# Security Content-validation rules that catch payloads and instructions invisible to human review: invisible/bidi unicode smuggling (ASCII smuggling, Trojan Source), agent directives hidden in HTML comments or Markdown link labels, and long high-entropy base64/hex blobs that can smuggle encoded payloads, plus unallowlisted dynamic-context commands in agent content. They complement `hooks-dangerous`, `claude-settings-dangerous`, and `content-embedded-secrets`, which cover the executable and credential sides of the same threat. | Rule ID | Description | Default Severity | Autofix | |---------|-------------|------------------|---------| | [`security-invisible-unicode`](security-invisible-unicode.md) | Detect invisible or reordering unicode characters (ASCII smuggling, Trojan Source) in agent context | error (auto) | - | | [`security-hidden-instructions`](security-hidden-instructions.md) | Detect agent directives hidden in HTML comments or Markdown link labels invisible to human review | warning (auto) | - | | [`security-encoded-payload`](security-encoded-payload.md) | Detect long high-entropy base64/hex blobs that can smuggle encoded payloads | warning (auto) | - | | [`security-dynamic-context`](security-dynamic-context.md) | Require an allowlist for dynamic context commands that execute shell code while loading agent context | warning (auto) | - |