netlify-database

Instructions for adding managed Postgres, a relational database, to Netlify applications. It covers migrations, database access from Netlify runtimes, Drizzle ORM, local development, preview branches, and moving an existing Postgres project.

In plain words
What is it for?
Use it when creating tables, running SQL from Functions or Edge Functions, setting up migrations, connecting Drizzle, or developing locally with Netlify.
Why use it?
It provides the expected package, file locations, connection handling, and current API so database setup does not rely on outdated instructions.

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/netlify/context-and-tools/netlify-database
Clone the repo
git clone --depth 1 https://github.com/netlify/context-and-tools
Per session 106 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 4,636 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 2 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 $0.00106 $0.04636
Opus 5 $0.00053 $0.02318
Sonnet 5 $0.00021 $0.00927
Haiku 4.5 $0.00011 $0.00464

Measured yesterday against content hash 12322745c9d2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade C, and why

netlify-database scanned grade C with 2 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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- system: agent-context/database/system.md — human-owned, merged by ctx-gen; edit system.md, not this section -->

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

`--prod`); if a preview also fails, report and stop. Never curl
cursor/rules/netlify-database.mdc · 389 lines

How it starts

The opening of the file, as written. The whole thing — 389 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Netlify Database

Zero-config managed Postgres. Install @netlify/database, write migrations under netlify/database/migrations/, deploy — Netlify provisions the DB and applies migrations automatically. Queryable from Functions, Edge Functions, Builds, and Agent Runners.

Modern client (reach for this)

import { getDatabase } from "@netlify/database";

const db = getDatabase();               // auto-selects connection for the runtime
const userId = 42;
const users = await db.sql`SELECT * FROM users WHERE id = ${userId}`;  // auto-parameterized

Own driver / ORM instead:

import { getConnectionString } from "@netlify/database";
const connectionString = getConnectionString();  // correct branch for this env

Legacy — do NOT use for new code: import { neon } from "@netlify/neon". Superseded by @netlify/database. Replace neon() calls with the Drizzle netlify-db adapter or a Postgres driver via getConnectionString(). The legacy env var NETLIFY_DATABASE_URL is replaced by NETLIFY_DB_URL.

Where things go

What Location
Migrations netlify/database/migrations/ (SQL files or subdirs with migration.sql)
Query code Functions (netlify/functions/), Edge Functions
Drizzle schema db/schema.ts (convention)
Drizzle client db/index.ts (convention)
Connection string NETLIFY_DB_URL env var, or getConnectionString()

Querying

getDatabase(options?) returns a client with sql and pool. options.connectionString overrides the auto-provisioned one; options.debug enables logging.

const db = getDatabase();
const active = await db.sql`SELECT * FROM users WHERE active = ${true}`;
await db.sql`INSERT INTO users (name, email) VALUES (${"Ada"}, ${"[email protected]"})`;
await db.sql`UPDATE users SET name = ${"Ada Lovelace"} WHERE id = ${1}`;
await db.sql`DELETE FROM users WHERE id = ${1}`;

// Type the rows
interface User { id: number; name: string; email: string; }
const typed = await db.sql<User>`SELECT * FROM users`;

// Stream
for await (const row of db.sql`SELECT * FROM users`.stream()) { /* ... */ }
for await (const chunk of db.sql`SELECT * FROM users`.chunked(100)) { /* ... */ }

Read the full file on GitHub · 389 lines

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 · 389 lines · 106 tokens per session scan C 12322745c9d2

Subscribe to this mod's changes

netlify-database is a cursor rule published in the GitHub repository netlify/context-and-tools (36 stars, last pushed 5d ago), licensed MIT. It adds 106 tokens to every session and 4,636 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it C with 2 findings (hidden instructions, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.