ai-lib 🦀✨

A unified, reliable, high-performance multi-provider AI SDK for Rust

A production-grade, provider-agnostic SDK that provides a unified Rust API for 20+ AI platforms and growing (OpenAI, Groq, Anthropic, Gemini, Mistral, Cohere, Azure OpenAI, Ollama, DeepSeek, Qwen, Baidu ERNIE, Tencent Hunyuan, iFlytek Spark, Kimi, HuggingFace, TogetherAI, xAI Grok, OpenRouter, Replicate, Perplexity, AI21, ZhipuAI, MiniMax, and more).
Eliminates fragmented authentication flows, streaming formats, error semantics, model naming differences, and inconsistent function calling. Scale from one-liner scripts to production systems without rewriting integration code.

Official Website

🚀 Core Value

ai-lib unifies AI provider complexity into a single, ergonomic Rust interface:

Universal API: Chat, multimodal, and function calling across all providers
Multimodal Content: Easy image and audio content creation with Content::from_image_file() and Content::from_audio_file()
Unified Streaming: Consistent SSE/JSONL parsing with real-time deltas
Reliability: Built-in retry, timeout, circuit breaker, and error classification
Flexible Configuration: Environment variables, builder pattern, or explicit overrides
Production Ready: Connection pooling, proxy support, observability hooks

Result: Focus on your product logic while ai-lib handles provider integration friction.

Import guidance: In application code, prefer use ai_lib::prelude::*; for a minimal set of common items. Library authors may use explicit imports by domain. See the module tree and import patterns guide: docs/MODULE_TREE_AND_IMPORTS.md.

⚙️ Quick Start

Installation

Basic installation (core features):

[dependencies]

ai-lib = "0.4.0"

tokio = { version = "1", features = ["full"] }

futures = "0.3"

For streaming support, enable the streaming feature:

[dependencies]

ai-lib = { version = "0.4.0", features = ["streaming"] }

tokio = { version = "1", features = ["full"] }

futures = "0.3"

For full functionality (streaming, resilience, routing):

[dependencies]

ai-lib = { version = "0.4.0", features = ["all"] }

tokio = { version = "1", features = ["full"] }

futures = "0.3"

Simple Usage

use ai_lib::prelude::*;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let client = AiClient::new(Provider::Groq)?;
    let req = ChatCompletionRequest::new(
        "llama3-8b-8192".to_string(),
        vec![Message::user("Hello!")]
    );
    let reply = client.chat_completion(req).await?;
    println!("Reply: {}", reply.first_text().unwrap_or_default());
    Ok(())
}

Standard Usage

// Application code can also use the prelude for minimal imports
use ai_lib::prelude::*;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let client = AiClient::new(Provider::OpenAI)?;
    let req = ChatCompletionRequest::new(
        "gpt-3.5-turbo".to_string(), // Explicit model or use client.default_chat_model()
        vec![Message {
            role: Role::User,
            content: Content::Text("Explain Rust ownership in one sentence.".to_string()),
            function_call: None,
        }],
    );
    // .with_extension("parallel_tool_calls", serde_json::json!(true)); // Optional extensions

    let resp = client.chat_completion(req).await?;
    println!("Answer: {}", resp.choices[0].message.content.as_text());
    Ok(())
}

Streaming

Note: Streaming requires the streaming feature (or all feature) to be enabled.

use ai_lib::prelude::*;
use futures::StreamExt;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let client = AiClient::new(Provider::OpenAI)?;
    let req = ChatCompletionRequest::new(
        "gpt-3.5-turbo".to_string(),
        vec![Message::user("Tell me a short story")]
    );

    let mut stream = client.chat_completion_stream(req).await?;
    while let Some(chunk) = stream.next().await {
        let c = chunk?;
        if let Some(delta) = c.choices.get(0).and_then(|ch| ch.delta.content.clone()) {
            print!("{delta}");
        }
    }
    Ok(())
}

🧠 Core Concepts

Concept	Purpose
Provider	Enumerates all supported AI providers
AiClient	Main entry point with unified interface
ChatCompletionRequest	Standardized request payload
Message / Content	Text, image, audio content types
Streaming Event	Provider-standardized delta streams
ConnectionOptions	Runtime configuration overrides
Metrics Trait	Custom observability integration
Transport	Injectable HTTP + streaming layer
Usage / UsageStatus	Response-level usage metadata (tokens + status). Import from `ai_lib::Usage` or `ai_lib::types::response::Usage`

💡 Key Features

Core Capabilities

Unified Provider Abstraction: Single API across all providers
Universal Streaming: Consistent SSE/JSONL parsing with real-time deltas
Multimodal Support: Text, image, and audio content handling
Function Calling: Consistent tool patterns and OpenAI compatibility
Batch Processing: Sequential and concurrent processing strategies

Reliability & Production

Built-in Resilience: Retry with exponential backoff, circuit breakers
Strategy Builders: AiClientBuilder::with_round_robin_chain / with_failover_chain compose routing before runtime
Error Classification: Distinguish transient vs permanent failures
Connection Management: Pooling, timeouts, proxy support
Observability: Pluggable metrics and tracing integration
Security: No sensitive content logging by default

🌍 Supported Providers

17+ providers and growing - We continuously add new AI platforms to support the evolving ecosystem.

Provider	Streaming	Highlights
Groq	✅	Ultra-low latency inference
OpenAI	✅	GPT models, function calling
Anthropic	✅	Claude models, high quality
Google Gemini	✅	Multimodal capabilities
Mistral	✅	European models
Cohere	✅	RAG-optimized
HuggingFace	✅	Open source models
TogetherAI	✅	Cost-effective inference
OpenRouter	✅	Unified gateway, multi-provider model routing
Replicate	✅	Hosted OSS models gateway
DeepSeek	✅	Reasoning models
Qwen	✅	Chinese ecosystem
Baidu ERNIE	✅	Enterprise China
Tencent Hunyuan	✅	Cloud integration
iFlytek Spark	✅	Voice + multimodal
Moonshot Kimi	✅	Long context
Azure OpenAI	✅	Enterprise compliance
Ollama	✅	Local/air-gapped
xAI Grok	✅	Real-time oriented
Perplexity	✅	Search-augmented chat
AI21	✅	Jurassic models
ZhipuAI (GLM)	✅	China GLM series
MiniMax	✅	China multimodal

See examples/ for provider-specific usage patterns.

Gateway Providers

ai-lib supports gateway providers like OpenRouter and Replicate that provide unified access to multiple AI models. Gateway platforms use provider/model format for model naming (e.g., openai/gpt-4o), while direct providers use original model names (e.g., gpt-4o).

🔑 Configuration

Environment Variables

# API Keys (convention-based)

export OPENAI_API_KEY=...

export GROQ_API_KEY=...

export GEMINI_API_KEY=...

export ANTHROPIC_API_KEY=...

export OPENROUTER_API_KEY=...

export REPLICATE_API_TOKEN=...

export PERPLEXITY_API_KEY=...

export AI21_API_KEY=...

export ZHIPU_API_KEY=...

export MINIMAX_API_KEY=...


# Optional: Custom endpoints

export GROQ_BASE_URL=https://custom.groq.com


# Optional: Proxy and timeouts

export AI_PROXY_URL=http://proxy.internal:8080

export AI_TIMEOUT_SECS=30


# Optional: Connection pooling (enabled by default)

export AI_HTTP_POOL_MAX_IDLE_PER_HOST=32

export AI_HTTP_POOL_IDLE_TIMEOUT_MS=90000


# Optional: Override default models per provider

export GROQ_MODEL=llama-3.1-8b-instant

export MISTRAL_MODEL=mistral-small-latest

export DEFAULT_AI_MODEL=gpt-4o-mini

Model Selection & Fallbacks

Auto defaults: Pass "auto" (case-insensitive) or an empty string as the model when constructing ChatCompletionRequest and ai-lib will inject the provider’s preferred model (or your AiClientBuilder::with_default_chat_model override).
Env overrides: Set *_MODEL environment variables (e.g. GROQ_MODEL, OPENAI_MODEL) to change defaults without touching code. These overrides feed the new ModelResolver and apply across builders, streaming, and batch flows.
Invalid-model recovery: When a provider rejects a request with invalid_model/model_not_found, ai-lib now retries with documented fallbacks and surfaces actionable hints (including links such as Groq Models) in the returned AiLibError::ModelNotFound.
Per-provider context: Call client.default_chat_model() to inspect the effective model string that will be used for the next request—handy when composing multi-provider strategies like failover chains.

Programmatic Configuration

use ai_lib::{AiClient, Provider, ConnectionOptions};
use std::time::Duration;

let client = AiClient::with_options(
    Provider::Groq,
    ConnectionOptions {
        base_url: Some("https://custom.groq.com".into()),
        proxy: Some("http://proxy.internal:8080".into()),
        api_key: Some("override-key".into()),
        timeout: Some(Duration::from_secs(45)),
        disable_proxy: false,
    }
)?;

🔌 Bring Your Own Provider

Use CustomProviderBuilder + AiClientBuilder::with_strategy to plug in OpenAI-compatible gateways (self-hosted or vendor previews) without editing the Provider enum. See examples/custom_provider_injection.rs for a full demo.

use ai_lib::{
    client::{AiClientBuilder, Provider},
    provider::builders::CustomProviderBuilder,
    types::{ChatCompletionRequest, Message, Role, Content},
};

let labs_gateway = CustomProviderBuilder::new("labs-gateway")
    .with_base_url("https://labs.example.com/v1")
    .with_api_key_env("LABS_GATEWAY_TOKEN")
    .with_default_chat_model("labs-gpt-35")
    .build_provider()?;

let client = AiClientBuilder::new(Provider::OpenAI) // Enum ignored when strategy is provided
    .with_strategy(labs_gateway)
    .build()?;

let resp = client
    .chat_completion(ChatCompletionRequest::new(
        "labs-gpt-35".to_string(),
        vec![Message {
            role: Role::User,
            content: Content::Text("Hello labs!".to_string()),
            function_call: None,
        }],
    ))
    .await?;
println!("labs> {}", resp.first_text().unwrap_or_default());

Per-provider Builders

Prefer builder wrappers (e.g., GroqBuilder, OpenAiBuilder) when you want clearer configuration or when composing strategies.

use ai_lib::provider::GroqBuilder;

let client = GroqBuilder::new()
    .with_base_url("https://api.groq.com")
    .with_proxy(Some("http://proxy.internal:8080"))
    .build()?; // returns AiClient

Concurrency Control

use ai_lib::{AiClientBuilder, Provider};

let client = AiClientBuilder::new(Provider::Groq)
    .with_max_concurrency(64)
    .for_production()
    .build()?;

🔁 Routing & Failover (OSS)

Use with_failover_chain or with_round_robin_chain to wire strategies before the client sends requests.

use ai_lib::{client::AiClientBuilder, Provider};

let client = AiClientBuilder::new(Provider::OpenAI)
    .with_failover_chain(vec![Provider::Anthropic, Provider::Groq])?
    .build()?;

Combine with with_round_robin_chain or RoutingStrategyBuilder for weighted/round-robin routing. Strategy composition now happens during client construction—no sentinel models or runtime branching required.

🛡️ Reliability & Resilience

Feature	Description
Retry Logic	Exponential backoff with intelligent error classification
Error Handling	Distinguish transient vs permanent failures
Timeouts	Configurable per-request and global timeouts
Proxy Support	Global, per-connection, or disabled proxy handling
Connection Pooling	Tunable pool size and connection lifecycle
Health Checks	Endpoint monitoring and policy-based routing
Fallback Strategies	Multi-provider arrays and manual failover

📊 Observability & Metrics

Custom Metrics Integration

struct CustomMetrics;
#[async_trait::async_trait]
impl ai_lib::metrics::Metrics for CustomMetrics {
    async fn incr_counter(&self, name: &str, value: u64) { /* ... */ }
    async fn start_timer(&self, name: &str) -> Option<Box<dyn ai_lib::metrics::Timer + Send>> { /* ... */ }
}
let client = AiClient::new_with_metrics(Provider::Groq, Arc::new(CustomMetrics))?;

Usage Tracking

match response.usage_status {
    UsageStatus::Finalized => println!("Accurate token counts: {:?}", response.usage),
    UsageStatus::Estimated => println!("Estimated tokens: {:?}", response.usage),
    UsageStatus::Pending => println!("Usage data not yet available"),
    UsageStatus::Unsupported => println!("Provider doesn't support usage tracking"),
}

Migration: Usage/UsageStatus are defined in ai_lib::types::response and re-exported at the root. Old imports from types::common are deprecated and will be removed before 1.0.

Optional Features

By default, ai-lib ships with a minimal feature set. Enable features as needed:

Feature	Description	Alias
`unified_sse`	Common SSE parser for streaming	`streaming`
`interceptors`	Retry, timeout, circuit breaker pipeline	`resilience`
`unified_transport`	Shared HTTP client factory	`transport`
`config_hot_reload`	Config hot-reload traits	`hot_reload`
`cost_metrics`	Basic cost accounting via environment variables	-
`routing_mvp`	Model selection and routing capabilities	-
`observability`	Tracer and AuditSink interfaces	-
`all`	Enable all features above	-

Recommended for most applications:

ai-lib = { version = "0.4.0", features = ["streaming", "resilience"] }

🗂️ Examples

Category	Examples
Getting Started	`quickstart`, `basic_usage`, `builder_pattern`
Configuration	`explicit_config`, `proxy_example`, `custom_transport_config`
Streaming	`test_streaming`, `cohere_stream`
Reliability	`custom_transport`, `resilience_example`
Multi-Provider	`config_driven_example`, `model_override_demo`, `custom_provider_injection`, `routing_modelarray`
Model Management	`model_management`, `routing_modelarray`
Batch Processing	`batch_processing`
Function Calling	`function_call_openai`, `function_call_exec`
Multimodal	`multimodal_example`
Advanced	`architecture_progress`, `reasoning_best_practices`

📄 License

Dual-licensed under MIT or Apache License 2.0 - choose what works best for your project.

🤝 Contributing

Fork & clone repository
Create feature branch: git checkout -b feature/your-feature
Run tests: cargo test
Add examples for new features
Follow adapter patterns (prefer config-driven over custom)
Open PR with rationale + benchmarks (if performance impact)

We value: clarity, test coverage, minimal surface area, incremental composability.

📚 Citation

@software{ai-lib,
    title = {ai-lib: A Unified AI SDK for Rust},
    author = {Luqiang Wang},
    url = {https://github.com/hiddenpath/ai-lib},
    year = {2025}
}

ai-lib 0.4.0