# FlashProve

When a user queries a large model, nothing in the reply shows it came from the model the developer claims, so a routing service swapping in a cheaper model or an attacker tampering with the token stream goes unnoticed. Anthropic's open-source FlashProve attaches a zero-knowledge succinct argument (zkSNARK, a short certificate a verifier can check quickly without the weights) to inference. On 4-bit Llama 4 Maverick, a 400B-parameter mixture of experts, a single H100 generates proofs at about 110 tokens per second, roughly 19 MB per 1,024-token request, at about 70 to 95 times the GPU time vLLM needs to run the model itself.

When a user queries a large model, nothing in the reply shows it came from the model the developer claims, so a routing service swapping in a cheaper model or an attacker tampering with the token stream goes unnoticed. Anthropic's open-source FlashProve attaches a zero-knowledge succinct argument (zkSNARK, a short certificate a verifier can check quickly without the weights) to inference. On 4-bit Llama 4 Maverick, a 400B-parameter mixture of experts, a single H100 generates proofs at about 110 tokens per second, roughly 19 MB per 1,024-token request, at about 70 to 95 times the GPU time vLLM needs to run the model itself.