Rust API Reference

PRX-Memory is organized as a Rust workspace with seven crates. Each crate provides a focused API that can be used independently or composed together.

Crate Overview

prx-memory-core

Core domain primitives for scoring, evolution, and memory entry representation.

[dependencies]
prx-memory-core = "0.1"

Key types:

• Memory entry structs with text, scope, tags, importance, and metadata.
• Scoring primitives for relevance ranking.
• Evolution types for train/holdout acceptance testing.

prx-memory-embed

Embedding provider abstraction and adapters.

[dependencies]
prx-memory-embed = "0.1"

Provides an async trait that all embedding providers implement:

// Conceptual API (simplified)
#[async_trait]
pub trait EmbedProvider: Send + Sync {
    async fn embed(&self, texts: &[&str]) -> Result<Vec<Vec<f32>>, EmbedError>;
}

Built-in implementations:

• OpenAiCompatibleProvider -- Any OpenAI-compatible embedding API
• JinaProvider -- Jina AI embeddings
• GeminiProvider -- Google Gemini embeddings

prx-memory-rerank

Rerank provider abstraction and adapters.

[dependencies]
prx-memory-rerank = "0.1"

Provides an async trait for reranking:

// Conceptual API (simplified)
#[async_trait]
pub trait RerankProvider: Send + Sync {
    async fn rerank(
        &self,
        query: &str,
        documents: &[&str],
    ) -> Result<Vec<RerankResult>, RerankError>;
}

Built-in implementations:

• JinaReranker
• CohereReranker
• PineconeReranker

prx-memory-ai

Unified provider abstraction that composes embedding and reranking.

[dependencies]
prx-memory-ai = "0.1"

This crate provides a single entry point for configuring both embedding and reranking providers from environment variables.

prx-memory-skill

Built-in governance skill payloads for MCP resource distribution.

[dependencies]
prx-memory-skill = "0.1"

Provides static skill definitions and payload templates that are discoverable through the MCP resource protocol.

prx-memory-storage

Local persistent storage engine.

[dependencies]
prx-memory-storage = "0.1"

# With LanceDB support
[dependencies]
prx-memory-storage = { version = "0.1", features = ["lancedb-backend"] }

Provides storage trait implementations for:

• JSON file-based storage
• SQLite with vector columns
• LanceDB (optional, behind feature flag)

prx-memory-mcp

MCP server surface that combines all other crates into a runnable daemon.

[dependencies]
prx-memory-mcp = "0.1"

This crate is typically not used as a library dependency -- it provides the prx-memoryd binary.

Error Handling

All crates use thiserror for typed error enums. Errors propagate using the ? operator and are never converted to panics in production code.

// Example error pattern
use thiserror::Error;

#[derive(Error, Debug)]
pub enum EmbedError {
    #[error("API request failed: {0}")]
    Request(#[from] reqwest::Error),
    #[error("API key not configured")]
    MissingApiKey,
    #[error("Unexpected response: {0}")]
    Response(String),
}

Concurrency

• Synchronous mutexes use parking_lot::Mutex (no poisoning).
• Asynchronous mutexes use tokio::sync::Mutex.
• std::sync::Mutex is banned in production code.
• Shared immutable data uses Arc<str> or Arc<T>.

Dependencies

All network requests use reqwest with rustls-tls (no OpenSSL dependency). Serialization uses serde and serde_json.

Next Steps

• Embedding Models -- Provider-specific configuration
• Storage Backends -- Storage trait implementations
• Configuration Reference -- Environment variable reference