> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://learning.postman.com/llms.txt. For full content including API reference and SDK examples, see https://learning.postman.com/llms-full.txt.

# Postman Collections schemas

Postman Collections are based on the open source *collection format*, which defines a structure for organizing API requests and modeling API workflows. The format is portable, machine and human readable, and can be used to generate client and server SDKs, documentation, and mock servers. The current version of Postman uses schema 3.0.0. Previous Postman schemas are available on the [Postman Schemas site](https://schema.postman.com/).

The collections schema 3.0.0 defines a collection with multiple YAML files organized on disk, so humans, AI agents, and automation tools can read, diff, review, and safely change collections in the same way as source code.

## File and directory structure

Any folder can serve as a collection root, with requests stored as `*.request.yaml` files and supporting assets living in reserved `.resources/` directories. Each request has a sibling `<request-name>.resources` directory containing its examples and scripts subdirectories, while collection- and folder-level metadata lives in optional `definition.yaml` files.

## Naming and path rules

Collections schema version 3.0.0 enforces filename-safe naming rules with normalization guidance, case-insensitive uniqueness, and mandatory forward-slash paths. The .yml extension is accepted as a parser alias, but .yaml is required for authoring output, and explicit path-resolution rules keep request resources scoped within their canonical directory.

<Note>
  In Postman v12, Newman can run a Postman Collection exported to the 2.1.0 format, but it can't run 3.0 collections. To run 3.0 collections, use the Postman CLI instead of Newman. For more information, see 

  [Develop with Native Git](/docs/agent-mode/native-git#develop-with-native-git)

  .
</Note>

## Ordering and extensibility

Ordering and sorting are handled by numeric fractional indexes to sort folders, requests, and examples. Examples and scripts are the initial normative resource types, but new resource directories can be added under `<request-name>.resources` without breaking existing naming rules. A shared model with an explicit type field keeps the format protocol-independent and future-proof.