TypeScript

npm install agent-first-data

import { outputJson, outputPlain } from "agent-first-data";

const value = {
  code: "ok",
  result: {
    api_key_secret: "sk-123",
    latency_ms: 1280,
    db_url: "postgres://user:p@ss@db/app?token_secret=abc",
  },
};

console.log(outputJson(value));
console.log(outputPlain(value));

Useful names use TypeScript casing: outputJson, outputYaml, outputPlain, outputJsonWithOptions, redactedValue, redactSecretsInPlace, redactUrlSecrets, parseSize, normalizeUtcOffset, isValidRfc3339Date, isValidRfc3339Time, cliParseOutput, cliOutput, buildCliError, buildCliVersion, cliHandleVersionOrContinue, streamRedirectConfigFromRawArgs, and installStreamRedirectFromRawArgs.

Logging is available through initJson, initPlain, initYaml, span, and log.

import { initJson } from "agent-first-data";

initJson({ secretNames: ["authorization"] });

Behavior Notes

• Default redaction replaces every _secret or configured secret-name subtree with ***, including objects and arrays.
• _url fields scrub userinfo passwords and secret-named query parameters; surrounding whitespace is trimmed and internal whitespace redacts the whole field.
• YAML/plain quote and escape keys as well as values, sort by UTF-16 code unit order, and render nested objects in arrays as canonical JSON.
• Logging records use code: "log" plus a separate level field, so error-level logs are not terminal protocol errors.
• build_cli_error(message, hint?) returns {code:"error", error: message, hint?} only.
• Use cliHandleVersionOrContinue() before argument parsing so bare --version stays conventional and --version --output json|yaml|plain stays structured.
• Use installStreamRedirectFromRawArgs() before version/help handling if a CLI exposes --stdout-file or --stderr-file; stderr is redirected as native diagnostics, not JSON. Node fd-level redirection is process-lifetime because the standard library does not expose dup2 restoration.

Reference

• Full convention and API groups: docs/overview.md
• Formal cross-language contract: spec/agent-first-data.md
• Conformance fixtures: spec/fixtures
• Agent skill: skills/agent-first-data.md