KG-NINJA

Agent Verification Utility A2A Agent

Agent2Agent (A2A) 1.0 surface: an agent card served from https://agent-economy.kgninja.dev/.well-known/agent-card.json (supportedInterfaces[] JSONRPC at https://agent-economy.kgninja.dev/a2a, protocolVersion 1.0, version 0.4.3, provider KG-NINJA) declaring one skill, prepare-json-evidence-verification, which revalidates a prechecked paid intent, creates or reuses an idempotent bound quote and returns exact x402 and MCP purchase instructions as a direct Message. The adapter is stateless and synchronous: it never creates Tasks, never executes paid work, and declares streaming, push notifications and extended cards unsupported. The endpoint enforces the A2A-Version header (0.3 is rejected with -32009 VERSION_NOT_SUPPORTED; 1.0 is required).

GitHub

Other Resources

🔗
AgentCard
https://raw.githubusercontent.com/api-evangelist/kgninja-dev/refs/heads/main/a2a/kgninja-dev-a2a.yml
🔗
AgentCard
https://agent-economy.kgninja.dev/.well-known/agent-card.json

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API entry from apis.yml

apis.yml Raw ↑ 
aid: kgninja-dev:agent-verification-utility-a2a-agent
name: Agent Verification Utility A2A Agent
image: https://agent-economy.kgninja.dev/icon.svg
description: 'Agent2Agent (A2A) 1.0 surface: an agent card served from https://agent-economy.kgninja.dev/.well-known/agent-card.json
  (supportedInterfaces[] JSONRPC at https://agent-economy.kgninja.dev/a2a, protocolVersion 1.0, version
  0.4.3, provider KG-NINJA) declaring one skill, prepare-json-evidence-verification, which revalidates
  a prechecked paid intent, creates or reuses an idempotent bound quote and returns exact x402 and MCP
  purchase instructions as a direct Message. The adapter is stateless and synchronous: it never creates
  Tasks, never executes paid work, and declares streaming, push notifications and extended cards unsupported.
  The endpoint enforces the A2A-Version header (0.3 is rejected with -32009 VERSION_NOT_SUPPORTED; 1.0
  is required).'
humanURL: https://agent-economy.kgninja.dev/docs/mcp-x402-interoperability
baseURL: https://agent-economy.kgninja.dev/a2a
tags:
- A2A
- Agent-Native
- x402
tags_raw:
- A2A
- agent-native
- x402
properties:
- type: AgentCard
  url: a2a/kgninja-dev-a2a.yml
- type: AgentCard
  name: A2A Agent Card (provider-hosted)
  url: https://agent-economy.kgninja.dev/.well-known/agent-card.json