PRAXO-CORE Rust Core¶

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

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

Package version: 0.1.1. Supported contract: SPEC_VERSION 0.2.0 (praxo_core::SPEC_VERSION).

Requirements¶

Rust 1.80 or newer
Python 3.10 or newer for the API gate (not a runtime dependency)

Build and test¶

cd language/rust
cargo test
cargo run --quiet --bin conformance
python api-snapshot.py --check
python -m unittest discover -s tests -p "test_*.py" -v

Usage¶

use std::sync::Arc;
use praxo_core::agent::{Agent, AgentOptions, Session};
use praxo_core::model::{Message, Model, Request, Response};

struct EchoModel;

impl Model for EchoModel {
    fn generate(&self, _request: &Request) -> praxo_core::errors::Result<Response> {
        Ok(Response {
            message: Message::assistant("hello", Vec::new()),
            ..Response::default()
        })
    }
}

let agent = Agent::new(AgentOptions::new(Arc::new(EchoModel)))?;
let result = agent.run(&Session::new("session-1"), "hi")?;
println!("{} {}", result.output, result.steps);

Contract Surface¶

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

Wire codecs preserve the Go names, including image_url, runId, and plugin_id.

Conformance¶

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

API Gate¶

api-snapshot.py uses stable compiler-generated rustdoc, not a source regex scanner. It records reachable public declarations, fields, inherent methods, and direct trait implementations, and checks implemented symbols against spec/parity/rust.md. Stale, unlinked rustdoc pages are excluded. Auto traits, blanket implementations, and expanded alias internals are excluded to avoid compiler/platform-specific noise.

The baseline is api/0.1.0.txt. Regenerate it with python api-snapshot.py only after reviewing an intentional API change. This is not a binary ABI or automated semver-compatibility guarantee. Serde/wire attributes still require specification review and conformance tests; they are not inferred from rustdoc. The gate uses Cargo.lock and adds no Rust dependencies.

License¶

MIT. See LICENSE.