goodvibes

A set of software-engineering rules for making small, deliberate code changes and handling failures clearly.

In plain words
What is it for?
Guiding implementation decisions, checking assumptions, keeping changes narrow, validating inputs, and writing actionable errors.
Why use it?
It reduces unnecessary code, limits unrelated edits, and calls attention to security risks such as injection attacks and leaked secrets.

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/jgiox/goodvibes/goodvibes
Clone the repo
git clone --depth 1 https://github.com/jgiox/goodvibes

Made for: Cursor.

Per session 242 This file is loaded in full into every session.
When invoked 242 The same file — it is already loaded in full.
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 $0.00242 $0.00242
Opus 5 $0.00121 $0.00121
Sonnet 5 $0.00048 $0.00048
Haiku 4.5 $0.00024 $0.00024

Measured 2d ago against content hash 2f7fa9d97e40, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

goodvibes 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 2d ago.

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/goodvibes.mdc · 29 lines

What it actually says

Engineering Rules — goodvibes

Think before coding

State assumptions explicitly before implementing. Stop if an assumption is security-sensitive, schema-sensitive, or has multiple materially different interpretations.

Simplicity first

Stop at the first rung that holds:

  1. Does this need to exist at all? Speculative need → skip it. (YAGNI)
  2. Already in this codebase? Reuse it.
  3. Stdlib does it? Use it.
  4. Native platform feature covers it? Use it.
  5. Already-installed dependency solves it? Use it.
  6. Can it be one line? One line.
  7. Only then: the minimum code that works.

Surgical changes

Keep diffs narrow. No opportunistic reformats. No renames unless required. Only remove what your change made unused.

Fail loud

No empty catch blocks. No silent retries. No returning fake success on real failure. Error messages must be actionable.

Security

Validate input at the boundary. Keep secrets out of code and logs. Flag immediately: SQL injection, XSS, command injection, path traversal, broken auth, leaked secrets.

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. 2d ago First seen · 29 lines · 242 tokens per session scan A 2f7fa9d97e40

Subscribe to this mod's changes

goodvibes is a cursor rule published in the GitHub repository jgiox/goodvibes (4 stars, last pushed 7d ago), licensed Apache-2.0. It adds 242 tokens to every session, about $0.0012 per session on Opus 5. 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 2026-08-31.