Redaction

Secret masking on captured content — prompt, response, tool I/O and error messages — before any of it reaches the report, the log or a plugin.

It is on by default. A file on disk, with no retention policy and no access control, is the worst place for a secret to surface by accident.

What the default catches

redactSecrets knows a set of well-known patterns:

• Bearer … authorization headers
• connection strings with a password
• OpenAI-style keys (sk-…)
• GitHub tokens (ghp_…)
• JWTs
• fields named like api_key, password

export const config: ThenaConfig = { redact: true }; // the default

Configuring it

type RedactConfig = false | ((field: string, value: string) => string);

Value	Effect
absent	redactSecrets, the known patterns
false	off — only if the report never leaves your machine
function	replaces the default entirely

The field argument tells you what is being masked ("prompt", "response", tool I/O, error), so a rule can apply to one kind of content and not others.

Adding patterns without losing the defaults

A function replaces the default rather than extending it. Compose explicitly:

import { redactSecrets } from "@thenajs/core";

const INTERNAL_ID = /\bACC-\d{8}\b/g;

export const config: ThenaConfig = {
  redact: (field, value) => redactSecrets(value).replace(INTERNAL_ID, "ACC-********"),
};

Forgetting to call redactSecrets inside your own function silently turns off everything it covered — the single most likely mistake on this page.

What it cannot do

Redaction is regex over text. It catches things with a recognisable shape.

It does not catch a customer's name, an address, a free-form note, an internal URL, or a secret with no distinguishing format. There is no regex for "personal data".

For runs over real personal data, the tool is not a better pattern — it is not writing the text at all:

await app.run({ prompt, report: { content: false } });

That keeps the tree, the durations and the telemetry, and drops every prompt, response and tool payload. You still get the shape of the run, the cost and the timings; you just cannot read what was said.

Where it applies

Sink	Redacted
report (HTML and JSON)	yes
log, including "verbose"	yes
plugin onEvent payloads	yes
the model's own context	no
run({ data })	not applicable — never captured

That third row matters for a plugin author: what reaches onEvent is already masked, so you cannot un-redact it, and you should not build a second masking layer on top.

The fourth is the important one: redaction protects what is recorded, not what is sent. A secret you put in a prompt still goes to the model. Keeping things away from the model is what run({ data }) is for.

Using it outside the framework

redactSecrets is exported and is a plain string => string:

import { redactSecrets } from "@thenajs/core";

logger.info(redactSecrets(someText));

Useful when your tool logs something itself, on a path the framework never sees.

Cost

Masking runs per captured field, on the recording path only. On a run with no report, log or plugin, nothing is captured and nothing is masked.

If you have a very hot path and have measured that this matters, false turns it off — but read the sentence at the top of this page again first.

Related

• ThenaConfig
• Security
• Report