Normal view

Anthropic’s new browser tool doesn’t actually run a browser

Abstract digital art of glowing cyan and magenta data particles flowing along curved paths on a dark background, representing network traffic and cloud infrastructure.

Anthropic launched a new Browser Use tool that gives Claude a structured view of a web page in addition to what is visually rendered. Announced Thursday, the tool uses the page’s accessibility tree to help Claude find and interact with specific elements directly rather than having to work out where they are on the screen.

Browser Use is part of a broader Anthropic release that also brings Computer Use, the Skills API and Files API into general availability. Developers can access the browser tool through the Claude API using browser_toolset_20260801.

Browser Use is part of a broader Anthropic release that also brings Computer Use, the Skills API and Files API into general availability.

The change gives Claude a more direct way to interact with a web page. Instead of working out a button’s position from a viewport image and targeting coordinates such as x: 640, y: 320, Claude can receive a reference such as ref_3 tied to that element and use it when it wants to act.

Page references replace coordinates

Computer Use can operate across an entire desktop by looking at screenshots and sending mouse coordinates and keyboard commands. Browser Use works within the browser itself, where it can use page structure that would be difficult to recover reliably from pixels alone.

When Claude calls read_page, the developer’s executor returns a text representation of the accessibility tree, in which elements such as links, buttons, and text boxes can be tagged with references. If Claude later wants to click a button represented by ref_3, it can send that reference along with the requested operation rather than trying to calculate where the button is on the screen.

That said, if the tab navigates to a new page or the page changes enough, a reference that pointed to a button a moment ago may no longer work. The API will not catch that on its own, so the executor has to recognize when the reference no longer matches the underlying element, reject the action and have Claude read the page again before continuing.

Batching cuts model calls

Playwright, for example, can represent a page as an ARIA snapshot and locate elements by role rather than coordinates. At the same time, Microsoft’s Playwright MCP server already exposes structured accessibility snapshots with references a model can use to identify elements. The concepts line up closely with Browser Use, but the protocols do not: Playwright MCP speaks MCP, while Anthropic’s tool uses its own client-toolset protocol, so developers would still need an adapter that translates Claude’s requests into Playwright actions and returns the results in the format Claude expects.

Puppeteer offers many of the same building blocks, exposing the browser’s accessibility tree via Accessibility.snapshot() and providing APIs for controlling Chrome and Firefox. A developer could use those APIs for navigation or page reads, then maintain Anthropic’s reference mappings on top.

A developer could use those APIs for navigation or page reads, then maintain Anthropic’s reference mappings on top.

Slightly confusing, an unrelated open-source project also called Browser Use runs AI browser agents against Chromium through the Chrome DevTools Protocol. Despite the shared name, it has no connection to Anthropic’s tool and comes with its own agent loop and browser abstractions, so connecting the two would still require integration work.

Several browser actions can happen in one turn

Anthropic is also reducing the back-and-forth between Claude and the browser by allowing multiple actions to be requested in a single model turn. Now actions can arrive together as several tool_use blocks. The application executes them in order and sends the results back together, avoiding another model call between every click and keystroke. Anthropic says that can lower latency and costs, particularly as workflows scale from a handful of interactions to dozens or hundreds.

That matters more as browser tasks get longer. Cheaper models alone will not solve the token cost problem in agentic workflows, so cutting unnecessary model calls is another way to reduce costs.

If Claude has to return to the model after every click or keystroke, a long browser task can quickly rack up model calls. Batching cuts out some of that back-and-forth by letting Claude request several actions at once, but the browser still has to carry them out in order because each one depends on what happened before it. If Claude asks to click a button, fill in a field, and submit a form, for example, the executor cannot simply move on to the next step if that first click fails, because everything that follows is now based on a page state Claude never reached.

Batching cuts out some of that back-and-forth by letting Claude request several actions at once, but the browser still has to carry them out in order because each one depends on what happened before it.

Developers host the browser

Browser Use is currently limited to the Claude API and is not available inside Claude Managed Agents. Adding it to a Messages API request exposes 27 browser operations by default. Claude can decide which of those operations it wants to use, but Anthropic does not execute them. The application has to translate each request into an action inside its own browser environment, preserve the session between turns and return enough information for Claude to understand what happened.

Loading all of those operations has a token cost. Anthropic’s pricing documentation says the default Browser Use toolset adds roughly 6,600 input tokens to a request, before counting screenshots, accessibility trees and other results sent back to Claude. Developers can turn off operations they do not need to reduce that overhead.

It also creates a different hosting split from some of the other tools Anthropic announced Thursday. Skills uploaded through the Skills API can run inside Anthropic’s code execution sandbox, while the Files API stores documents that can be reused by ID. Browser sessions, along with their downloads and uploaded files, stay in the developer’s environment.

Approval gates need rethinking

Claude can still encounter a prompt injection in web content or be redirected to an unexpected location, which is why Anthropic recommends running the browser in an isolated container or virtual machine with minimal access. JavaScript and file uploads should remain disabled unless needed, since code generated by Claude runs with the page’s privileges and can reach data or make requests available to that page.

Batching makes approval a little trickier because several actions can arrive at once, and a routine click at the beginning of a sequence could eventually lead to something that requires the user’s permission. That means the executor has to check actions as they happen and stop for approval when needed.

The post Anthropic’s new browser tool doesn’t actually run a browser appeared first on The New Stack.

Forget the model wars, Stripe and Ramp just started the router wars

I’m Matt Burns, Chief Content Officer at Insight Media Group. Each week, I round up the most important AI developments, explaining what they mean for people and organizations putting this technology to work. The thesis is simple: workers who learn to use AI will define the next era of their industries, and this newsletter is here to help you be one of them.


Model triage is becoming one of the most important skills for the AI-native developer. I’ve argued all summer that the people getting the most out of frontier models are the ones disciplined enough not to run the best model by default. On Wednesday, Stripe and Ramp validated that idea 70 minutes apart: Stripe bought OpenRouter, and Ramp released its internal router.

Bloomberg puts the OpenRouter price tag above $7 billion, and Axios says it’s more than $8 billion in cash and stock. Stripe has not released the terms, so the details remain fuzzy.

While the acquisition made headlines, the architecture is the story. For the last couple of years, picking a model was something written into an application, a string in a config file, and swapping models took some work. A router changes that workflow. Stripe bought the layer, and Ramp built it. Both are betting their existing relationships give them a unique wedge to own this critical layer in the new AI stack.

Picking a model is becoming a runtime decision

OpenRouter is an endpoint serving more than 400 models from over 80 providers, processing more than 10 trillion tokens a day. Andrej Karpathy calls it the transfer switch for AI. Ramp’s Router does the same job on a smaller catalog and claims roughly 40% lower cost for the same output.

Both are betting the model name in a codebase is a liability. They’re mostly right. Back in June, I pointed to Mitchell Hashimoto, who found a standard coding task that cost about $1.50 on GPT-5.5 and roughly $9 on Claude Fable, with both producing equally acceptable results. A router automates that triage, making decisions on every request rather than only on those a developer explicitly configures.

This is becoming a large problem and a large opportunity. Our own Amanda Caswell reported this week that Anthropic’s /claude-api skill was burning about 200,000 tokens before answering a single question, and that loading its reference docs on demand instead of up front cut that to roughly 25,000. Hafiz Hassan wrote for us last week about why AI pipelines cost 10x more than the demo, and every culprit on his list is an engineering decision: system prompts resent every turn, whole conversation histories appended, oversized RAG chunks, raw JSON dumped into context. It’s a great practical guide, and none of the items Hassan identifies are procurement problems.

The token bill is generated by your code, which is why the tools to control it are arriving there as well.

Stripe and Ramp want the same layer for opposite reasons

Stripe is attacking the problem from the bottom up, through developers. The company’s investor letter, leaked Wednesday by Eric Newcomer, makes the argument directly: “Up until now, every developer has needed a straightforward and reliable way to manage their revenue pipeline, and serving this need gave rise to Stripe. Going forward, however, every developer will also need a straightforward and reliable way to manage their intelligence pipeline.”

Stripe wants to control AI spending through the long tail of developers. Ramp wants to control it through its existing relationship with finance.

Stripe has built this product before. Its payments business hides dozens of local payment methods behind a single API, routing each transaction to the payment method most likely to convert. The AI version is the same idea applied to models instead of payment networks.

Ramp is attacking it from the top down, through finance. The company bought the router.com domain and says its customers already buy quadrillions of tokens a month through Ramp. Founder Veeral Patel’s launch post pitches the service simply: “Monitor and control your AI bill across every provider.” Adam Wazzan sums up Ramp’s strategy better than I can: “when a CFO ships a product for CTOs.”

Stripe wants to control AI spending through the long tail of developers. Ramp wants to control it through its existing relationship with finance. Both are chasing what is rapidly becoming one of the largest line items in corporate technology budgets: tokens.

On X, Kabir Goel pushes back on Stripe’s framing. Routing tokens is a way to spend less, while Stripe’s other products are designed to help businesses make more. 

“Stripe is just not where teams go to understand how much they’re spending,” he writes. “That’s pretty squarely Ramp territory.” 

He has a point about where teams look today. Whether that’s still true three years from now is exactly what Stripe just spent billions betting against.

The router worth pointing at is the one with no model to sell

Whichever router you point at decides which model writes your code, and not every router is disinterested. Our own Paul Sawers flagged the problem in July when he covered the first wave of Cursor’s, Ramp’s, and Meta’s routers. Cursor backs Grok and Composer. Meta is building Muse Spark. Both have reasons to send work to their own models, and Paul quoted developer Elvis Saravia asking whether routing logic ought to be open source rather than a vendor’s private judgment call.

Stripe and Ramp do not sell models. OpenRouter CEO Alex Atallah says as much in Stripe’s own announcement: Developers “need a neutral layer to orchestrate and manage them all.” Investor Gavin Baker frames the opportunity the same way, arguing that Stripe can become the neutral infrastructure layer for AI, just as it became the neutral infrastructure layer for payments. 

Neutrality isn’t free, though. Stripe takes a percentage of token spend, and Ramp wants your spending relationship, so “free through 2026” is a customer acquisition strategy with an expiration date.

The obvious objection is that vendor motives are the wrong thing to worry about, and routing quality is what really matters. That’s fair, and Towards Data Science published one of the best practical examples I’ve read. Pratik Rupareliya describes a routing layer that cut a support agent’s inference bill by 40% but also broke the product. A classifier sent “simple” queries to a cheaper model, but some of those “simple” queries were actually fraud investigations. 

The cheaper model answered them confidently and incorrectly. Customers stopped using the agent, churn rose above baseline in month four, and retention costs were four to five times higher than the savings. It took three months to surface and another month to identify the cause. His fix was per-tier quality monitoring combined with an uncertainty-routed cascade, which ultimately settled at 35% savings without sacrificing quality. It’s an excellent article to read before diving into model routing.

So instrument the routing. Log what the router picks on every request and break out your quality metrics by the model that served them. Ramp Router reportedly records the model, provider, tier, tokens, latency, cost, and fallback attempts for every call. Stripe OpenRouter rankings have been a public version of that telemetry for years. You can get similar visibility with either approach.

Right now, the model is becoming an implementation detail. The competition is shifting to the layer that decides which model gets the job. Stripe and Ramp are betting that developers won’t care what sits behind the endpoint, so long as the bill is lower and the results are good enough. 

The post Forget the model wars, Stripe and Ramp just started the router wars appeared first on The New Stack.

❌