chat-gemini

Google Gemini provider for chat-rs.

Install

[dependencies]
chat-core = "0.4.0"
chat-gemini = "0.2.4"
tokio = { version = "1", features = ["macros", "rt-multi-thread"] }

Or via the umbrella crate: chat-rs = { version = "0.5.0", features = ["gemini"] }.

Usage

use chat_gemini::GeminiBuilder;
use chat_core::{builder::ChatBuilder, types::messages};

let client = GeminiBuilder::new()
    .with_model("gemini-2.5-flash".to_string())
    .build();

let mut chat = ChatBuilder::new().with_model(client).build();

let mut msgs = messages::from_user(vec!["Hello!"]);
let response = chat.complete(&mut msgs).await?;

Set GEMINI_API_KEY in your environment or call .with_api_key() on the builder.

Capabilities

• Completions — text generation with tool calling and structured output
• Streaming — token-by-token output (requires stream feature)
• Embeddings — vector embeddings via .with_embeddings(dimensions)
• Extended thinking — enable with .with_thoughts(true)

Custom Transport

Supply a custom transport via .with_transport() to use something other than the default HTTP (reqwest):

let client = GeminiBuilder::new()
    .with_model("gemini-2.5-flash".to_string())
    .with_transport(my_transport)
    .build();

Native Tools

• Google Search — .with_google_search() or .with_google_search_threshold(f32)
• Code Execution — .with_code_execution()
• Google Maps — .with_google_maps(lat_lng, widget)

Feature Flags

Streaming is gated on the stream feature:

chat-gemini = { version = "0.2.3", features = ["stream"] }