Artifacts

The Artifacts section declares the expected output format of the playbook’s final result. This metadata helps implementations render, download, or route the output appropriately.

Section Heading

## ARTIFACTS

Also recognized: ## OUTPUT (case-insensitive).

Type Declaration

The artifact type is declared with a type: line:

## ARTIFACTS

type: markdown

Regex

(?i)^type:\s*(\S+)$

Type matching is case-insensitive.

Dynamic Type

The artifact type supports {{variable}} interpolation, resolved at execution time:

## ARTIFACTS

type: {{output_format}}

The variable must be a declared input or a prior @output capture. The resolved value must be one of the valid types listed below.

Valid Types

Type	Description	Typical Use
`markdown`	Formatted text with headings, lists, code blocks	Reports, analyses, documentation
`json`	Structured JSON data	Data pipelines, API responses, configurations
`mermaid`	Mermaid diagram syntax	Flowcharts, sequence diagrams, architecture diagrams
`chartjs`	Chart.js configuration object	Data visualizations, dashboards
`html_css`	HTML with embedded or linked CSS	Rich formatted output, email templates
`javascript`	JavaScript code	Generated scripts, automation code
`typescript`	TypeScript code	Generated typed code

Unrecognized types produce a warning listing all valid types.

Behavior

The artifact type is metadata only — it does not change how steps execute. It informs the implementation about how to handle the final output:

Rendering: A mermaid artifact could be rendered as a diagram; markdown as formatted HTML
Download: The type suggests an appropriate file extension (.md, .json, .html, etc.)
Validation: Implementations may validate that the final step output conforms to the declared type
Routing: Output delivery systems can format payloads based on the artifact type
Dynamic resolution: If the type contains {{variable}}, it is resolved at execution time from inputs or named outputs

Default

If no ## ARTIFACTS section is present, implementations should treat the output as untyped text. The recommended default rendering is plain text or markdown.

Examples

Markdown Report

## ARTIFACTS

type: markdown

JSON Data Pipeline

## ARTIFACTS

type: json

Diagram Generation

## ARTIFACTS

type: mermaid

Dynamic Format Selection

## INPUTS

- `output_format` (enum: markdown, json, html_css): Desired format

## STEP 1: Generate

Create the report content.

## ARTIFACTS

type: {{output_format}}

Future Considerations

Multiple artifacts: A playbook could declare multiple output artifacts from different steps
Custom types: Allow implementation-specific artifact types beyond the standard set
Schema validation: For json artifacts, an optional JSON Schema could validate output structure