A2A / Agent2Agent Protocol vs mcpc
A2A / Agent2Agent Protocol leads on trust: 89.7/100 (Grade A) against 83.4/100 (Grade A), a 6.3-point gap. A2A / Agent2Agent Protocol leads on supply-chain integrity and adoption, and rests on broader evidence; mcpc leads on maintenance.
Agent2Agent (A2A) is an open protocol enabling communication and interoperability between opaque agentic applications.
Choose A2A / Agent2Agent Protocol if supply-chain integrity and adoption matter most.
- +7.1Adoption: 2.6M weekly downloads against 4k
- +3.3Safety / Integrity: 100% of recent commits signed, against 95%
- +2.1Transparency: OSSF Scorecard 7.0 against 4.5
- A vs BEvidence coverage: 4 of 5 independent signal types, against 3
The most compatible MCP CLI client. Supports: tools, resources, prompts, completions, async tasks, skills, stdio and Streamable HTTP (MCP 2026-07-28 and 2025-11-25). Persistent sessions, OAuth 2.1 with DCR, CIMD, client credentials, and ID-JAG, OS keychain, --json for code mode, grep across…
Choose mcpc if maintenance matters most.
- +0.6Maintenance: last push 1d ago, against 2d ago
Where they differ
1 dimension identical: Identity 18.0 · Full evidence table
An independent, evidence-based trust comparison of A2A / Agent2Agent Protocol and mcpc, 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.
Full evidence
| Signal | A2A / Agent2Agent Protocola2aproject/A2A | mcpcapify/mcpc |
|---|---|---|
| HVTrust score | 89.7 | 83.4 |
| Evidence grade | A | A |
| Coverage grade | A | B |
| Overall rank | #27 | #112 |
| Rank in Protocols & Tool Integration | #4 | #8 |
| GitHub stars | 26.2k | 1.0k |
| Last updated | 2d ago | 1d ago |
| Build provenance | Yes | Yes |
| OSSF Scorecard | 7.0 / 10 | 4.5 / 10 |
| License | Apache-2.0 | Apache-2.0 |
| Downloads | 2.6M/wk | 4k/wk |
| Trust dimensions (points earned) | ||
| Safety / integrity / 25 | 21.2 | 17.9 |
| Identity & provenance / 18 | 18.0 | 18.0 |
| Transparency / 17 | 14.4 | 12.3 |
| Maintenance / 20 | 17.5 | 18.1 |
| Adoption / 20 | 19.2 | 12.1 |
| Runtime capability surface (full matrix) | ||
| MCP server | — | Implemented |
| External providers | — | — |
| Requires API keys | No | Yes |
| Plugin surface | extensions | — |
| Provenance drift | Unknown | Match |
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 v4.4 →