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Writing Contracts

Coming Soon

Detailed guide for writing behavioral contracts is under construction.

Basic Structure​

A behavioral contract is a YAML file that documents:

  1. Metadata - Package name, version range, maintainer
  2. Functions - Which functions are covered
  3. Preconditions - Requirements before calling
  4. Postconditions - What happens after (errors, returns)
  5. Edge Cases - Known gotchas

Example Template​

package: example-package
semver: ">=1.0.0 <2.0.0"
contract_version: "1.0.0"
maintainer: "your-github-username"
last_verified: "2026-02-27"
status: draft

functions:
  - name: exampleFunction
    import_path: "example-package"
    description: "What this function does"

    postconditions:
      - id: error-case
        condition: "When error occurs"
        throws: "ErrorType"
        required_handling: "How to handle it"
        source: "https://package-docs.com"
        severity: error

More Coming Soon​

We're working on a comprehensive guide. In the meantime:

  • See Schema Reference
  • Browse existing contracts in the corpus
  • Ask questions in GitHub Discussions