Extending Kickstart

Kickstart is built on the harness + packs model. All domain knowledge lives in packs; the harness is domain-agnostic. Extension means authoring a new pack or contributing to an existing one.

Extension Points

What you want to add	Primitive	Where it lives
A new AI persona	Agent (.agent.md)	packages/pack-*/src/agents/
Domain knowledge for agents	Skill (SKILL.md)	packages/pack-*/src/skills/
A server-side function the LLM can call	Tool	packages/pack-*/src/tools/
A browser interaction (auth, consent, etc.)	UserAction	packages/pack-*/src/user-actions/
A new A2UI component type	Component	packages/pack-*/src/components/
A cross-cutting check	Guardrail	packages/pack-*/src/guardrails/
A new HTTP endpoint	Azure Function	packages/web/api/src/functions/
IDE tool exposure	MCP tool	packages/mcp-server/src/

Architecture Overview

packages/
├── harness/              ← Runtime: pack registry, Runner, SSE, session
│   └── src/runtime/      ← Skill resolver, guardrail engine, catalog
├── pack-core/            ← Base agents, skills, tools, components
├── pack-azure/           ← Azure domain
├── pack-aks-automatic/   ← AKS Automatic domain
├── pack-github/          ← GitHub domain
├── web/api/              ← Azure Functions HTTP layer
└── mcp-server/           ← MCP adapter

Where to Start

• New LLM capability (no browser interaction)? → Author a Tool in the relevant pack. One file, register in the pack's index, done.
• Browser popup / credential flow? → Author a UserAction. The harness handles pause/resume automatically.
• New AI persona? → Author an .agent.md file. Declare its allowed tools and handoff targets in frontmatter.
• Domain knowledge injection? → Author a SKILL.md file with an appliesTo glob targeting the relevant agents.
• New integration domain (e.g., a new cloud provider)? → Create a new pack that contributes agents + skills + tools + user actions together.
• New HTTP surface? → API Endpoints covers the Azure Functions v4 pattern with SSE streaming.
• IDE integration? → MCP Tools covers MCP tool authoring for VS Code Copilot and Claude Code.

If you add .agent.md or SKILL.md files, the build copies them into pack-scoped pack-assets/{pack}/{agents|skills}/ folders that the emitted server manifest resolves at runtime. All packs load those bundled assets from dist/functions/pack-assets/..., including pack-github even though its source markdown lives at the package root.

Design Principles

Packs are the unit of extensibility. A pack is a sealed bundle registered at startup. The harness is domain-agnostic — it does not know about Azure, AKS, GitHub, or any product domain.

First-party only. No plugin sandbox or dynamic loading — all packs are compiled into the monorepo. Everything registered is trusted code.

Tools have no side effects on their own. Agents call tools; tools return typed results. Browser interactions go through UserActions, which pause the runner and wait for a browser POST.

Skills are pure text. No code, no execution. If you need execution, write a tool.