R14.3: Token expiration bounding

Short answer: Short-lived access tokens paired with rotating refresh tokens. A long-lived token that leaks stays useful for months.

Group: Auth and sessions. Status: stable. Generated from the rule definitions; do not edit by hand.

Playground: https://brevio.pro/tools/agent-guard-playground?rule=R14.3

What it catches

Token expiration bounding: short-lived access tokens paired with rotating refresh tokens.

Why

A long-lived token that leaks stays useful for months.

A bad example

sign(payload, key, { expiresIn: '365d' })

A good example

sign(payload, key, { expiresIn: '15m' })  // plus a rotating refresh token

How it is checked

Nothing yet. No scanner and no slice card checks it: it is a standing rule for authors and reviewers.

How to silence it

A person can silence one finding with brevio-core: ignore R14.3 -- reason on the line or the line above. Without the reason it does not count. An agent cannot silence it: the agent hook and the MCP tools never honour the comment, and a pull request that adds one is reported until a reviewer allows it. Fixing the code is still the better answer.

To change what the rule flags, edit its definition in dev_rules.py or code_rules/__init__.py. That is a code change and is reviewed like one.

R14.4 CSRF token validation
R14.5 No credentials in URLs
R14.6 Strict redirect URL allowlist
R14.7 Brute-force throttle
Every rule