a2a-t-sdk-java

Java SDK used to generate task prompts and handle task negotiation flows based on the A2A-T protocol.
基于A2A-T协议用于生成任务提示词并处理任务协商流程的Java SDK。

中文

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Project Overview

a2a-t-sdk-java is a Java SDK targeting telecom scenarios, used to generate task prompts and handle task negotiation flows.

This SDK is primarily aimed at two types of users:

• Client: Generates task prompts based on user input, and initiates, receives, and advances negotiation flows.
• Server: Validates A2A-T protocol messages that conform to the SDK format, and initiates, receives, and advances negotiation flows.

Core Capabilities

• Task prompt generation pipeline: Covers input normalization, scenario recognition, slot extraction, and task prompt rendering.
• Client API: Provides a task prompt generation result stream, along with negotiation entry points such as start_negotiation, receive_negotiation, and continue_negotiation.
• Server validation API: Targets A2A-T protocol messages that conform to the SDK format, performing metadata parsing, slot extraction.
• Negotiation types: Includes four built-in negotiation types: information.
• Resource organization: Built-in prompt resources are located in a2a-t-resources/src/main/resources/prompt_resources, containing prompts, scenarios, slots, and templates.
• Built-in example scenario: Currently, the package provides scenarios such assubscribe_incident.

Project Structure

The repository is organized as a Maven multi-module reactor, with core code under each module's src/main/java. The main modules are:

• a2a-t-bom: Bill of materials (BOM) that aligns library module versions.
• a2a-t-core: Shared .env-driven configuration loading, value types, JSON parsing abstractions, and the exception processing.
• a2a-t-resources: Packaging and classpath loading of built-in prompt resources.
• a2a-t-llm: LLM adapter layer, LLMs can be customized and connected. By default, OpenAIClient is provided, and LLMs compatible with OpenAI specifications can be connected.
• a2a-t-prompt: Prompt resource model and loading, scenario recognition, slot extraction, and template rendering.
• a2a-t-negotiation: Negotiation types, runtime state machine, and state storage.
• a2a-t-client: Client facade providing task prompt generation and negotiation entry points.
• a2a-t-server: Server facade providing processed task prompt validation and negotiation entry points.
• a2a-t-sample: Runnable client/server sample.

Installation and Environment Requirements

• Java requirement: >=17
• Build tool: Maven (no wrapper is bundled; install it locally)
• Group ID: net.openan.a2a-t.sdk
• License: Apache-2.0
• It is recommended to import a2a-t-bom to align module versions:

Before starting, edit client.env / server.env at the repo root (or refer to env.example) and fill in a valid A2AT_LLM_API_KEY and other settings.

Development and Testing

The project uses a Maven multi-module reactor build, with code formatting unified by spotless-maven-plugin (Palantir Java Format) and tests based on JUnit 5 (Jupiter).

Each module's src/test/java mirrors the main package structure, covering the negotiation state machine, the four negotiation type handlers, classpath and local-file loaders, prompt rendering, and client/server orchestration. For a runnable end-to-end sample, see a2a-t-sample and a2a-t-sample/README.zh-CN.md.

Current Scope of Support

Before use, it is recommended to confirm the following limitations:

• The built-in LLM invocation chain is unified externally as an OpenAI adaptation layer.
• Prompt resources currently only support local files.
• Negotiation state storage currently only provides an in-memory implementation and does not guarantee persistence.
• The bundled resources and language coverage are limited, and do not include remote resource loading capabilities such as registry-center.
• This document primarily introduces the SDK itself, and does not cover the CLI, hosted services, deployment processes, or ready-to-use application solutions.

License

This project is licensed under the Apache-2.0 license.