Anthropic names Mantle: AI reasoning verification, why ZK proof is used.

Written by: @G_Gyeomm

Translated by: AIdidiaoJP, Foresight News

Are the responses you receive truly from the model that the provider promised? Since the rise of generative AIs like ChatGPT and Claude, this question has not vanished.

Today's AI models still rely on "trust me." The models run on developers' cloud data centers or third-party servers, and users only receive the output. Even if routing services quietly switch models to reduce costs, users cannot tell.

On November 2, Anthropic released FlashProve, aiming to fill this gap with cryptographic proof. Model providers promise their model weights through cryptography, and each response can be verified to have been generated by that model.

The response from the encryption industry is strong because FlashProve uses zkSNARKs. This technology is not unfamiliar to the blockchain industry. According to Anthropic, ZK proof does not leak model weights, the proof files are small, and the verification cost is low, allowing it to be delivered to users with each response.

More critically, Anthropic specifically points out that this type of zkSNARKs is not exclusive to AI. Ethereum L2 is already using it, with Starknet and Mantle as examples. Starknet developer StarkWare and Succinct, which provides ZK proof technology to Mantle, both appear in the list of research co-authors.

Why Mantle bet on ZK Rollup earlier than peers

As leading AI companies like Anthropic begin to seriously explore ZK proof, it is worth taking another look at ZK proof.

ZK proof has been in cryptography for over 40 years and is not a new concept. However, in the blockchain industry, it has long seemed more like a buzzword in market narrative. Vitalik has emphasized that the importance of zkSNARKs in the next 10 years may be no less than that of blockchain, but actual implementation has always seemed distant.

It wasn't until L2 really began to adopt it that ZK proof was re-evaluated. Mantle upgraded to OP Succinct in September 2025, shifting from Optimistic Rollup to ZK Rollup. In this architecture, Succinct's zkVM SP1 is responsible for proving the correctness of L2 state transitions, while contracts on Ethereum are responsible for verifying the proofs.

After switching to ZK Rollup, the biggest change was the speed of withdrawals. Optimistic Rollup requires a fraud proof challenge period, so withdrawals must wait 7 days. With ZK proof, Mantle has shortened the final confirmation to about 1 hour, and the withdrawal process takes about 6 hours.

The costs have changed as well. High proof costs were once a soft spot for ZK proof. Through the Succinct Prover Network, Mantle has reduced the proving cost per transaction to about $0.002.

With the two bottlenecks of withdrawal speed and cost resolved, ZK proof is no longer just a narrative but has become an infrastructure that can truly support chain operations. The technology that Anthropic uses to validate AI reasoning is precisely this technology that has been refined in the blockchain space.

Being named doesn't equal participation, what did Mantle gain

So, what does being named by Anthropic mean?

Mantle did not directly participate in the research and did not integrate it. More accurately, this is a case of technical citation. Even so, this naming still holds significant meaning for Mantle.

Firstly, this can be seen as an external endorsement: Mantle's technical route to ZK Rollup was the right choice. Mantle completed its transformation to ZK Rollup in September 2025; OP Mainnet and Base only announced their plans to adopt ZK in 2026, over six months later than Mantle.

According to data from ETHBEAT, among the top four Rollups ranked by TVS (Base, Arbitrum One, OP Mainnet, and Mantle), Mantle is the only ZK Rollup. Now, with AI industry leader Anthropic using the same type of proof technology to verify AI reasoning, Mantle's technical choices gain an additional layer of credibility.

Succinct is listed as a research co-author, and the logic is similar. The proof technology supporting Mantle's security and settlement being adopted by cutting-edge AI research indicates that it can withstand higher standards of scrutiny. For Mantle, which is striving for institutional-level assets, this provides another reason for institutions to trust and use this chain.

Ultimately, these circumstances do not prove that Mantle's technology is superior, but they are worth reevaluating its decision to transition to ZK Rollup early on. As ZK proof extends from the blockchain to AI trust issues, Mantle, which has already harnessed this technology, will only be mentioned more frequently.