contract-default-values

A set of rules for preserving database column default values when a schema contract is emitted. A schema contract is a machine-readable description of database structure, and emitted output is generated from source definitions.

In plain words
What is it for?
Use it when adding or checking column defaults, including function defaults such as autoincrement() or now(). Re-emit the contract, verify the JSON payload, and use the metadata field when tooling needs the default.
Why use it?
It prevents defaults from being lost or hidden incorrectly during generation. Human-readable tree output stays concise, while JSON and programmatic data retain the complete default information.

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/contract-default-values
Clone the repo
git clone --depth 1 https://github.com/prisma/prisma-next

Made for: Codex.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 203 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00000 $0.00203
Opus 5 $0.00000 $0.00102
Sonnet 5 $0.00000 $0.00041
Haiku 4.5 $0.00000 $0.00020

Measured yesterday against content hash f35e11dc5934, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

contract-default-values 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 yesterday.

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 contract-default-values — 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/contract-default-values.mdc · 23 lines

What it actually says

Contract Default Values

Key points

  • When adding column defaults, re-emit the contract and verify the emitted JSON includes the full default payload.
  • Add the corresponding defaults.* capability when using function defaults like autoincrement() or now().

CLI output: tree vs JSON

Column defaults are handled differently depending on output format:

  • Tree output (db introspect): Labels show only type and nullability, e.g. id: int4 (not nullable). Defaults are omitted from labels to keep tree output concise.
  • JSON output (db introspect --json): Full default information is preserved in the schema IR.
  • Programmatic access: Defaults are always available in SchemaTreeNode.meta.default for tooling that needs them.

This separation keeps human-readable tree output clean while preserving full data for automation.

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. yesterday First seen · 23 lines · 0 tokens per session scan A f35e11dc5934

Subscribe to this mod's changes

contract-default-values is a cursor rule published in the GitHub repository prisma/prisma-next (421 stars, last pushed 7d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 203 tokens. A static security scan graded it A with 0 findings. It is 100% identical to contract-default-values, differing in 0 lines, and is treated as a copy.