claimable-postgres

Claimable Postgres

Instant Postgres databases for local development, demos, prototyping, and test environments. No account required. Databases expire after 72 hours unless claimed to a Neon account.

Quick Start

curl -s -X POST "https://neon.new/api/v1/database" \
  -H "Content-Type: application/json" \
  -d '{"ref": "agent-skills"}'

Parse connection_string and claim_url from the JSON response. Write connection_string to the project's .env as DATABASE_URL.

For other methods (CLI, SDK, Vite plugin), see Which Method? below.

Which Method?

• REST API: Returns structured JSON. No runtime dependency beyond curl. Preferred when the agent needs predictable output and error handling.
• CLI (npx neon-new@latest --yes): Provisions and writes .env in one command. Convenient when Node.js is available and the user wants a simple setup.
• SDK (neon-new/sdk): Scripts or programmatic provisioning in Node.js.
• Vite plugin (vite-plugin-neon-new): Auto-provisions on vite dev if DATABASE_URL is missing. Use when the user has a Vite project.
• Browser: User cannot run CLI or API. Direct to https://neon.new.

REST API

Base URL: https://neon.new/api/v1

Create a database

curl -s -X POST "https://neon.new/api/v1/database" \
  -H "Content-Type: application/json" \
  -d '{"ref": "agent-skills"}'

The connection_string returned by the API is a pooled connection URL. For a direct (non-pooled) connection (e.g. Prisma migrations), remove -pooler from the hostname. The CLI writes both pooled and direct URLs automatically.

Response:

{
  "id": "019beb39-37fb-709d-87ac-7ad6198b89f7",
  "status": "UNCLAIMED",
  "neon_project_id": "gentle-scene-06438508",
  "connection_string": "postgresql://...",
  "claim_url": "https://neon.new/claim/019beb39-...",
  "expires_at": "2026-01-26T14:19:14.580Z",
  "created_at": "2026-01-23T14:19:14.580Z",
  "updated_at": "2026-01-23T14:19:14.580Z"
}

Check status

curl -s "https://neon.new/api/v1/database/{id}"

Returns the same response shape. Status transitions: UNCLAIMED -> CLAIMING -> CLAIMED. After the database is claimed, connection_string returns null.

Error responses

CLI

npx neon-new@latest --yes

Provisions a database and writes the connection string to .env in one step. Always use @latest and --yes (skips interactive prompts that would stall the agent).

Pre-run Check

Check if DATABASE_URL (or the chosen key) already exists in the target .env. The CLI exits without provisioning if it finds the key.

If the key exists, offer the user three options:

1. Remove or comment out the existing line, then rerun.
2. Use --env to write to a different file (e.g. --env .env.local).
3. Use --key to write under a different variable name.

Get confirmation before proceeding.

Options

Alternative package managers: yarn dlx neon-new@latest, pnpm dlx neon-new@latest, bunx neon-new@latest, deno run -A neon-new@latest.

Output

The CLI writes to the target .env:

DATABASE_URL=postgresql://...              # pooled (use for application queries)
DATABASE_URL_DIRECT=postgresql://...       # direct (use for migrations, e.g. Prisma)
PUBLIC_POSTGRES_CLAIM_URL=https://neon.new/claim/...

SDK

Use for scripts and programmatic provisioning flows.

import { instantPostgres } from "neon-new";

const { databaseUrl, databaseUrlDirect, claimUrl, claimExpiresAt } =
  await instantPostgres({
    referrer: "agent-skills",
    seed: { type: "sql-script", path: "./init.sql" },
  });

Returns databaseUrl (pooled), databaseUrlDirect (direct, for migrations), claimUrl, and claimExpiresAt (Date object). The referrer parameter is required.

Vite Plugin

For Vite projects, vite-plugin-neon-new auto-provisions a database on vite dev if DATABASE_URL is missing. Install with npm install -D vite-plugin-neon-new. See the Claimable Postgres docs for configuration.

Agent Workflow

API path

1. Confirm intent: If the request is ambiguous, confirm the user wants a temporary, no-signup database. Skip this if they explicitly asked for a quick or temporary database.
2. Provision: POST to https://neon.new/api/v1/database with {"ref": "agent-skills"}.
3. Parse response: Extract connection_string, claim_url, and expires_at from the JSON response.
4. Write .env: Write DATABASE_URL=<connection_string> to the project's .env (or the user's preferred file and key). Do not overwrite an existing key without confirmation.
5. Seed (if needed): If the user has a seed SQL file, run it against the new database:

   psql "$DATABASE_URL" -f seed.sql

1. Report: Tell the user where the connection string was written, which key was used, and share the claim URL. Remind them: the database works now; claim within 72 hours to keep it permanently.
2. Optional: Offer a quick connection test (e.g. SELECT 1).

CLI path

1. Check .env: Check the target .env for an existing DATABASE_URL (or chosen key). If present, do not run. Offer remove, --env, or --key and get confirmation.
2. Confirm intent: If the request is ambiguous, confirm the user wants a temporary, no-signup database. Skip this if they explicitly asked for a quick or temporary database.
3. Gather options: Use defaults unless context suggests otherwise (e.g., user mentions a custom env file, seed SQL, or logical replication).
4. Run: Execute with @latest --yes plus the confirmed options. Always use @latest to avoid stale cached versions. --yes skips interactive prompts that would stall the agent.

   npx neon-new@latest --yes --ref agent-skills --env .env.local --seed ./schema.sql

1. Verify: Confirm the connection string was written to the intended file.
2. Report: Tell the user where the connection string was written, which key was used, and that a claim URL is in the env file. Remind them: the database works now; claim within 72 hours to keep it permanently.
3. Optional: Offer a quick connection test (e.g. SELECT 1).

Output Checklist

Always report:

• Where the connection string was written (e.g. .env)
• Which variable key was used (DATABASE_URL or custom key)
• The claim URL (from .env or API response)
• That unclaimed databases are temporary (72 hours)

Claiming

Claiming is optional. The database works immediately without it. To optionally claim, the user opens the claim URL in a browser, where they sign in or create a Neon account to claim the database.

• API/SDK: Give the user the claim_url from the create response.
• CLI: npx neon-new@latest claim reads the claim URL from .env and opens the browser automatically.

Users cannot claim into Vercel-linked orgs; they must choose another Neon org.

Defaults and Limits

Region cannot be changed for claimable databases. Unclaimed databases have stricter quotas. Claiming resets limits to free plan defaults.

Auto-provisioning

If the agent needs a database to fulfill a task (e.g. "build me a todo app with a real database") and the user has not provided a connection string, provision one via the API and inform the user. Include the claim URL so they can keep it.

Safety and UX Notes

• Do not overwrite existing env vars. Check first, then use --env or --key (CLI) or skip writing (API) to avoid conflicts.
• Ask before running destructive seed SQL (DROP, TRUNCATE, mass DELETE).
• For production workloads, recommend standard Neon provisioning instead of temporary claimable databases.
• If users need long-term persistence, instruct them to open the claim URL right away.
• After writing credentials to an .env file, check that it's covered by .gitignore. If not, warn the user. Do not modify .gitignore without confirmation.