The dawn of MCP is stateless, interactive, and agent-native
HelloMCP is a reference implementation for a web where the agent is the runtime, MCP is the connective tissue, and useful software can appear exactly where the conversation needs it.
The intelligence already exists
An MCP server does not need to become another assistant. The harness already has a capable model, conversation context, user preferences, and often a rich set of connectors. HelloMCP uses that model as its planner and asks it to pass only normalized records into a deterministic renderer.
This keeps the server's public tool surface compact. New visual modules can arrive without teaching every agent a new orchestration API.
Stateless protocol, durable product
The MCP endpoint uses Cloudflare's current stateless handler and the version 2 TypeScript server SDK. It does not turn protocol sessions into Durable Objects. Saved decks are ordinary product data, stored behind a separate workspace-scoped Durable Object boundary.
Protocol state is not business state. Keeping the two separate makes the system easier to scale, reason about, and replace.
The App can talk back
An MCP App is not a screenshot. A setup button can message the host agent, an incident can ask for deeper read-only investigation, and a selected item can become model context. The interaction stays inside the user's harness, where connector permissions and confirmations already belong.
Portability starts with boring paths
The canonical package follows Agent Plugins 1.0: a root manifest, a root MCP configuration, and a skill at skills/hello/SKILL.md. Host-specific wrappers are compatibility layers, never the source of truth.