Privacy and ZDR

Inference requests have Zero Data Retention (ZDR) by default, including chat completions.

ZDR is the default for Tuna's products. The exceptions are products that need to store data to work. Batch completions (not yet implemented), for example, need to keep requests until the batch runs. Those exceptions will be described on the product's docs page.

Zero Data Retention (ZDR) For All

All users are eligible, without a separate request or an enterprise plan.

Tuna does not store the content of your requests. Prompts and model replies are held only in volatile memory while they are processed, and the text isn't used to train models.

Tuna only keeps what it needs to bill you: which organization and key made a request, which model it used, when it ran, and its token counts. None of that includes the model inputs or outputs (text, image, video, audio, etc.).

KV Cache

When a model reads a prompt, it builds a KV cache: its internal state after reading that text. If the next request starts with the same text, such as the same system prompt, the model can reuse the cache instead of reading it all again. This makes responses faster and is why cached input costs less.

The KV cache is held in volatile memory. Depending on how a model is configured, it may use LMCache, an open-source KV cache layer for vLLM, and it may use LMCache to offload the KV cache to SSD storage.

When a model uses LMCache with KV cache SSD offload, Tuna always configures LMCache's encryption this way:

• Cache data is encrypted with AES-256 before it is written to the SSD.
• The key is generated at random when the cache server starts and is kept only in memory. It is never written to the SSD or to any other storage.
• The SSD's filesystem is also encrypted at rest.

As a result, the SSD alone cannot be used to read the cache, and the cache cannot be read after a restart. According to expert cryptographers, AES-256 is quantum safe for use in a post-quantum world. See NIST's assessment of AES and quantum computing.

For more on why this approach to KV caching is zero data retention (ZDR), see OpenRouter's post, Is Implicit Caching Prompt Retention?.

US Regional Routing

See US Regional Routing for the tuna-us/ location guarantee for GPU inference and KV caches. The page also covers edge processing and internet transit.

Privacy Policy and Terms of Service

These docs are for informational purposes only. Tuna's Privacy Policy and Terms of Service take precedence over these docs if there is a conflict.