updated 2026-08-25 11:32 UTC

A2A / Agent2Agent Protocol

a2aproject/A2A

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

Protocols & Tool Integration Shell Grade A Listed Apache-2.0
89.4/100
Rank #18 of 1308
Compare A2A / Agent2Agent Protocol

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Strong public trust posture, backed by multiple independent signals.

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Listing state
Listed
Evidence coverage
Grade A · 4/5 signals
Last push
2026-08-25 · 0d ago
Recent change
No recent signal change

Is A2A / Agent2Agent Protocol safe? A2A / Agent2Agent Protocol scores 89.4/100 (Grade A), ranked #18 of 1308 tracked open-source AI agent projects, on evidence coverage A (4 of 5 independent signal types). The public evidence: its packages ship with cryptographic provenance; OSSF Scorecard rates its supply-chain practices 7.0/10; 99% of recent commits are signed; last pushed 2026-08-25. Every point is earned from checkable signals — never paid placement. How scoring works →

Ranked neighbours in Protocols & Tool Integration

#1 MCP Inspector — 90.8 (A) → #3 FastMCP (TypeScript) — 86.3 (A) → #4 MCP Apps — 84.8 (A) → #5 CLI-Anything — 81.1 (A) →

Quick Trust Read

What Would Improve It
Improve transparency to lift the weakest part of the trust profile.
Maintainer Checklist
Keep signals current Trust posture is already in a healthy range. The main job is to keep provenance, maintenance, and public evidence fresh.
Compare with MCP Inspector Get email alerts for A2A / Agent2Agent Protocol View Protocols & Tool Integration Report missing data
83.8
Activity sub-score · out of 100
#2
In 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. Grade A reflects the trust score band: A ≥ 80, B ≥ 65, C ≥ 50, D < 50. Evidence coverage A is separate — it grades how many independent signal types back the score (4 of 5), so a high score on thin evidence stays visible. Full methodology →

Signals refreshed 2026-08-25 11:32 UTC · Repo last pushed today

Rank Trend

2026-08-11 2026-08-25

Activity & Reach

Stars
25.5k
Forks
2.6k
Last Push
2026-08-25
today
Commits (4 wk)
20
Downloads (7d)
2,615,893
pypi
HN mentions (30d)
0
Open Issues
183
Rank Change
▲1
was #19

Analysis

HVTrust Dimensions vs Protocols & Tool Integration

89.4 / 100 · 100.0% confidence

A2A / Agent2Agent Protocol Protocols & Tool Integration average (58 agents)

Safety / Integrity50% OSSF Scorecard · 30% provenance · 20% signed commits
21.2 / 25
12.7 above avg 8.5
Identity / Provenance60% listing status · 40% build provenance
18.0 / 18
6.3 above avg 11.7
Transparency50% declared license · 50% OSSF Scorecard
14.4 / 17
3.0 above avg 11.4
Maintenance60% last-push freshness · 40% commit activity
17.3 / 20
3.5 above avg 13.8
AdoptionLog-scaled stars · package downloads
19.1 / 20
8.8 above avg 10.3

Activity Inputs

83.8 / 100
StarsRepository reach
26.4 / 30
FreshnessLast push recency
25.0 / 25
ActivityRecent commits
16.5 / 25
CommunityFork signal
15.9 / 20

Supply Chain Trust

Package Provenance
Verified
pypi attestation
OSSF Scorecard
7.0 / 10
OpenSSF Scorecard · scanned Aug 25, 2026
Signed Commits
99%
of last 100 commits verified
Binary-Artifacts 10
Branch-Protection 8
CI-Tests 10
CII-Best-Practices 0
Code-Review 9
Contributors 10
Dangerous-Workflow 10
Dependency-Update-Tool 10
Fuzzing 0
License 10
Maintained 10
Packaging -1
Pinned-Dependencies 0
SAST 0
Security-Policy 9
Signed-Releases -1
Token-Permissions 0
Vulnerabilities 10

Is A2A / Agent2Agent Protocol safe?

Public supply-chain signals for A2A / Agent2Agent Protocol are strong: it has multiple independent trust indicators in place. This does not replace your own security review, but A2A / Agent2Agent Protocol carries less obvious unverified-evidence risk than projects with thin signals.
Does A2A / Agent2Agent Protocol publish package provenance?
Yes. A2A / Agent2Agent Protocol's package releases carry build provenance attestations, which cryptographically link the published package back to its source repository and CI workflow.
Does A2A / Agent2Agent Protocol have an OpenSSF Scorecard?
A2A / Agent2Agent Protocol has an OpenSSF Scorecard score of 7.0/10. The Scorecard checks for branch protection, signed releases, dependency updates, fuzzing, code review, and other supply-chain hygiene items. See the full check breakdown on this page.
Is A2A / Agent2Agent Protocol actively maintained?
Actively maintained. The repository was pushed to within the last 1 day(s).
What license does A2A / Agent2Agent Protocol use?
A2A / Agent2Agent Protocol ships under Apache-2.0. A declared, OSI-approved license is one of the transparency signals HVTrust scores.
Are A2A / Agent2Agent Protocol's commits signed?
99% of the last 100 commits to A2A / Agent2Agent Protocol are verified-signed (GPG, SSH, S/MIME, or GitHub's signing flow). Signed commits help confirm that code was authored by who the commit claims.

Not a safety endorsement. HVTracker describes what public signals show, not whether a project is safe for your use case. Run your own security review before adopting in production.

Compare A2A / Agent2Agent Protocol head-to-head

A2A / Agent2Agent Protocol vs MCP Inspector → A2A / Agent2Agent Protocol vs FastMCP (TypeScript) → A2A / Agent2Agent Protocol vs MCP Apps →

AI agent surface

MCP, providers, tool surface
Scored in HVTrust

These runtime-trust fields — detected from public repo docs and manifests — contribute a bounded adjustment to this project's HVTrust score alongside supply-chain evidence. The exact values each field can add or subtract are documented in the methodology → Compare this surface across every listed agent in the capability matrix →

MCP Server Support
None detected
No MCP server signal detected.
Detailed evidence is not shown in the public view.
External Service Dependencies
None detected
No clear third-party provider dependency detected.
Credential signal: No explicit API-key/config marker detected.
Tool / Plugin Surface
high confidence
Extensions
Extension based plugin/integration surface detected.
Detailed evidence is not shown in the public view.
Package Provenance Drift
low confidence
Unknown
Package source metadata is missing or inconclusive
Detailed evidence is not shown in the public view.
  • MCP signal live
  • External deps live
  • Tool / plugin surface live
  • Package provenance drift live

Maintain A2A / Agent2Agent Protocol?

For maintainers

HVTrust scores A2A / Agent2Agent Protocol from public signals only — we never contact maintainers first. If a signal is wrong, stale, or missing (provenance you publish, a Scorecard you run, signed releases), tell us and we'll review it. Corrections are public and tracked on GitHub.

Submit a correction → Add the trust badge

Reputation Timeline

Signal history
Score 1HVTrust 1
2026-05-29
HVTrust Changed
HVTrust up 10.2pts (75.2 → 85.4)
2026-05-28
Activity Score Changed
Activity score up 12pts (67 → 78)
GitHub → PyPI: a2a-sdk

Embed Badge Badge guide for maintainers →

For maintainers
HVTrust 89.4 Grade A
Markdown:
[![HVTrust](https://hvtracker.net/badge/a2a-agent2agent-protocol.svg)](https://hvtracker.net/agents/a2a-agent2agent-protocol)
HTML:
<a href="https://hvtracker.net/agents/a2a-agent2agent-protocol"><img src="https://hvtracker.net/badge/a2a-agent2agent-protocol.svg" alt="HVTrust"></a>

Other agents in Protocols & Tool Integration

Data sources
GitHub REST API (repo, commits, stars, forks, license) · PyPI / pypistats (downloads, provenance) · OpenSSF Scorecard CLI · Algolia HN Search API
Each agent's signals refresh once daily across 6 staggered batches. Methodology v4.3 · Raw JSON