A2a4j
A Java toolkit for developers building Agent2Agent Protocol clients and servers.
Listed automaticallyPrice not confirmedDeveloper
Similar agents · November 2026
Alternatives to A2a4j
Agents that do similar work to A2a4j. A2a4j is listed first for reference. 20 agents match at least two tags or a task; we use the normal search ranking and show verification labels.
Reference agent
Similar agents
Ranked by shared tags and taskCompanyOS
A self-hostable agent platform for teams to build, deploy, and coordinate always-on company agents.
Listed automaticallyOpen sourceDeveloper
Univer
An open-source office SDK for developers adding document editing and collaboration to their products.
Listed automaticallyOpen sourceDeveloper
Learn Agent
Practical coding-agent development notes and runnable examples for agent builders.
Listed automaticallyPrice not confirmedDeveloper
TapeAgents
A developer framework for building, debugging, serving, and optimizing LLM agents.
Listed automaticallyPrice not confirmedDeveloper
Palico AI
A developer toolkit for building, evaluating, and deploying LLM applications.
Listed automaticallyPrice not confirmedDeveloper
AntOmniEvo
A developer framework that evolves and optimizes AI agents, workflows, and algorithms.
Listed automaticallyOpen sourceDeveloper
AI Agents From Scratch
A hands-on guide for developers learning to build AI agents from scratch.
Listed automaticallyPrice not confirmedDeveloper
Erd Editor
Design database schemas and generate code for developers working in browser-based or IDE workflows.
Listed automaticallyPrice not confirmedDeveloper
Fusio
Self-hosted API platform for builders creating services and tools for AI agents.
Listed automaticallyOpen sourceDeveloper
Cortex
Generates API documentation, SDKs, and MCP servers for developers.
Listed automaticallyPrice not confirmedDeveloper
Java SDK
A Java SDK for developers building Model Context Protocol servers and clients.
Listed automaticallyPrice not confirmedDeveloper
Csharp SDK
A C# SDK for developers building Model Context Protocol servers and clients.
Listed automaticallyPrice not confirmedDeveloper
Typescript SDK
A TypeScript SDK for developers building Model Context Protocol servers and clients.
Listed automaticallyPrice not confirmedDeveloper
Sera Agents
Developer tools and templates for integrating multi-currency settlement into AI agents.
Listed automaticallyPrice not confirmedDeveloper
PCM Protocol
An open-source protocol for developers building AI agents that verify evidence behind messages.
Listed automaticallyOpen sourceDeveloper
Cogneva
A self-deploying multi-agent framework for developers building autonomous AI systems.
Listed automaticallyOpen sourceDeveloper
Agentic Commerce Skills Plugins
Commerce protocol and platform plugins for developers building agentic commerce integrations.
Listed automaticallyPrice not confirmedDeveloper
Agentify
Developer tool that turns OpenAPI specs into interfaces for AI agents.
Listed automaticallyPrice not confirmedDeveloper
Agent Identity Discovery
An open standard and developer toolkit for making agent endpoints discoverable by domain.
Listed automaticallyOpen sourceDeveloper
A2a In Action
A2A code examples that help beginners learn the protocol through hands-on practice.
Listed automaticallyPrice not confirmedDeveloper
Built an alternative?
If your agent does similar work, add it to the index so buyers can compare it fairly.
List it free