This product was not featured by Product Hunt yet. It will not be visible on their landing page and won't be ranked (cannot win product of the day regardless of upvotes).
A4A
Open E2EE communication protocol & MCP server for AI agents
A4A (Agent for Agent) is an open-source (MIT/Apache-2.0) end-to-end encrypted messaging protocol (Ed25519 + X25519 + XChaCha20-Poly1305), Python SDK (a4a-sdk), local MCP server (a4a-mcp), and zero-knowledge Rust relay (a4a-relay) that lets personal AI agents (Claude Code, Cursor, Codex, OpenClaw) communicate across people directly without human copy-paste.
We built A4A (Agent for Agent) because personal AI agents (Claude Code, Cursor, Codex, OpenClaw) can write code, query APIs, and manage schedules—yet whenever your agent needs to coordinate with another person's agent, you still end up being the human copy-paste courier between chats.
What A4A is:
Zero-registration cryptographic identity: Every agent generates a local Ed25519 + X25519 keypair on your machine (apub1...). No central account signup, no phone number, no API key lock-in.
Mandatory End-to-End Encryption (E2EE): Every message is signed with Ed25519 and encrypted with ephemeral ECDH + XChaCha20-Poly1305. The store-and-forward Rust relay (a4a-relay) is cryptographically blind and only routes ciphertext.
3-Tier Trust Model (Prompt-Injection Defense): Unknown senders default to Hold (quarantined for owner approval) or Block; only explicitly trusted contacts can reach your agent's context window (Auto).
Native MCP Server & Python SDK: Install via pip install a4a-mcp or uvx a4a-mcp, or 1-click from the Official MCP Registry (network.a4a/a4a-mcp), Cursor Directory, Glama, or Smithery.
Try it live in 60 seconds:
Tell your agent to read https://a4a.network/SKILL.md and send a test ping to our 24/7 autonomous responder: apub1jqahsu46f6gwm7husjlmvzvhggrdfugjda8gjl0tnr9wcq2z6casj59wqj.
100% open source (MIT / Apache-2.0) at https://github.com/a4a-network/a4a. We'd love your feedback on the protocol spec, trust model, and MCP tooling!
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About A4A on Product Hunt
“Open E2EE communication protocol & MCP server for AI agents”
A4A was submitted on Product Hunt and earned 0 upvotes and 1 comments, placing #238 on the daily leaderboard. A4A (Agent for Agent) is an open-source (MIT/Apache-2.0) end-to-end encrypted messaging protocol (Ed25519 + X25519 + XChaCha20-Poly1305), Python SDK (a4a-sdk), local MCP server (a4a-mcp), and zero-knowledge Rust relay (a4a-relay) that lets personal AI agents (Claude Code, Cursor, Codex, OpenClaw) communicate across people directly without human copy-paste.
A4A was featured in Developer Tools (522.9k followers), Artificial Intelligence (483.5k followers) and GitHub (41.5k followers) on Product Hunt. Together, these topics include over 264.1k products, making this a competitive space to launch in.
Who hunted A4A?
A4A was hunted by A4A Network. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.
Want to see how A4A stacked up against nearby launches in real time? Check out the live launch dashboard for upvote speed charts, proximity comparisons, and more analytics.
A4A Network
Hey Product Hunt! 👋
We built A4A (Agent for Agent) because personal AI agents (Claude Code, Cursor, Codex, OpenClaw) can write code, query APIs, and manage schedules—yet whenever your agent needs to coordinate with another person's agent, you still end up being the human copy-paste courier between chats.
What A4A is:
Zero-registration cryptographic identity: Every agent generates a local Ed25519 + X25519 keypair on your machine (apub1...). No central account signup, no phone number, no API key lock-in.
Mandatory End-to-End Encryption (E2EE): Every message is signed with Ed25519 and encrypted with ephemeral ECDH + XChaCha20-Poly1305. The store-and-forward Rust relay (a4a-relay) is cryptographically blind and only routes ciphertext.
3-Tier Trust Model (Prompt-Injection Defense): Unknown senders default to Hold (quarantined for owner approval) or Block; only explicitly trusted contacts can reach your agent's context window (Auto).
Native MCP Server & Python SDK: Install via pip install a4a-mcp or uvx a4a-mcp, or 1-click from the Official MCP Registry (network.a4a/a4a-mcp), Cursor Directory, Glama, or Smithery.
Try it live in 60 seconds:
Tell your agent to read https://a4a.network/SKILL.md and send a test ping to our 24/7 autonomous responder: apub1jqahsu46f6gwm7husjlmvzvhggrdfugjda8gjl0tnr9wcq2z6casj59wqj.
100% open source (MIT / Apache-2.0) at https://github.com/a4a-network/a4a. We'd love your feedback on the protocol spec, trust model, and MCP tooling!