Declaring your own Noun

A Noun file declares a record the template does not have. Leaseline declares a Lease Noun, and one file gives it an API, types and events.

What you buildCopy Anchor Link

You write nouns/Lease.mdx: a unit, a resident, an end date, a rent, a lifecycle and two Verbs, renew and notify. The body of the file is the Noun's documentation on every Interface.

StepsCopy Anchor Link

1. 1

   To declare the Noun, create its file at the project root:

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   ---
   extends: [Thing]
   properties:
     unit: string
     resident?: Contact
     endsOn: date
     rent?: money
     status: active | renewing | renewed | ended
   verbs:
     renew: { months: integer, increase?: number }
     notify: {}
   ---
   A Lease is one resident's agreement on one unit, from signing to renewal.

   A name ending in ? is optional. status holds the states, and only a Verb or an Event moves it.

2. 2

   To read what the save compiled, print the Verb's schema:

   $ npx startup-builder schema Lease.renew

3. 3

   To read the generated types, open .sb/types/Lease.d.ts:

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   interface LeaseRenewInput {
     lease: SB.Id
     months: number
     increase?: number
   }

4. 4

   To try the Verb without storing anything, call it with --try:

   $ npx startup-builder do Lease.renew --json '{"lease":"lease_4loEed1JG4","months":12}' --try

ResultCopy Anchor Link

One file gave Lease create, get, list, update and delete, and the Verbs Lease.renew and Lease.notify. It also gave the Events Lease.created, Lease.renewed and Lease.notified, and typed SDK methods, CLI operations, MCP tools and OpenAPI paths. Checkpoint leaseline@ch02 (status planned) adds nouns/Lease.mdx.

Next stepsCopy Anchor Link

• What compiles: the published artifacts, and what one more Verb changes.
• Tutorial 3 says what renew does.
• Nouns: every key the file takes.