W2A Open Protocol for Agent Sensors: Real-Time Perception

W2A (World2Agent) is an open protocol for the perception side of the agent loop — entirely self-hostable, no SaaS, no telemetry, TypeScript SDK, Apache 2.0. It standardizes how local agents receive real-time sensor data, replacing the usual pile of one-off scripts and cron jobs that each emit different JSON shapes and break when you switch agent frameworks.

Why it matters

The author frames 2024–2025 as the era of teaching agents to understand context (RAG, long context, memory), and 2025–2026 as teaching them to act (MCP, skills, tools). W2A targets the third leg: teaching agents to perceive. Without all three, you get a very smart intern who needs to be told everything.

Design choices

The protocol has no routing or priority logic — a sensor just emits, and the consumer (your agent) decides what matters. This keeps sensors simple and reusable. The same signal can feed a Claude Code agent, a Slack bot, and a dashboard with zero changes.

Quick start with Claude Code

Install the world2agent plugin in an active Claude Code session:

/plugin marketplace add machinepulse-ai/world2agent-plugins
/plugin install world2agent@world2agent-plugins
/reload-plugins

Add a sensor — for example, Hacker News:

/world2agent:sensor-add @world2agent/sensor-hackernews

Restart Claude Code with the plugin channel loaded so sensor signals flow into your session:

claude --dangerously-load-development-channels plugin:world2agent@world2agent-plugins

Pair with any local agent runtime (Ollama + small orchestrator, LiteLLM, etc.). The author runs it with a local 70B model and uses the summary-only fast path, falling back to full raw data only when needed.

Writing your own sensor

You can write a custom sensor in ~50 lines using defineSensor + createSignal + a setInterval or webhook, then emit. A working Slack sensor is in the repo as a reference.