Runtime

How It Works

1
Define tools
Create your tool functions in an entrypoint file (e.g., tools.ts)
2
Export functions
Export as a default object with keys matching your workflow tool IDs
3
Configure runtime
Set the entrypoint and permissions in your compozy.yaml
4
Execute tools
Use the configured runtime to run tools within workflows

Quick Example

compozy.yaml

name: my-project
version: "1.0.0"

runtime:
  type: bun
  entrypoint: "./tools.ts"
  permissions:
    - --allow-read
    - --allow-net

Configuration Properties

Property	Description	Default
`type`	JavaScript runtime (currently only `"bun"` is supported)	`bun`
`entrypoint`	Path to your tools file	`./tools.ts`
`permissions`	Security permissions for Bun runtime	`["--allow-read"]`

For detailed schema information and all available options, see the Runtime Schema.

The Entrypoint File

The entrypoint file (typically tools.ts) is where you define your custom tool functions. Each function receives parameters and returns data that can be used in your workflows.

tools.ts

// Define your tool functions
async function fetchData(params: { url: string }) {
  const response = await fetch(params.url);
  return await response.json();
}

// Export functions with keys matching workflow tool IDs
export default {
  fetch_data: fetchData,  // Key "fetch_data" must match tool ID in workflow
};

The exported object keys must exactly match the tool IDs defined in your workflow files. This is how Compozy maps workflow tool references to actual functions.

Learn more about tool development: