jsdoc-line-width

A formatting rule for wrapping JSDoc and block-comment prose at the line width used by the Biome formatter. JSDoc is documentation written next to code declarations.

In plain words
What is it for?
Use it when writing or editing long code comments, including bullet lists and tagged sections such as parameters or return values.
Why use it?
It keeps comments consistent with automatic formatting and avoids noisy diffs caused by arbitrary narrow line breaks.

Cursor rule for Codex

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/prisma/orm/jsdoc-line-width
Clone the repo
git clone --depth 1 https://github.com/prisma/orm

Made for: Codex.

Per session 37 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 499 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 $0.00037 $0.00499
Opus 5 $0.00018 $0.00249
Sonnet 5 $0.00007 $0.00100
Haiku 4.5 $0.00004 $0.00050

Measured 2d ago against content hash 65b822944bc3, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

jsdoc-line-width 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.agents/rules/jsdoc-line-width.mdc · 25 lines

What it actually says

JSDoc / block-comment prose — wrap at the biome line width

When adding or editing prose in /** ... */ or long // documentation:

  1. Wrap at biome's lineWidth — Wrap prose at the line width configured in biome.jsonc (formatter.lineWidth, currently 100). Source of truth: read biome.jsonc rather than hard-coding the number; if it changes, this rule changes with it.

  2. No fixed-column wraps below the biome width — Do not break mid-sentence to stay under ~72 or ~80 characters. Editors soft-wrap; arbitrary narrow wraps make diffs noisy and conflict-prone.

  3. Bullet lists and tagged blocks

    • Bullets (* / -): keep each bullet's prose on one line up to the biome width before wrapping; wrap continuation lines aligned with the bullet text.
    • Tagged blocks (@param, @returns, @example): follow normal JSDoc conventions; the same line-width rule applies to the sentence text.
  4. Orphaned blocks — A doc comment must document the declaration that immediately follows it (after optional blank lines only before import / file headers). Do not leave a standalone /** ... */ between imports and the next export with no attached symbol; merge into the relevant declaration's doc or delete redundancy.

  5. Markdown is exempt — Do not apply this rule to .md files (READMEs, ADRs, PR bodies, rulecards, and any other Markdown). Markdown prose stays on one continuous line per paragraph; see .agents/skills/markdown-no-artificial-line-wraps/SKILL.md.

  6. Rationale — Wrapping at the same width that the formatter uses keeps doc-comment prose visually consistent with surrounding code, avoids both "one giant line" and "narrow 1990s terminal" extremes, and produces stable diffs because the wrap width is anchored to the formatter rather than picked per-author.

Related: .agents/skills/markdown-no-artificial-line-wraps/SKILL.md (Markdown files).

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 · 25 lines · 37 tokens per session scan A 65b822944bc3

Subscribe to this mod's changes

jsdoc-line-width is a cursor rule published in the GitHub repository prisma/orm (47,579 stars, last pushed yesterday), licensed Apache-2.0. It adds 37 tokens to every session and 499 once invoked, about $0.0002 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.