version: "1.0.0" name: a2ui-create-feature-blueprint description: Provides instructions on how to create a new language-agnostic A2UI Feature Blueprint, ensuring consistency and ease of cross-language implementation.

A2UI Create Feature Blueprint Skill

This skill provides step-by-step instructions on how to design, format, and check in a new A2UI Feature Blueprint inside blueprints/features/ to specify behavioral or protocol changes before implementation.

1. Design Principles for Feature Blueprints

• Language Agnosticism: Keep the blueprint completely free of language-specific or framework-specific terminology.
• Generic Protocol Alignment: Reference specific messages, schemas, or JSON pointers as the primary mechanism for interaction.
• Portability: Design the feature so that it can be implemented cleanly across targeted SDK languages.

2. Step-by-Step Creation Recipe

Step 1: File Naming & Location

• Target Path: blueprints/features/<feature_name>.blueprint.md
• <feature_name> must be in snake_case (e.g. dynamic_theming.blueprint.md).
• Do NOT prefix filenames with a date.
• Initial Status: All newly created feature blueprints in blueprints/features/ start as optional (unmerged).

Step 2: Define YAML Frontmatter

Every feature blueprint must start with a YAML block containing:

---
feature_name: feature_name # Must match the filename's snake_case name exactly
module_blueprints:
  - a2ui_core # One or more valid module blueprint names affected
dependencies: [] # Optional list of prerequisite feature names
date_added: 2026-07-07 # Date initially authored (YYYY-MM-DD)
---

Step 3: Structure Content

Implement canonical Markdown sections:

1. # **[Feature Name] Feature Blueprint**
2. ## **Requirements**
3. ## **Detailed Description of Changes**
4. ## **Links**
5. ## **Test Cases & Conformance**
6. ## **Implementation Steps**

Step 4: Validate Blueprint

Run the blueprint validator script:

python3 blueprints/validate_blueprints.py