safe-change

safe-change is a skill for Codex from cz1993/vibe-coding-repository-standard. It costs 54 tokens per session (372 once invoked), scanned A, original, Apache-2.0.

A disciplined workflow for making one limited software change, from tracing the existing code through implementation, testing, and independent review.

In plain words
What is it for?
Use it for a defined feature, bug fix, or refactor with clear scope and acceptance criteria.
Why use it?
It keeps feature, bug-fix, and refactoring work focused while preserving validation, security, error handling, and useful tests.

Skill for Codex

Written for Codex: agents/openai.yaml present. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it for a defined feature, bug fix, or refactor with clear scope and acceptance criteria.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/cz1993/vibe-coding-repository-standard/safe-change
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.

Any agent
npx skills add cz1993/vibe-coding-repository-standard --skill safe-change
Clone the repo
git clone --depth 1 https://github.com/cz1993/vibe-coding-repository-standard

Made for: Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for safe-change

README.md
[![agentmods](https://agentmods.dev/badge/skills/cz1993/vibe-coding-repository-standard/safe-change/github.svg)](https://agentmods.dev/skills/cz1993/vibe-coding-repository-standard/safe-change)
Your own site
<a href="https://agentmods.dev/skills/cz1993/vibe-coding-repository-standard/safe-change"><img src="https://agentmods.dev/badge/skills/cz1993/vibe-coding-repository-standard/safe-change/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for safe-change

Your own site · 80×15
<a href="https://agentmods.dev/skills/cz1993/vibe-coding-repository-standard/safe-change"><img src="https://agentmods.dev/badge/skills/cz1993/vibe-coding-repository-standard/safe-change.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 372 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00054 $0.00372
Opus 5 $0.00027 $0.00186
Sonnet 5 $0.00011 $0.00074
Haiku 4.5 $0.00005 $0.00037

Measured 10d ago against content hash ca48e631873e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

safe-change 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 10d 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.

standard/template/.agents/skills/safe-change/SKILL.md · 49 lines

What it actually says

Safe Change

Inputs

  • user outcome;
  • in-scope behavior/modules;
  • explicit non-goals;
  • acceptance criteria;
  • safety and environment restrictions;
  • Git action.

Method

  1. Trace the current entry point, callers, inputs, outputs, dependencies, and side effects.
  2. Locate existing code, configuration, tests, and platform facilities before adding anything.
  3. Define the smallest defensible change and test scenarios.
  4. Implement only the accepted scope.
  5. Prefer, in order:
    • existing repository behavior;
    • language/runtime standard facilities;
    • framework/platform features;
    • already-installed dependencies;
    • direct code;
    • a new abstraction or dependency only with current evidence.
  6. Never simplify away validation, security, privacy, data isolation, error handling, observability, accessibility, migration safety, recovery, or useful tests.
  7. Add tests at the smallest credible level and cover important boundaries with integration/contract/smoke evidence as applicable.
  8. Review the complete diff and remove unrelated changes.
  9. Prepare a test table showing scenario, input/setup, expected, actual, and evidence.
  10. Use an independent read-only reviewer for non-trivial changes; resolve and recheck blockers.

Output

Report in plain language:

  • what changed and why;
  • files changed;
  • behavior before/after;
  • tests and actual outcomes;
  • reviewer findings and resolutions;
  • unrun validation and residual risk;
  • commit/PR identifiers.

Do not expose internal scratchpads or agent transcripts.

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 10d ago First seen · 49 lines · 54 tokens per session scan A ca48e631873e

Subscribe to this mod's changes

safe-change is a skill published in the GitHub repository cz1993/vibe-coding-repository-standard (21 stars, last pushed 25d ago), licensed Apache-2.0. It adds 54 tokens to every session and 372 once invoked, about $0.0003 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 2026-08-30.

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