What is "Vibe Business Building" — The Three-Stage Evolution of an Idiom That Started with Karpathy

To understand the concept of "Vibe Business Building," one must trace its lineage. The starting point was February 2025, when Andrej Karpathy—former OpenAI co-founder and former head of Tesla AI—casually posted the phrase "Vibe Coding" on X (formerly Twitter). This coined term referred to a new development style of "conveying intent in natural language and having AI write the code," and it instantly became standard vocabulary in the engineering industry. According to Wikipedia's "Vibe coding" entry, the concept swept through developer culture throughout 2025, and as of March 2026, 82% of developers reported using or planning to use AI coding tools.

However, in February 2026, Karpathy himself declared on X that "vibe coding is now passé," and proposed a new term: "Agentic Engineering." According to The New Stack, Karpathy stated, "LLM capabilities have improved dramatically, and the time humans spend writing code has dropped to less than 1%. Going forward, the essential engineering skill is designing and supervising multiple AI agents." His multi-model coordination project "LLM Council," released as a weekend hack, was described by VentureBeat as having "sketched out the missing middleware layer for enterprise AI orchestration in just a few hundred lines of Python/JavaScript."

Along this same trajectory, Scott White, Anthropic's head of enterprise products, told CNBC at the February 2026 launch of Claude Opus 4.6 that "we are now transitioning into the era of Vibe Working." Just as Vibe Coding opened the door for non-engineers to write software, Vibe Working signifies a world where anyone can produce polished, professional deliverables simply by expressing their intent. Then in April 2026, these currents were integrated into a single practical concept: "Vibe Business Building." This refers to a way of working in which all phases of new business development (NBD)—from code generation, document creation, and data analysis to market validation and customer interview design—are delegated to AI via natural language interfaces, while humans focus exclusively on decision-making and quality judgment.

Why PoC Budgets Get Compressed to One-Tenth——Dismantling the Cost Structure

The conventional approach to new business PoC in Japan typically involved 2–3 engineers embedded for 3–6 months, with additional outsourcing to external research firms and contract development companies. According to 2026 MVP cost surveys by overseas development firms such as RaftLabs and Softermii, a typical AI-integrated PoC runs from €50,000 to €250,000 (approximately ¥8.1M–¥40.5M), with complex configurations exceeding $150,000 (approximately ¥22.5M). A report by Japanese firm landbridge noted that a representative PoC in new business development costs around ¥4M per month with a 10-person team, amounting to roughly ¥50M annually.

With the emergence of Vibe Business Building, however, this structure has been compressed by a literal order of magnitude. In the outlook piece "Notes on AI Apps in 2026" published by a16z in early 2026, the firm explicitly stated that "the cost of intelligence has dropped 10x per year over the past three years — down 99.7% over two years." a16z partner Anish Acharya said on The Twenty Minute VC podcast that "the cost of validating an idea has fallen 95%, and you can now test 10x more hypotheses with the same capital," while Marc Andreessen himself has stated that "founders who can validate product-market fit in 90 days rather than 9 months will win."

Looking at the specific breakdown: Anthropic released Claude Sonnet 4.5 in December 2025 and Claude Opus 4.6 in February 2026, pricing them at $5 input / $25 output (per million tokens, approximately ¥750/¥3,750). This represents a 67% price reduction from the Opus 4.1 generation's $15 input / $75 output (approximately ¥2,250/¥11,250). Furthermore, the prompt caching feature enables up to 90% cost reduction for repeatedly referenced context, and the Batch API offers 50% off for asynchronous processing — combined, these enable a 95% compression in costs.

In the case of Japan's Transcosmos, which presented its "VibeOps Method" at Developers X Summit 2025, combining Cursor, v0, and Vercel resulted in a 5x improvement in development speed. A PoC that previously required a 10-person team at ¥4M/month became operable with a 3-person team at ¥1.2M/month, achieving ¥33.6M in annual savings with a 3.6-month payback period. A 2026 Forrester Research survey of enterprise development teams across 500 companies similarly reported that AI assistance reduced time spent on routine coding tasks by 42%, cut total development costs by 32%, and decreased post-production bug-fix costs by 42%. Taken together, these developments have made real the kind of compression practitioners describe as "one-tenth" — PoC budgets shrinking from tens of millions of yen to single-digit millions, and timelines from months to weeks.

The Protagonist: Anthropic — On April 7th, Surpassing OpenAI with $30 Billion ARR

At the center of this VBB wave is Anthropic. On February 12, 2026, Anthropic officially announced the completion of a $30 billion Series G led by GIC and Coatue, reaching a post-money valuation of $380 billion. Co-leads included D. E. Shaw Ventures, Dragoneer, Founders Fund, ICONIQ, and MGX, with existing major shareholders such as Sequoia and Menlo Ventures also participating in follow-on investments. Crunchbase News reported this as more than double the valuation of $170 billion at the end of 2025, making it the second-largest venture funding round in history.

The subsequent growth traces an exceptional trajectory, just as Axios wrote that "no company in American corporate history has grown like Anthropic." According to a SaaStr article, ARR climbed from $1 billion in December 2024 to $9 billion by end of 2025, $14 billion in February 2026, $19 billion in March, and $30 billion by April 7. This represents more than a threefold increase in three months, surpassing OpenAI's $25 billion at that point and placing Anthropic at the top among generative AI companies. In Anthropic's own announcements, the number of enterprise customers paying more than $1 million annually more than doubled — from just over 500 in February 2026 to over 1,000 in April, just two months later. Enterprise revenue accounts for approximately 80% of the total, in stark contrast to OpenAI's more consumer-weighted revenue mix.

Claude Code, a core driver of VBB, is also showing extraordinary growth. According to Builtin, Claude Code reached $1 billion in annualized revenue just six months after its general availability launch in May 2025, and surpassed $2.5 billion within nine months. This marks the fastest milestone achievement in enterprise software history, with a single product accounting for more than half of Anthropic's enterprise revenue.

Then on April 8, 2026, Anthropic announced a new public beta called "Claude Managed Agents." As TechRadar reported, it is an integrated platform that promises to "reduce the time from prototype to production deployment from months to days" and "make agent building 10x faster," coming with production-grade sandboxing, authentication, and tool execution built in from the start. On the same day, Claude Cowork (formerly Claude for Work, a desktop-resident team workflow automation product) shed its "research preview" label and was elevated to an official enterprise release, with governance features including role-based access control, group spending limits, OpenTelemetry-based observability, and Splunk and Cribl integrations all added at once. VentureBeat's Kari Johnson remarked, "If Claude Code changed vibe coding for developers, Claude Cowork changes work for everyone else."

How Silicon Valley VCs Are Receiving It — Three Different Perspectives

Silicon Valley VCs' reactions to VBB are far from monolithic. Rather, three distinct positions have emerged, each reflecting the investment philosophy of individual firms.

a16z — The cautious view: "Use it for core business, not back office"

Anish Acharya, General Partner at Andreessen Horowitz, stated clearly on the "20VC" podcast: "Software is only 8–12% of enterprise costs. Even if you vibe-code payroll and ERP, you'll save maybe 10% of that. Why direct AI toward rebuilding payroll, ERP, and CRM instead of the other 90% of the cost structure?" Acharya dismissed the notion outright — "Nobody wants to vibe-code their own payroll" — and argued that companies should avoid compliance risk and focus on differentiating their core business.

Within the same firm, partner Olivia Moore publishes a monthly tracking piece, "Top 100 Gen AI Consumer Apps," and noted in the March edition that vibe coding platform Replit ranked in the top three apps, commenting that "whether this space consolidates into a monopoly or retains multiple players is the biggest open question going forward." a16z closed a new $15 billion fund in January 2026, bringing total AUM to $90 billion and putting it on par with Sequoia. As an investment theme, the firm views VBB in three layers — "v1.0 (consumer prototyping)," "v2.0 (core business creation)," and "v3.0 (workflow automation)" — with v1.0 and v2.0 as its primary battlegrounds.

Emblematic of a16z's 2026 consumer AI thesis is its $20 million pre-seed investment in Wabi, led by Eugenia Kuyda. Wabi is a platform that "generates apps from prompts and iterates through UI rather than code," and a16z has described it as democratizing software creation the way YouTube democratized content creation.

Sequoia Capital — The bold view: a multi-trillion-dollar "Agent Economy"

Sequoia Capital partner Konstantine Buhler, speaking on Bloomberg in January 2026 and in the firm's "Inference by Sequoia" newsletter, paints a more ambitious picture of an "Agent Economy." According to Buhler, AI agents will not merely relay information but will "transfer resources, execute transactions, and form their own economic sphere with mutual understanding of each other's trustworthiness" — a market he estimates will be "10 times the size of cloud computing, meaning trillions of dollars."

Buhler remarked, "Many of us loved computer science because it was deterministic. But now we are entering the era of stochastic computing," and argued that both companies and investors must make this psychological shift. Sequoia continued its participation in Anthropic's Series G in February 2026, holds a position in OpenAI as well, and ranked among the top-tier investors in Crunchbase News's "Most Active VC Investors" list for 2025. "Rox," an agentic CRM in Sequoia's portfolio — built around the idea of giving "every sales rep a swarm of agents" — is a textbook example of VBB in practice.

Menlo Ventures, Founders Fund, and others — The "Anthology Fund" model, directly tied to Anthropic

Menlo Ventures is a major existing shareholder in Anthropic and, in July 2024, co-launched with Anthropic a $100 million AI-focused vehicle called the Anthology Fund. The Anthology Fund writes checks across a broad range of stages from pre-seed to Series, and provides portfolio companies with $25,000 in Anthropic model usage credits. Menlo's blog post titled "Tripling Down on Anthropic" speaks candidly about the firm's conviction in Anthropic's future.

In December 2025, Anthropic launched its "Anthropic VC Partner Program" to organize the VC layer, enabling portfolio companies to receive Claude credits, priority API rate limits, and dedicated support directly. Then on March 12, 2026, the firm committed $100 million to the "Claude Partner Network," anchoring it with major systems integrators such as Accenture, Deloitte, Cognizant, and Infosys. HFS Research characterized this move as "Anthropic now attempting to absorb the IT services industry itself."

The decisive development came on April 10, 2026, when CorpDev.Org and TechFundingNews reported on a "200 Million Private Equity Alliance." Anthropic is contributing $200 million of its own capital and has organized a joint venture drawing $1 billion in total from major buyout firms including Blackstone, Hellman & Friedman, Permira, and General Atlantic, with plans to embed Claude directly into those PE firms' portfolio companies. The approach is said to reference Palantir's "forward-deployed engineer" model, and CorpDev.Org has framed it as "a new blueprint for AI commercialization."

Key Products and Investment Map of the VBB Ecosystem

In the implementation layer of Vibe Business Building, numerous specialized tools have formed a major ecosystem around Claude Code. Let us survey each one's characteristics along with their latest valuations and ARR figures.

One of the most prominent is Cursor, offered by Anysphere, which raised $2.3 billion (approximately ¥345 billion) at the end of 2025, reaching a valuation of $29.3 billion (approximately ¥4.4 trillion), and surpassed $2 billion ARR (approximately ¥300 billion) in Q1 2026. The round was led by Sequoia with participation from Accel, a16z, and Founders Fund. Cursor has established itself as a productivity-enhancing tool for engineers, with particular strengths in code comprehension and debugging.

Lovable, founded in Sweden, completed a $330 million Series B (approximately ¥49.5 billion) in December 2025 led by CapitalG and Menlo Ventures, reaching a valuation of $6.6 billion (approximately ¥990 billion), before hitting $400 million ARR (approximately ¥60 billion) in February 2026. According to AI Business Review, Lovable achieved this revenue with just 146 employees, and the speed at which it reached this milestone in under a year since founding is said to be the fastest in software history. Its defining positioning is "generating entire web applications end-to-end from natural language."

Replit closed a $400 million Series D (approximately ¥60 billion) on March 11, 2026, led by Georgian Partners, reaching a valuation of $9 billion (approximately ¥1.35 trillion). This represents a tripling from September of the prior year, and according to TechCrunch, CEO Amjad Masad has publicly stated he aims to "achieve $1 billion ARR (approximately ¥150 billion) within the year." Replit's agent functionality integrates with more than 30 services, and Olivia Moore described it as "the most autonomous builder."

Bolt.new from StackBlitz, announced by Eric Simons and his team at the end of 2024, reached $40 million ARR (approximately ¥6 billion) in just 4.5 months, and in January 2025 secured a valuation of $700 million (approximately ¥105 billion) in a round led by Emergence Capital and GV (formerly Google Ventures). Its strength in instantly generating UI from screenshots is a defining feature, and Lenny Rachitsky called it "one of the fastest-growing products in history."

Vercel's v0 originally launched in October 2023 as a UI component generator, then rebranded as v0.app in January 2026 to support full-stack development. Its appeal lies in its integration with the Next.js ecosystem—Vercel's core strength—and it continues to hold an advantage in the frontend space.

Somewhat different in character is Wabi, which received a $20 million pre-seed investment (approximately ¥3 billion) from a16z and is building a platform to create "personal software" for consumers. The combination of Eugenia Kuyda's (known for Replika) consumer intuition and a16z's backing makes it a symbol of the "2.0 generation" of VBB.

The relationship between these tools and Anthropic is both complementary and competitive. Trending Topics has reported that "Anthropic is internally developing a vibe-coding product to rival Lovable," and while Claude Code itself is penetrating Cursor and Bolt workflows, Anthropic is pursuing a dual strategy of also partnering with these third parties at the API level.

Coverage tone of major media and industry analysts

Each media outlet's stance on VBB differs clearly based on their respective editorial characteristics.

VentureBeat and TechRadar, as stalwarts of technology journalism, positively covered Anthropic's claims about Claude Managed Agents and the official release of Cowork — phrases like "from months to days" and "10x faster" — while specifically listing early adopters such as Notion, Asana, and Sentry. VentureBeat's article title, "Claude Code transformed programming. Now Claude Cowork is coming for the rest of the enterprise," succinctly captures the expansion from the developer domain into the non-engineer enterprise space.

CNBC, in its April 11, 2026 report from the AI industry conference "HumanX" held in New York, used the phrase "Claude mania" to convey that attendees' attention was focused on Anthropic rather than OpenAI. The outlet also reported positively on the February 2026 launch of Claude Opus 4.6 as "a sign that AI is heading into the 'vibe working' era."

Axios, in an April 13 article, wrote that "no company in American corporate history has grown like Anthropic," framing the tripling of ARR from $900 million to $3 billion in three months as a historic event. Meanwhile, Axios reporter Jonathan Vannian, in a January feature titled "Cowork wrote itself," investigated the fact that Anthropic built the product in 1.5 weeks using Claude Code, placing significant weight on the reality of internal "dogfooding."

Fortune and Bloomberg, as business publications, treated the $380 billion valuation (approximately ¥57 trillion) and the $30 billion (approximately ¥4.5 trillion) Series G primarily as financial events, with attention focused on the possibility of an IPO. A Fortune article dated February 13, 2026 stated that "Anthropic has emerged as one of the largest IPO candidates in history, alongside OpenAI and SpaceX," while Trading Calendar and trading-focused media reported banker-sourced information suggesting "a possible Nasdaq listing in Q4 2026, with a valuation of $400–500 billion (approximately ¥60–75 trillion) and fundraising exceeding $60 billion (approximately ¥9 trillion)."

The New Stack and The Information, as specialized tech publications, offer deeper analysis. The New Stack traced in detail the shift to Agentic Engineering, starting from Karpathy's remark that "vibe coding is passé," and pointed out that enterprise adoption requires "professional legibility."

Within Japan, The Japan Times covered the ethical dimensions of the Anthropic–PE joint venture in a March 9, 2026 article, while practical implementation records from Japanese companies are increasingly appearing on Nikkei Cross Tech and Qiita. The KINTO Technologies blog (a Toyota affiliate), in a January 30, 2026 post titled "What happened when I tried to take over a PoC built with Vibe Coding — and lost a week," candidly shared pitfalls of Vibe Coding, including "over-reliance on code that merely runs" and "billing incidents caused by runaway external API calls," conveying the temperature of the implementation front lines.

Forrester Research and Gartner offered contrasting assessments in their early 2026 forecasts. Forrester presented positive figures — "a 32% reduction in total costs and 42% reduction in coding time with AI-assisted development" — while Gartner's 2026 forecast warned that "expectations for GenAI are declining due to high PoC failure rates, and CIOs are shifting toward scaling back PoCs and in-house development in favor of relying on GenAI features from existing software vendors." McKinsey's 2026 edition of its "State of Organizations" report noted that "more than 40% of companies are moving agentic AI from the pilot stage to scale," while BCG estimated that "corporate AI spending will double in 2026, representing a $200 billion (approximately ¥30 trillion) opportunity in the tech services sector alone." At the same time, BCG cautioned that "60% of organizations are failing to generate real value from their AI investments, with only 5% succeeding in creating scaled value," emphasizing the importance of operational governance alongside VBB's momentum.

Japan Market and Anthropic's Tokyo Base Strategy

Vibe Business Building is arriving rapidly in Japan as well. Anthropic opened its Tokyo office at the end of 2025 as its first base in the Asia Pacific region, and in early 2026 recruited Hidetoshi Tojo—who had held key positions at Microsoft, Snowflake, and Google Cloud Japan—as president of its Japanese subsidiary. Anthropic CEO Dario Amodei himself met with Prime Minister Sanae Takaichi and signed a Memorandum of Cooperation (MoC) with the AI Safety Institute.

At the implementation layer, Rakuten has significantly improved developer productivity through an autonomous coding project using Claude, and Nomura Research Institute (NRI) published a case study showing document analysis tasks reduced from several hours to minutes while maintaining accuracy. NRI received Japan's first certification as a Claude reseller on Amazon Bedrock in November 2025, and has been expanding its implementation support services for the Japanese market since January 2026. Panasonic is evaluating Claude in the area of supply chain optimization, and all three companies are cited in Anthropic's official blog as representative examples of "the region with the most Claude Code users in Japan."

At the startup layer, the "Builder Summit" held in Tokyo in October 2025 attracted over 150 startups and founders, and the official developer conference "Code with Claude: Extended Tokyo" is scheduled for June 11, 2026. From Japan's SI industry, the aforementioned Transcosmos is developing its "VibeOps Method," while Fujitsu and NTT Data are in the process of establishing similar internal guidelines.

Upcoming milestones to watch — what will happen and when

Integrating statements from Silicon Valley VC insiders and industry analysts, the moves expected to be observed over the next 12 months can broadly be organized along the following timeline.

Q2 2026 (April–June) is expected to see the transition of Claude Managed Agents to general availability (GA), along with full integration of enterprise plugins for Claude Cowork with Microsoft 365 and Google Workspace. The finalization and release of the Anthropic-Blackstone-Hellman & Friedman-Permira private equity joint venture agreement is also anticipated during this period. At the same time, Gartner warns in its Q2 2026 forecast report that "enterprise vibe coding/building will pass through a 'trough of disillusionment,' leaving only those cases equipped with proper operational governance to survive a period of selection."

Summer 2026 (July–September) is expected to see Anthropic file its S-1 (IPO prospectus) with the SEC, with Trading Calendar and investment information site estimates placing the public IPO valuation at $400–500 billion (approximately ¥60–75 trillion). During the same period, Claude's next-generation model "Claude Mythos" (reported by some media as having 10 trillion parameters) may emerge, likely elevating the autonomy of Vibe Business Building by another level. a16z has announced additional investment ahead of this period targeting "VBB 2.0 players in consumer software," making it highly probable that a third consumer-facing product will emerge following Lovable and Wabi.

Q4 2026 (October–December) is expected to see Anthropic list on Nasdaq. Simultaneously, in the enterprise market, verified cases of new business automation via Claude Cowork achieving "10%+ reductions in person-month costs" will accumulate, with a high likelihood that PwC, Deloitte, and Accenture's 2027 AI spending forecasts will significantly exceed expectations. In the Japanese market, NRI predicts that VBB assumptions will begin to be incorporated into new business development budget planning by listed companies, coinciding with the timing of mid-term management plan revisions that begin with the April new fiscal year.

2027 and beyond is expected to see the full launch of what BCG and Sequoia respectively refer to with the keywords "agent economy" and "Agentic Enterprise" — namely, an economic sphere in which agents transact with and compensate one another. Konstantine Buhler stated on Bloomberg that "2026 will be the year of evaluating returns on AI investment, and 2027 will be the year of reallocation based on those returns," suggesting that the competitive gap between companies that have mastered VBB at the PoC stage and those still clinging to conventional PoC projects in the tens of millions of yen could become decisive.

Summary — "PoC Budget Cut to 1/10" Is Just the Beginning

The concept of Vibe Business Building is not merely a cost-reduction measure, but a phenomenon that rewrites the very "cost asymmetry" inherent in new business development. As of April 2026, Anthropic has reached an annualized revenue of $30 billion and a valuation of $380 billion (approximately 57 trillion yen), moving across multiple fronts—Claude Cowork, Claude Managed Agents, Claude Partner Network, and PE joint ventures—with the aim of becoming the "VBB OS within the enterprise." a16z, while expressing cautious views, is accelerating investments in the consumer segment; Sequoia is throwing itself into the mega-trend of the "agent economy"; and Menlo Ventures is partnering directly with Anthropic to cultivate the startup layer.

The headline that PoC budgets are being cut to one-tenth is striking, but that is only the entry point. The real impact lies in redirecting those nine-tenths of freed-up budget toward "validating more hypotheses"—resulting in companies being able to test ten times as many ideas and engaging with the market at ten times the speed. Marc Andreessen of a16z's "90-day PMF," Sequoia Buhler's Agent Economy thesis, the fact that Garry Tan of Y Combinator repeatedly cites that "25% of YC's most recent batch is 95% AI-generated code," and Anthropic's extraordinary revenue growth curve all point to the same single inflection point. That is the dawn of an era in which the cost of "launching" a new business falls to its absolute minimum—the era of Vibe Business Building.

The implications for Japanese companies are clear. New business budgets for fiscal year 2026 should no longer be structured around "investing tens of millions of yen in a PoC to validate one or two concepts," but rather redesigned to "validate 20 to 30 concepts in parallel with the same budget and eliminate them based on data." Silicon Valley VCs differ individually in whether they welcome or are wary of this shift. Yet what they all agree on is the recognition that "2026 is the year Vibe Business Building entered the implementation phase on the enterprise front line, and there is no going back."

Summary — "PoC Budget 1/10" Is Just the Beginning

The concept of Vibe Business Building is not merely a cost-reduction measure, but a phenomenon that rewrites the very "cost asymmetry" in new business development. As of April 2026, Anthropic has reached an annualized revenue of $30 billion and a valuation of $380 billion (approximately ¥57 trillion), and is moving to become the "VBB OS within the enterprise" across multiple fronts: Claude Cowork, Claude Managed Agents, Claude Partner Network, and PE joint ventures. a16z is accelerating investment in the consumer segment while maintaining a cautious stance, Sequoia is throwing itself into the mega-trend of the "agent economy," and Menlo Ventures is cultivating the startup tier in direct partnership with Anthropic.

The headline that PoC budgets are being cut to one-tenth is striking, but it is only the entry point. The real impact lies in the ability to redirect those nine-tenths of saved budget toward "testing more hypotheses," and as a result, the number of ideas a company can try increases tenfold, and the speed of dialogue with the market increases tenfold. Marc Andreessen of a16z's "90-day PMF," Sequoia Buhler's Agent Economy thesis, the fact that Garry Tan of Y Combinator repeatedly cites that "25% of YC's recent batch is 95% AI-generated code," and Anthropic's extraordinary revenue growth curve — all of these point to the same single inflection point. That is the dawn of an era in which the cost of "launching" a new business falls to its absolute limit — the era of Vibe Business Building.

The implications for Japanese companies are clear. New business budgets for fiscal year 2026 should no longer be designed around "investing tens of millions of yen in a PoC to validate one or two ideas," but rather redesigned to "validate 20 to 30 ideas in parallel with the same budget and cull them based on data." Silicon Valley VCs differ individually on whether they welcome or are wary of this change. But what they all agree on is the recognition that "2026 is the year Vibe Business Building entered the enterprise implementation phase, and there is no going back."

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