PRAXO-CORE Java Core¶

Java implementation of the PRAXO-CORE contract. The normative contract is spec/; Go remains the reference implementation.

Status: The package passes all eleven conformance vector groups. Context budgets, middleware, streaming, virtual-thread execution, cancellation, the OpenAI-compatible adapter, and the agent loop are included. VFS and plugin hosts are not yet implemented.

Package version: 0.2.2. Supported contract: SPEC_VERSION 0.2.0 (io.axisvela.praxo.Version.SPEC_VERSION).

Requirements¶

Java 21 or newer
Maven 3.9 or newer

Build and test¶

cd language/java
mvn -q -DskipTests test-compile
mvn -q -DskipTests package
java -cp target/classes io.axisvela.praxo.conformance.ApiSnapshot --check
java -cp target/classes io.axisvela.praxo.conformance.Run
java --add-modules jdk.httpserver -cp target/classes:target/test-classes io.axisvela.praxo.adapters.OpenAICompatibleSelfTest
java -cp target/classes:target/test-classes io.axisvela.praxo.agent.AgentConcurrencySelfTest

Usage¶

import io.axisvela.praxo.agent.Agent;
import io.axisvela.praxo.agent.AgentOptions;
import io.axisvela.praxo.agent.Session;
import io.axisvela.praxo.model.Message;
import io.axisvela.praxo.model.Request;
import io.axisvela.praxo.model.Response;
import io.axisvela.praxo.tool.FuncTool;
import io.axisvela.praxo.tool.Registry;

var tools = new Registry();
tools.register(new FuncTool("echo", "Echo", args -> args));

var agent = new Agent(new AgentOptions(request -> Response.of(
        Message.assistant("hello", java.util.List.of()))));
var result = agent.run(new Session("session-1"), "hi");
System.out.println(result.output + " " + result.steps);

Contract Surface¶

Package	Contract
`io.axisvela.praxo.model`	Model, messages, tool specs, request/response, usage
`io.axisvela.praxo.tool`	Tool, Registry, FuncTool
`io.axisvela.praxo.event`	Event, Sink, multi/filter sinks
`io.axisvela.praxo.policy`	Hook, Decision, PathChecker
`io.axisvela.praxo.memory`	Store, MemoryRecord, MemoryStore
`io.axisvela.praxo.checkpoint`	Allowlist
`io.axisvela.praxo.context`	budgets, summarization, offload, AGENTS.md
`io.axisvela.praxo.middleware`	call limits, fallback, PII, structured output, tool selection
`io.axisvela.praxo.agent`	Agent, AgentOptions, Session, Result
`io.axisvela.praxo.toolcall`	tool-call parsing and markup stripping
`io.axisvela.praxo.jsonschema`	documented JSON Schema subset
`io.axisvela.praxo.plugin`	Manifest v1 parsing and validation
`io.axisvela.praxo.adapters`	OpenAI-compatible non-streaming and SSE adapter

Wire codecs preserve the Go names, including image_url, runId, and plugin_id. The Java Core uses a dependency-free JSON utility (util/Json.java) with no runtime dependencies. Model and tool calls run on virtual threads with CancellationToken-based cancellation.

Conformance¶

The runner reads ../../spec/vectors/*.json. A released Core implementation must pass every vector and keep spec/parity.md current.

License¶

MIT. See LICENSE.