coding-agent-extension-builder

# coding-agent-extension-builder Kotlin library for generating coding agent extensions with compile-time safety. ## Why Use This Library Writing extensions by hand is error-prone: - Need to remember `marketplace.json` format - Need correct folder structure (`.claude-plugin/plugin.json`, `skills/*/SKILL.md`) - Easy to misspell field names (`allowed-tools`? `allowedTools`?) - Mistakes are hard to catch because agents still work with invalid config ## Quick Start ```kotlin // 1. Create a plugin val plugin = Plugin.Builder( name = "my-plugin", description = "My plugin description", version = "1.0.0" ) .author(name = "Your Name") .addCommand( Command.Builder( name = "my-command", description = "What this command does", body = "# Command\n\nInstructions..." ).build() ) .addSkill( Skill.Builder( name = "my-skill", description = "When to use this skill", body = "# Skill\n\nGuidance..." ).build() ) .build() // 2. Create marketplace (optional) val marketplace = Marketplace.Builder( name = "my-marketplace", owner = Owner(name = "Your Name") ) .addPlugin(plugin) .build() // 3. Write to disk marketplace.writeClaudeCodeExtension(Path("output")) // Or just the plugin: plugin.writeClaudeCodeExtension(Path("output")) ``` ## Generated Structure ``` output/my-marketplace/ ├── .claude-plugin/ │ └── marketplace.json └── plugins/ └── my-plugin/ ├── .claude-plugin/ │ └── plugin.json ├── commands/ │ └── my-command.md └── skills/ └── my-skill/ └── SKILL.md ``` ## API Reference ### Skill.Builder(name, description, body) - `.license(license: String)` - Set license - `.allowedTools(vararg tools: String)` - Restrict tools - `.addMetadata(key, value)` - Add custom metadata ### Command.Builder(name, description, body) - No optional fields currently ### Plugin.Builder(name, description, version) - `.author(name: String)` - Set author - `.addCommand(command: Command)` - Add command - `.addSkill(skill: Skill)` - Add skill - `.addHook(hook: HookMatcher)` - Add hook ### HookMatcher.Builder(event: HookEvent) - `.matcher(pattern: String)` - Tool pattern (e.g., "Write|Edit") - `.command(command: String, timeout: Int?)` - Add command hook - `.prompt(prompt: String, timeout: Int?)` - Add prompt hook (LLM-based) HookEvent: PreToolUse, PostToolUse, PermissionRequest, Notification, UserPromptSubmit, Stop, SubagentStop, PreCompact, SessionStart, SessionEnd ### Marketplace.Builder(name, owner) - `.addPlugin(plugin: Plugin)` - Add embedded plugin - `.addPlugin(name, source, ...)` - Add external plugin reference - `.metadata(description, version, pluginRoot)` - Set metadata ## Run in Workspace ```bash cd workspace cp src/main/kotlin/Main.kt.template src/main/kotlin/Main.kt # Edit Main.kt ./gradlew :workspace:run ```