security

Required security rules for credentials, logs, untrusted text, file access, permissions, and shell commands. A sandbox is a restricted environment that limits what code can read or change.

In plain words
What is it for?
They cover secure credential storage, removal of secrets from logs, protection against prompt injection, permission checks for outside-sandbox writes, and blocking critical shell operations.
Why use it?
They help prevent API keys from being exposed, hostile instructions from being followed, and code from escaping its allowed workspace or running dangerous commands.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/hoangsonww/forge-agentic-coding-cli/security
Clone the repo
git clone --depth 1 https://github.com/hoangsonww/Forge-Agentic-Coding-CLI

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 226 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00226
Opus 5 $0.00000 $0.00113
Sonnet 5 $0.00000 $0.00045
Haiku 4.5 $0.00000 $0.00023

Measured yesterday against content hash 55d91f544fde, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

security scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/security.mdc · 24 lines

What it actually says

Security rules (non-negotiable)

  • Credentials live in the OS keychain (src/keychain/) or the encrypted fallback. Never in a config file at rest.
  • All log output routed through src/security/redact.ts. Do not console.log a config object that may contain an API key.
  • Prompt-injection defence uses fenced-data boundaries (src/security/injection.ts). Any new place that ingests untrusted content must be fenced.
  • Never add a code path that writes outside the sandbox without a matching permission gate. Never bypass permission prompts unless the user explicitly passed --skip-permissions or --allow-*.
  • Shell risk is classified in src/sandbox/shell.ts. The critical tier is hard-blocked — do not add exceptions.
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 24 lines · 0 tokens per session scan A 55d91f544fde

Subscribe to this mod's changes

security is a cursor rule published in the GitHub repository hoangsonww/Forge-Agentic-Coding-CLI (22 stars, last pushed 15d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 226 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.