Registry › Compare › A2A / Agent2Agent Protocol vs Composio

A2A / Agent2Agent Protocol vs Composio

A2A / Agent2Agent Protocol leads on trust: 89.9/100 (Grade A) against 73.5/100 (Grade B), a 16.4-point gap. A2A / Agent2Agent Protocol leads on supply-chain integrity and provenance; Composio leads on maintenance.

A A2A / Agent2Agent Protocol 89.9

Agent2Agent (A2A) is an open protocol enabling communication and interoperability between opaque agentic applications.

a2aproject/A2A · #23 overall · #4 Protocols & Tool Integration · coverage A (4/5)

Choose A2A / Agent2Agent Protocol if supply-chain integrity and provenance matter most.

+10.3Safety / Integrity: 100% of recent commits signed, against 51%
+7.2Identity / Provenance: package provenance attested, against none
+2.3Adoption: 2.7M weekly downloads against 37.9k

B Composio 73.5

Composio powers 1000+ toolkits, tool search, context management, authentication, and a sandboxed workbench to help you build AI agents that turn intent into action.

composiohq/composio · #282 overall · #14 Protocols & Tool Integration · coverage A (4/5)

Choose Composio if maintenance matters most.

+2.3Maintenance

Where they differ

21.2

Safety / IntegrityA2A / Agent2Agent Protocol +10.3

10.9

18.0

Identity / ProvenanceA2A / Agent2Agent Protocol +7.2

10.8

14.4

TransparencyA2A / Agent2Agent Protocol +0.2

14.2

17.7

MaintenanceComposio +2.3

20.0

19.2

AdoptionA2A / Agent2Agent Protocol +2.3

16.9

-0.6

Runtime calibrationComposio +1.3

+0.7

Full evidence table

An independent, evidence-based trust comparison of A2A / Agent2Agent Protocol and Composio, 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	Composiocomposiohq/composio
HVTrust score	89.9	73.5
Evidence grade	A	B
Coverage grade	A	A
Overall rank	#23	#282
Rank in Protocols & Tool Integration	#4	#14
GitHub stars	26.2k	30.7k
Last updated	today	today
Build provenance	Yes	No
OSSF Scorecard	7.0 / 10	6.7 / 10
License	Apache-2.0	MIT
Downloads	2.7M/wk	38k/wk
Trust dimensions (points earned)
Safety / integrity / 25	21.2	10.9
Identity & provenance / 18	18.0	10.8
Transparency / 17	14.4	14.2
Maintenance / 20	17.7	20.0
Adoption / 20	19.2	16.9
Runtime capability surface (full matrix)
MCP server	—	Declared
External providers	—	1 — OpenAI
Requires API keys	No	Yes
Plugin surface	extensions	plugins
Provenance drift	Unknown	Partial

Open in the live compare tool → A2A / Agent2Agent Protocol profile Composio 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 v4.4 →