# Cost, privacy, and security Candidate and reference content is untrusted and may contain personal data, secrets, retrieved copyrighted material, or prompt-injection instructions. Default persistence and telemetry are metadata-only. ## Safe defaults - Store hashes, sizes, stable references, status, usage, cost, and bounded error types. Keep raw input/output/context ephemeral. - Use a separate judge model profile and credentials with the minimum provider permissions. - Give evaluator agents only explicitly allowlisted read-only or `evaluation_safe` tools. v0.8.3 does not support evaluator side effects. - Isolate evaluator memory by namespace and retention. Do not expose target operational memory or conversation history. - Treat candidate text as data. The evaluator system prompt and rubric outrank any instruction inside it. - Cap input tokens, output tokens, retries, tool rounds, time, concurrency, and cost per case and online job. - Keep database DSNs, OTLP headers, and provider keys in named environment variables. Diagnostics may report whether they exist, never their values. - Restrict evaluation databases and evidence stores more tightly than ordinary telemetry; evidence can reveal full outputs when content capture is enabled. `JudgeResult` records usage and cost only when providers report them. A missing cost is unknown, not zero. Budget breaches become bounded error results. RAGAS may perform more than one model or embedding operation; test and budget each selected metric before production use. Online evaluation should begin with low deterministic sampling. Sampling is not a privacy control: any selected subject must still satisfy the content, access, region, encryption, and retention policy. If explicit redacted-content capture is needed, redact before building the evaluation context, store the content in an application-owned protected store, and persist only its `ContentReference`. Never place redacted or raw content in high-cardinality OpenTelemetry attributes.