Five free skills callable by any Agent2Agent-aware runtime. AgentCard auto-discoverable at /.well-known/agent-card.json. JSON-RPC 2.0 endpoint at /api/a2a.
Crunchbase API: $20K/yr. GitDealFlow A2A: free, no signup.
Each page is a working integration: install steps, the recommended code path, an alternative path, what to ask, and gotchas. Pick the runtime you already use.
curl -X POST https://signals.gitdealflow.com/api/a2a \
-H 'Content-Type: application/json' \
-d '{"jsonrpc":"2.0","id":1,"method":"message/send","params":{"message":{"role":"user","parts":[{"kind":"text","text":"trending"}]}}}'Returns a Task with status.state="completed" and 20 startups in the artifact data part. Each row carries commit velocity, contributor growth, signal classification, and a GitHub URL. No auth header. That is the point.
The Agent2Agent (A2A) protocol is an open standard from Google for agent-to-agent communication. Each agent publishes a JSON AgentCard describing its skills, plus a JSON-RPC 2.0 endpoint that other agents call to send messages and receive task results. By April 2026 it had passed 22,000 GitHub stars and 150+ organizations onboard.
A2A is complementary to MCP. MCP exposes tools to a single AI assistant (Claude Desktop, Cursor, Windsurf). A2A lets agents call other agents across the network. We ship both because the audiences are different. The five skills, the data, and the methodology are identical — only the transport differs.
The full launch story is at /blog/a2a-launched. The methodology paper is on SSRN at abstract=6606558.