Value tracing
A call’s context label says whether the agent had read anything untrusted. Value tracing goes further. For each argument of a tool call, it finds every place that value appeared earlier in the run. That tells you whether the IBAN in a payment came from your supplier records or from a web page.
How matching works
- Values are compared after normalizing case, spaces and URL form.
- The search covers everything the run has read, across all its agents. An IBAN from one agent’s web page is caught in another agent’s payment.
- A known value is also found inside a longer argument, such as an IBAN or a URL inside an email body.
What gets traced
| Kind of value | Traced |
|---|---|
| IBANs, email addresses, URLs and domains, file paths | Always |
| Values that look like ids | When they are at least 8 characters long, have no spaces and contain a digit |
| Words, phrases, dates and amounts | Not on their own. The call is still marked influenced when its context is untrusted |
URLs and emails also match by host and by main domain, so mail.acme.co.uk matches acme.co.uk. The Public Suffix List decides what the main domain is. Ids match only as whole words.
Model-generated values
A value found nowhere earlier in the run is model-generated: the model wrote it instead of copying it from something it read. Rules can treat a model-generated value as untrusted for sensitive fields, such as an IBAN.
Content that Quard never sees can’t be traced. Pages read by the model provider’s hosted web search are one example: values copied from them also show as model-generated.
Matching is exact after normalizing. Near matches and paraphrases are not found.
In the dashboard
- The step drawer lists each argument with First seen in and how it matched: exact, or inside a value.
- Approval requests show untrusted origins and model-generated under each argument.
- Search finds a traced value across all runs. Sensitive values are stored as keyed hashes, and the same value always gives the same hash in a project, so tracing and search still match them.