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a2aproject
A2A
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a2aproject / A2A

A2A

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

Systems & InfrastructureAI & Machine Learning
Explore on GitHubRead Hacker News discussions
12Distinct people
13Mentions
0Explicit recommenders
26.5KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

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

GitHub

Where it is used

No documented product use was verified in the last source check.

What people are saying

No recommendation phrase was found in the indexed comments.

No classified warning is attached to this page. Read the discussions before treating silence as approval.

Also in these discussions

No other repository is repeatedly linked in the same discussions.

This week on Hacker News

Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 1:49:46 PM UTC.

No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.

Mentions over time

HN mentions by month13 dated mentions

Observed mentions: 2025-04-09 13:40:18 UTC to 2026-06-18 08:52:45 UTC.

02468102025-04-01 00:00:00 UTC to 2025-05-01 00:00:00 UTC (exclusive): 9 mentions; 2 submissions, 7 commentsApr 20252025-05-01 00:00:00 UTC to 2025-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-06-01 00:00:00 UTC to 2025-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-07-01 00:00:00 UTC to 2025-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-08-01 00:00:00 UTC to 2025-09-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2025-09-01 00:00:00 UTC to 2025-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-10-01 00:00:00 UTC to 2025-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-11-01 00:00:00 UTC to 2025-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsNov 20252025-12-01 00:00:00 UTC to 2026-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-01-01 00:00:00 UTC to 2026-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-02-01 00:00:00 UTC to 2026-03-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2026-03-01 00:00:00 UTC to 2026-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-04-01 00:00:00 UTC to 2026-05-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 comments2026-05-01 00:00:00 UTC to 2026-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2026-06-01 00:00:00 UTC to 2026-07-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsJun 2026

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Apr 20252025-04-01 00:00:00 UTC2025-05-01 00:00:00 UTC927
May 20252025-05-01 00:00:00 UTC2025-06-01 00:00:00 UTC000
Jun 20252025-06-01 00:00:00 UTC2025-07-01 00:00:00 UTC000
Jul 20252025-07-01 00:00:00 UTC2025-08-01 00:00:00 UTC000
Aug 20252025-08-01 00:00:00 UTC2025-09-01 00:00:00 UTC101
Sep 20252025-09-01 00:00:00 UTC2025-10-01 00:00:00 UTC000
Oct 20252025-10-01 00:00:00 UTC2025-11-01 00:00:00 UTC000
Nov 20252025-11-01 00:00:00 UTC2025-12-01 00:00:00 UTC000
Dec 20252025-12-01 00:00:00 UTC2026-01-01 00:00:00 UTC000
Jan 20262026-01-01 00:00:00 UTC2026-02-01 00:00:00 UTC000
Feb 20262026-02-01 00:00:00 UTC2026-03-01 00:00:00 UTC101
Mar 20262026-03-01 00:00:00 UTC2026-04-01 00:00:00 UTC000
Apr 20262026-04-01 00:00:00 UTC2026-05-01 00:00:00 UTC110
May 20262026-05-01 00:00:00 UTC2026-06-01 00:00:00 UTC000
Jun 20262026-06-01 00:00:00 UTC2026-07-01 00:00:00 UTC110

What Hacker News says

13 sources
asim·Jun 18, 2026Submission

Ask HN: Is anyone using the A2A protocol?

The A2A protocol is an agent to agent protocol from Google. I was looking at it 6 months back but it didn't feel like I really understood how to use it at that point. Probably because we were all still trying to figure out agents and then the MCP protocol became quite a big deal. But now I'm starting to think that once an agent has tools and services and data and then contacts. Actually, the point of interaction becomes the agent itself and then if you build other agents you would want them to interact because they have the most relevant context and ability to answer whatever queries. So I was just curious to know if anyone is using this yet? https://github.com/a2aproject/A2A
96 points · Open discussion
benclarkeio·Apr 10, 2026Submission

Show HN: A2A Utils – a comprehensive set of utility functions for A2A servers

I’ve been working on the A2A Utils [1] package, a comprehensive set of utility functions for using A2A servers (remote agents). It has been three weeks in the making, and is based on nearly a year’s experience using A2A servers in production. The A2A MCP Server [2] and OpenClaw A2A Plugin [3] are wrappers around it, and it will power other packages in the near future. If you are planning on using A2A servers, I highly encourage you to read through the documentation for 30 minutes. I promise it will save you at least 10x that time! A quick introduction to A2A. A2A standardises agent discovery, communication, and authentication. The protocol introduces the concept of an Agent Card, a JSON object containing the agent’s name, description, skills, accepted inputs, outputs, and authentication methods. It also defines a Message, a Task (a unit o
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f work), an Artifact (the output of a Task), and a Part (a fundamental object for Messages and Artifacts that can represent text, data, and files). Most people associate A2A with multi-agent systems, but it also serves as a framework for deploying agents. You get a standardised API endpoint for sending text, data, and files from any A2A compatible SDK, UI, or app. Agent Cards can be used to catalog and search agents. And A2A was explicitly designed for long-running, asynchronous tasks with support for polling, streaming, and webhooks. To learn more, see What is A2A? [4] Check the GitHub discussion out, where I compare sending a Message and polling a Task with the A2A SDK and A2A Utils. I think it's much more elegant! I would love to hear your thoughts and welcome feedback. Links: [1] A2A Utils: https://github.com/a2anet/a2a-utils [2] A2A MCP Server: https://github.com/a2anet/a2a-mcp [3] OpenClaw A2A Plugin: https://github.com/a2anet/openclaw-a2a-plugin [4] What is A2A?: https://a2a-protocol.org/latest/topics/what-is-a2a/#core-ben...
2 points · Open discussion
joshuafuller·Feb 9, 2026
Have you looked at the Linux Foundations (Formerly Google Project) under the nearly identical name ? https://github.com/a2aproject/A2A There are many sub projects for the various languages like Go, Python, etc Edit: to be clear, A2A does not include payment functions but it has some projects close to it that look like it’s trying to solve the same thing. A2P comes to mind from Google: https://cloud.google.com/blog/products/ai-machine-learning/a...
In Show HN: A2A Protocol – Infrastructure for an Agent-to-Agent Economy
jasonjmcghee·Aug 27, 2025
So this ACP is Agent Client Protocol https://github.com/zed-industries/agent-client-protocol not to be confused with the other ACP from IBM, Agent Communication Protocol... Which is about "communication between agents, humans, and applications". https://github.com/i-am-bee/ACP Which is now part of A2A https://github.com/a2aproject/A2A I'm curious if there was an attempt to extend this to add first class support for interaction with IDEs rather than creating a new protocol.
In Bring Your Own Agent to Zed – Featuring Gemini CLI
TS_Posts·Apr 12, 2025
(I work on a2a) Thank you for the feedback? Would you consider writing up an issue on our github with some more specifics? https://github.com/google/a2a A2A is being developed in the open with the community. You are finding some early details that we are looking into and will be addressing. We have many partners who will be contributing and want this to be a truly open, collaborative endeavor. We acknowledge this is a little different than dropping a polished '1.0' version in github on day 1. But that is intentional :)
In The Agent2Agent Protocol (A2A)
Flux159·Apr 9, 2025
Some very quick initial thoughts - the json spec has some similarities to mcp: https://google.github.io/A2A/#/documentation?id=agent-card - there's an agent card that describes capabilities that google wants websites to host at https://DOMAIN/.well-known/agent.json according to https://google.github.io/A2A/#/topics/agent_discovery so crawlers can scrape to discover agents. The jsonrpc calls look similar-ish to mcp tool calls except the inputs and outputs look closer to the inputs/outputs from calling an LLM (ie messages, artifacts, etc.). The JS server example that they give is interesting https://github.com/google/A2A/tree/main/samples/js/src/serve... - they're using a generator to send sse events back to the caller - a little weird to expose as the API instead of just doing what express allows you to do after setting up an sse connectio
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n (res.send / flush multiple times).
In The Agent2Agent Protocol (A2A)
_pdp_·Apr 9, 2025
Link to repo: https://github.com/google/A2A Docs: https://google.github.io/A2A/#/documentation I think they are trying to ride the MCP hype as well with their own implementation that is also meh. MCP itself is also an over-engineered implementation of AI plugins by OpenAI. Obviously the end game is control over a standard which can act as a strategic tool for boosting valuations or even better product positioning. The better approach is to simply use open standards that already exists but I guess this is just not sexy.
In The Agent2Agent Protocol (A2A)

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