Anthropic Launches Claude for Chrome Extension, Currently Available for Beta Testing to 1,000 Claude Max Subscribers

Anthropic has launched a pilot programme for its new Claude for Chrome extension. Integrated into the Chrome sidebar, the extension enables Claude to manage calendars, schedule meetings, summarise Google Docs and emails, draft responses, handle expense reports, find property listings, add items to shopping carts, and test website features. If you recall, Comet was launched with Comet Assistant, which offers similar capabilities but is limited to the Comet browser only.

The pilot programme is initially available to 1,000 Claude Max plan subscribers, a premium tier priced at $200 per month. Interested users can join the waitlist at claude.ai/chrome and, once granted access, install the extension via the Chrome Web Store after authenticating with their Claude credentials.

Despite its promising features, Anthropic highlights that browser-based AI introduces significant security challenges, particularly prompt injection attacks, where malicious instructions hidden in websites, emails, or documents can trick Claude into taking harmful actions. During internal testing, Anthropic evaluated 123 scenarios across 29 attack types and found that, without safeguards, 23.6% of attacks succeeded. In one example, a fake security email instructed Claude to delete emails, and it complied without seeking confirmation.

To address these risks, Anthropic has introduced several layers of protection. Users now have control over site-level permissions and must confirm high-risk actions such as purchases or email sending. The company has also implemented improved system prompts, blocked access to high-risk categories like financial services, adult content, and pirated platforms, and developed advanced classifiers to detect suspicious instructions and unusual data requests. Additionally, browser-specific protections have been added, successfully reducing targeted exploit success rates from 35.7% to 0%. Overall, Anthropic has lowered the prompt injection attack success rate from 23.6% to 11.2% and plans to further strengthen safeguards before making Claude for Chrome widely available.