prefer-psl-in-design-docs

prefer-psl-in-design-docs is a cursor rule for Codex from prisma/prisma-next. It costs 437 tokens per session, scanned A, a copy of prefer-psl-in-design-docs, Apache-2.0.

A documentation rule for Prisma design documents that puts PSL examples first, with TypeScript examples only when they explain a TypeScript-specific feature.

In plain words
What is it for?
Use it when writing specifications, architecture documents, READMEs, or other design material that explains features available in both PSL and TypeScript.
Why use it?
Many Prisma users start with schema language, so leading with PSL makes the documentation easier to follow. It avoids repeating equivalent examples unnecessarily.

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/prisma-next/prefer-psl-in-design-docs
Clone the repo
git clone --depth 1 https://github.com/prisma/prisma-next

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 prefer-psl-in-design-docs

README.md
[![agentmods](https://agentmods.dev/badge/rules/prisma/prisma-next/prefer-psl-in-design-docs.svg)](https://agentmods.dev/rules/prisma/prisma-next/prefer-psl-in-design-docs)
Your own site
<a href="https://agentmods.dev/rules/prisma/prisma-next/prefer-psl-in-design-docs"><img src="https://agentmods.dev/badge/rules/prisma/prisma-next/prefer-psl-in-design-docs.svg" alt="Measured on agentmods" height="20"></a>
Per session 437 This file is loaded in full into every session.
When invoked 437 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00437 $0.00437
Opus 5 $0.00218 $0.00218
Sonnet 5 $0.00087 $0.00087
Haiku 4.5 $0.00044 $0.00044

Measured 4d ago against content hash 461179db4a01, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

prefer-psl-in-design-docs 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 4d 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

This is a copy

100% identical to prefer-psl-in-design-docs — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/rules/prefer-psl-in-design-docs.mdc · 22 lines

What it actually says

Prefer PSL examples in design docs

PSL is the default authoring surface (most users come from Prisma 1.x/2.x); the TS contract builder is secondary. Design docs (specs, ADRs, architecture docs, READMEs) should reflect that ordering.

  • Lead with PSL when illustrating a feature that exists in both surfaces.
  • Use TS only when the content is about the TS surface itself — model-handle brands, function-form predicates with ref(modelHandle), type-level inference, or any capability PSL's grammar cannot express.
  • A TS example that just restates the PSL one is noise — drop it; equivalence is implied.
  • Surface-neutral prose should avoid TS-only or PSL-only phrasing where the capability exists in both.

PSL code blocks must use the prisma language tag, never psl — only prisma is registered with the highlighters (GitHub, VSCode, docs site); psl renders as plain text. (The surface is colloquially "PSL" in prose, but the fence says prisma.)

Why it matters for design

The TS surface is by design a superset of PSL: it can express everything PSL can, plus TS-only capabilities (function-form using/withCheck, richer constraint overrides, closure-scoped helpers). It is never a subset. So PSL is where the difficult limitations bite — a static text parser constrains the grammar, and new design pressure surfaces in PSL first. Design a new authoring capability against PSL first; the TS surface follows by mirroring or extending. A design doc that only shows TS also fails to surface the harder design problem.

Runtime code (db.asUser(jwt), session.sql.from(...), middleware, config objects) has no PSL form and stays in TS — this rule covers authoring examples (contracts, models, fields, relations, policies), not runtime usage.

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. 4d ago First seen · 22 lines · 437 tokens per session scan A 461179db4a01

Subscribe to this mod's changes

prefer-psl-in-design-docs is a cursor rule published in the GitHub repository prisma/prisma-next (419 stars, last pushed 10d ago), licensed Apache-2.0. It adds 437 tokens to every session, about $0.0022 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to prefer-psl-in-design-docs, differing in 0 lines, and is treated as a copy.