preserve-comments

A coding rule that requires existing comments to remain during refactoring, cleanup and optimisation. It gives special protection to comments explaining compliance, tickets, safety warnings, dates, legal notes and business logic.

In plain words
What is it for?
Use it whenever modifying existing code where comments may document why the code works a certain way or record requirements that must be retained.
Why use it?
It prevents useful context from being lost when code is changed, while allowing removal of comments that are wrong, duplicated or empty boilerplate.

Cursor rule

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/nedcodes-ok/cursorrules-collection/preserve-comments
Clone the repo
git clone --depth 1 https://github.com/nedcodes-ok/cursorrules-collection
Per session 284 This file is loaded in full into every session.
When invoked 284 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 $0.00284 $0.00284
Opus 5 $0.00142 $0.00142
Sonnet 5 $0.00057 $0.00057
Haiku 4.5 $0.00028 $0.00028

Measured 2d ago against content hash 2f3c5b8eb532, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

preserve-comments 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.

rules-mdc/code-quality/preserve-comments.mdc · 33 lines

What it actually says

Comment Preservation

Always preserve all existing code comments during refactoring, cleanup, optimization, and any other code modification.

Protected Comment Types

Comments containing any of the following must never be removed or modified:

  • Compliance references: SOC2, GDPR, HIPAA, PCI-DSS, ISO 27001
  • Ticket references: JIRA, Linear, GitHub Issues, Asana task IDs
  • Safety warnings: "do not modify", "breaks if changed", "required by", "deprecated"
  • Date-stamped context: migration timelines, deprecation dates, review dates
  • Business logic explanations: why something works a specific way, not just what it does
  • Legal or audit notes: regulatory requirements, legal review references

Structural Comments

Comments explaining code flow, step-by-step processes, or non-obvious behavior should also be preserved. If a comment explains why rather than what, it stays.

When Removing Comments Is Acceptable

Only remove comments that are:

  • Demonstrably wrong (contradicted by the code they describe)
  • Exact duplicates of another comment in the same file
  • Auto-generated boilerplate that adds no information (e.g., // default constructor)

When in doubt, keep the comment.

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 · 33 lines · 284 tokens per session scan A 2f3c5b8eb532

Subscribe to this mod's changes

preserve-comments is a cursor rule published in the GitHub repository nedcodes-ok/cursorrules-collection (37 stars, last pushed 6mo ago), licensed MIT. It adds 284 tokens to every session, about $0.0014 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.