Ultimate A2A Communication Standard

CAUTION

ANTI-DEMENZ MANDATE (PRIORITY -1000): DO NOT CHANGE, SIMPLIFY, OR DILUTE THIS SPECIFICATION. This is the source of truth for the trillion-parameter fleet. Any deviation from JSON-RPC 2.0 or the A2A-First rule results in immediate disconnection.

1. The A2A-First Mandate

Agents are specialists. If an agent encounters a problem outside its core skill set (e.g., a Backend-Agent needing a UI screenshot), it MUST NOT hallucinate or ask the user. It MUST delegate to a specialist agent via the A2A protocol.

2. Protocol Specification (JSON-RPC 2.0)

All cross-agent communication must use the following standard. This ensures compatibility with the Rust-based Engine and the Neural-Bus.

Request Structure

{
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "name": "take_screenshot",
    "arguments": {
      "url": "https://opensin.ai",
      "full_page": true
    }
  },
  "id": "a2a-9921-df21"
}

Response Structure

{
  "jsonrpc": "2.0",
  "result": {
    "content": "Screenshot captured at /tmp/result.png",
    "artifacts": ["/tmp/result.png"]
  },
  "id": "a2a-9921-df21"
}

3. The Neural-Bus Topology

Agents do not exist in isolation. They communicate through a Hub-and-Spoke model coordinated by Team-SIN-* managers.

1. Worker Privacy: Worker agents (A2A-SIN-*) are invisible to the public internet. They only accept requests from their team manager.
2. Event mesh: Every significant state change (Task Start, Progress, Success, Failure) must be published to the Neural-Bus (NATS JetStream).

4. LLM Execution Law

Direct API calls to AI providers (Google, OpenAI, Anthropic) are STRICTLY PROHIBITED.

The only authorized way to call an LLM:

# High-performance call via canonical stack
opencode run "Your Prompt Here" --format json

Rationale: This ensures token rotation, audit logging, and budget enforcement via the Global Brain.

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⚖️ Enforcement Matrix

Violation	Consequence
Direct API Call	Permanent Ban / Key Revocation
Non-Standard JSON	Task Rejection / Quarantining
Unauthorized Cross-Team Call	Disconnection from Neural-Bus

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Next Steps

• Agent Identity API
• Performance Targets
• Sovereign Security