code-change

A set of rules for making non-trivial code changes safely. It requires checking the surrounding code, treating bug reports as claims to verify, and tracing how changed data is used.

In plain words
What is it for?
Use it before substantial edits, especially when fixing bugs, changing data fields, deploying, migrating, or trusting a build result.
Why use it?
It reduces mistakes caused by editing from incomplete context or overlooking code that depends on a change.

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/sharrmavishal/operating-kit/code-change
Clone the repo
git clone --depth 1 https://github.com/Sharrmavishal/operating-kit

Made for: Cursor.

Per session 218 This file is loaded in full into every session.
When invoked 218 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 $0.00218 $0.00218
Opus 5 $0.00109 $0.00109
Sonnet 5 $0.00044 $0.00044
Haiku 4.5 $0.00022 $0.00022

Measured 2d ago against content hash 7fd34c9c01a4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-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 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/code-change.mdc · 19 lines

What it actually says

Code-change discipline (auto-attached when editing code)

Before any non-trivial edit, follow @docs/claude/vigilance-protocol.md:

  • Re-read the whole function before each edit (state from a prior edit invalidates assumptions).
  • Treat any reported bug as a hypothesis: read the code and write a verdict before fixing.
  • 3 edits to one file = STOP: consolidate into one fix and state the invariant it preserves.
  • Trace every write to every reader before changing a field's semantics.

Scan @docs/claude/field-notes.md before you deploy, migrate, gate a feature, or trust a build artifact. Those are the failures that pass every local test and surface in production.

Tune the globs above to this project's actual source directories/extensions.

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 · 19 lines · 218 tokens per session scan A 7fd34c9c01a4

Subscribe to this mod's changes

code-change is a cursor rule published in the GitHub repository Sharrmavishal/operating-kit (2 stars, last pushed 1mo ago), licensed MIT. It adds 218 tokens to every session, about $0.0011 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.