reads through changes and flags bugs and design issues that a careful reviewer would catch. Pro and Max users get three free ultrareviews to try it out.

    Auto mode, a permissions option where Claude makes decisions on behalf of the user so longer tasks run with fewer interruptions, has been extended from Pro to Max users. The pitch is that auto mode is safer than skipping all permissions while still enabling long autonomous runs.

    Cybersecurity Safeguards and the Cyber Verification Program

    Opus 4.7 ships with safeguards that automatically detect and block requests indicating prohibited or high-risk cybersecurity uses. During training, Anthropic experimented with efforts to differentially reduce cyber capabilities, meaning Opus 4.7’s cyber ceiling is intentionally lower than Mythos Preview’s.

    For legitimate users, Anthropic launched a Cyber Verification Program for security professionals doing vulnerability research, penetration testing, and red-teaming. Real-world data from these safeguards will inform how Anthropic eventually releases Mythos-class models more broadly.

    Safety and Alignment

    Opus 4.7 shows a similar safety profile to Opus 4.6 overall. Honesty and resistance to prompt injection attacks improved. Some measures slipped modestly, notably a tendency to give overly detailed harm-reduction advice on controlled substances. Anthropic’s alignment assessment concluded the model is largely well-aligned and trustworthy, though not fully ideal. Mythos Preview still holds the crown as the best-aligned model according to Anthropic’s evaluations. The full Claude Opus 4.7 System Card has the complete breakdown.

    Real-World Work Beyond Code

    Opus 4.7 posts a state-of-the-art score on the Finance Agent evaluation and on GDPval-AA, a third-party evaluation of economically valuable knowledge work spanning finance, legal, and other domains. Harvey reported 90.9% on BigLaw Bench at high effort with noticeably smarter handling of ambiguous document editing tasks, including correctly distinguishing assignment provisions from change-of-control provisions. Databricks measured 21% fewer errors than Opus 4.6 on OfficeQA Pro document reasoning. Vercel went as far as calling it the best model in the world for building dashboards and data-rich interfaces.

    Pricing and Availability

    Pricing holds at $5 per million input tokens and $25 per million output tokens. Opus 4.7 is live today across all Claude products, the Claude API as claude-opus-4-7, Amazon Bedrock, Google Cloud Vertex AI, and Microsoft Foundry.

    Thoughts

    The most interesting thing about this release is not the benchmark deltas, which are strong but expected for a point-release. It is the behavioral shift. When a dozen independent companies describe the same model as opinionated, willing to push back, self-verifying, and honest about its limits, that is a different product category than “next version, slightly better.” That is a model optimized for being a collaborator rather than an autocomplete.

    For solo builders running long agentic sessions, the loop resistance and long-horizon autonomy claims are the ones worth taking seriously. Genspark’s framing is sharp: a model that loops indefinitely on 1 in 18 queries wastes compute and blocks users. If Opus 4.7 genuinely closes that failure mode, the economics of overnight autonomous runs change meaningfully.

    The vision jump is the sleeper feature. 3.75 megapixel support plus the XBOW acuity number suggests computer-use agents are about to get a lot more reliable at reading actual screens. Anyone building browser agents, automated QA, or visual data extraction pipelines should retest their stacks this week.

    The instruction-following tightening is a real gotcha. Prompts written against Opus 4.6’s looser interpretation habits may produce surprising results when the model now takes every word literally. Teams with production prompt libraries should budget time for re-tuning rather than expecting a drop-in swap.

    Finally, the strategic framing around Mythos Preview is worth noting. Anthropic is explicitly using Opus 4.7 as a safeguards testbed for eventually releasing more capable cyber-capable systems. That is an honest acknowledgment that capability and deployment readiness are separate problems, and it sets a template for how frontier releases may work going forward.