A2A / Agent2Agent Protocol vs MCP Apps
An independent, evidence-based trust comparison of A2A / Agent2Agent Protocol and MCP Apps, two Protocols & Tool Integration projects in the HVTracker registry. Scores come from public, checkable signals — supply-chain provenance, OSSF Scorecard, maintenance, and adoption — not popularity.
A2A / Agent2Agent Protocol leads on trust — 89.3/100 (Grade A) vs 73.4/100 (Grade B), a 15.9-point gap. Full breakdown below.
| Signal | A2A / Agent2Agent Protocolgoogle/A2A | MCP Appsmodelcontextprotocol/ext-apps |
|---|---|---|
| HVTrust score | 89.3 | 73.4 |
| Evidence grade | A | B |
| Coverage grade | A | B |
| Overall rank | #13 | #87 |
| Rank in Protocols & Tool Integration | #2 | #7 |
| GitHub stars | 25.2k | 2.7k |
| Last updated | today | 12d ago |
| Build provenance | Yes | Yes |
| OSSF Scorecard | 7.0 / 10 | — |
| License | Apache-2.0 | NOASSERTION |
| Downloads | 2.6M/wk | 1.6M/wk |
| Trust dimensions (points earned) | ||
| Safety / integrity / 25 | 21.2 | 12.5 |
| Identity & provenance / 18 | 18.0 | 18.0 |
| Transparency / 17 | 14.4 | 8.5 |
| Maintenance / 20 | 17.2 | 13.2 |
| Adoption / 20 | 19.1 | 16.5 |
| Runtime capability surface (full matrix) | ||
| MCP server | — | Implemented |
| External providers | — | — |
| Requires API keys | No | No |
| Plugin surface | plugins | marketplace |
| Provenance drift | Unknown | Match |
Open in the live compare tool →
A2A / Agent2Agent Protocol profile
MCP Apps profile
More Protocols & Tool Integration →
How to read this: HVTrust (0–100) weighs supply-chain signals (provenance, OSSF Scorecard, signed commits, open license) alongside real-world adoption, scaled by an evidence-confidence factor. Grade bands: A ≥ 80, B ≥ 65, C ≥ 50, D < 50. Signals refresh daily. Full methodology v4.2 →