It’s about to become more expensive for Claude Code subscribers to use Anthropic’s coding assistant with OpenClaw and other third-party tools.

According to a customer email shared on Hacker News, Anthropic said that starting at noon Pacific on April 4 (today), subscribers will “no longer be able to use your Claude subscription limits for third-party harnesses including OpenClaw.” Instead, they’ll need to pay for extra usage through “a pay-as-you-go option billed separately from your subscription.”

The company said that while it’s starting with OpenClaw today, the policy “applies to all third-party harnesses and will be rolled out to more shortly.”

Anthropic’s head of Claude Code Boris Cherny wrote on X that the company’s “subscriptions weren’t built for the usage patterns of these third-party tools” and that Anthropic is now trying “to be intentional in managing our growth to continue to serve our customers sustainably long-term.”

The announcement comes after OpenClaw creator Peter Steinberger said he was joining Anthropic rival OpenAI, with OpenClaw continuing as an open source project with support from OpenAI.

Steinberger posted that he and OpenClaw board member Dave Morin “tried to talk sense into Anthropic” but were only able to delay the increased pricing by a week.

“Funny how timings match up, first they copy some popular features into their closed harness, then they lock out open source,” Steinberger said.

Cherny, however, insisted that Claude Code team members are “big fans of open source” and that he himself “just put up a few [pull requests] to improve prompt cache efficiency for OpenClaw specifically.”

“This is more about engineering constraints,” he said, adding that Anthropic is still offering full refunds for subscribers. “We know not everyone realized this isn’t something we support, and this is an attempt to make it clear and explicit.”

Meanwhile, OpenAI recently shut down its Sora app and video generation models, reportedly to free up computing resources and as part of a broader effort to refocus on winning over the software engineers and enterprises that are increasingly relying on products like Claude Code.