type-extraction-from-contract

type-extraction-from-contract is a cursor rule for Codex from prisma/orm. It costs 0 tokens per session (497 once invoked), scanned A, original, Apache-2.0.

A TypeScript pattern for extracting codec and operation types from database contract definitions. It supports both generated declaration files and contracts built directly in code.

In plain words
What is it for?
It helps connect contract definitions to the types used for data conversion and database operations.
Why use it?
It prevents type information from being lost or threaded through the wrong type layer when working with contracts.

Cursor rule for Codex

About the project

Prisma ORM is a Node.js and TypeScript database toolkit that lets applications work with databases through a programming interface instead of writing every query directly in SQL. Developers use it with databases including PostgreSQL, MySQL, MariaDB, SQL Server, SQLite, MongoDB, and CockroachDB. The catalogue add-ons provide agent rules, skills, hooks, agents, and other workflows for using Prisma.

prisma/orm · 47,601 stars · on GitHub

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/type-extraction-from-contract
Clone the repo
git clone --depth 1 https://github.com/prisma/orm

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 type-extraction-from-contract

README.md
[![agentmods](https://agentmods.dev/badge/rules/prisma/orm/type-extraction-from-contract.svg)](https://agentmods.dev/rules/prisma/orm/type-extraction-from-contract)
Your own site
<a href="https://agentmods.dev/rules/prisma/orm/type-extraction-from-contract"><img src="https://agentmods.dev/badge/rules/prisma/orm/type-extraction-from-contract.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 497 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 $0.00000 $0.00497
Opus 5 $0.00000 $0.00249
Sonnet 5 $0.00000 $0.00099
Haiku 4.5 $0.00000 $0.00050

Measured yesterday against content hash 4155fb530d3a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

type-extraction-from-contract 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

Copies of this mod

1 near-identical copy found in the catalogue:

.agents/rules/type-extraction-from-contract.mdc · 50 lines

What it actually says

Type Extraction from Contract

Pattern

CodecTypes and OperationTypes are carried via TypeMaps (type-only, not runtime keys).

  • Emitted workflow: contract.d.ts exports Contract and TypeMaps separately. Use CodecTypesOf<TypeMaps> and OperationTypesOf<TypeMaps> for explicit threading.
  • No-emit workflow: defineContract().build() returns ContractWithTypeMaps<Contract, TypeMaps>. Use ExtractCodecTypes / ExtractOperationTypes which extract from the phantom key.
// Emitted: import TypeMaps, use CodecTypesOf<TypeMaps>
import type { Contract, TypeMaps } from './contract';
type CodecTypes = CodecTypesOf<TypeMaps>;

// No-emit: ExtractCodecTypes works with ContractWithTypeMaps
type CodecTypes = ExtractCodecTypes<typeof contract>;

Helper Types

  • CodecTypesOf<TTypeMaps>: Extracts codecTypes from TypeMaps
  • OperationTypesOf<TTypeMaps>: Extracts operationTypes from TypeMaps
  • ExtractTypeMapsFromContract<T>: Extracts TypeMaps from contract (TypeMapsPhantomKey → extract, or never for emitted)
  • ExtractCodecTypes<T>: Extracts from ContractWithTypeMaps (no-emit), fallback Record<string, never>
  • ExtractOperationTypes<T>: Same for operation types

Lane APIs with Explicit TypeMaps

schema, sql, and orm accept optional TTypeMaps (defaults to ExtractTypeMapsFromContract<TContract>):

// No-emit: infers from ContractWithTypeMaps
const schemaHandle = schema<Contract>(context);

// Emitted: pass TypeMaps explicitly
const schemaHandle = schema<Contract, TypeMaps>(context);

Important

  • Codec/operation type maps do not exist at runtime on contract.mappings
  • Runtime contract values include only structural mappings (modelToTable, tableToModel, fieldToColumn, columnToField)
  • Generated Contract type (emitted) has no phantom keys; TypeMaps is a separate export
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 · 50 lines · 0 tokens per session scan A 4155fb530d3a

Subscribe to this mod's changes

type-extraction-from-contract is a cursor rule published in the GitHub repository prisma/orm (47,601 stars, last pushed 2d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 497 tokens. 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 2026-09-03.