rtb-chat

Part of the phpboyscout Rust toolkit, the small, framework-free crates extracted from rust-tool-base.

Unified multi-provider AI chat client. genai covers the mainstream (OpenAI, Gemini, Ollama, OpenAI-compatible); the two Anthropic providers bypass it and call the Anthropic Messages API directly, for prompt caching, extended thinking and citations. Structured output is JSON-Schema validated before deserialising.

Formerly rtb-ai, renamed at extraction for GTB-family name convergence (Go counterpart: chat.go.phpboyscout.uk). Only the crate identity changed; the API is unchanged.

use rtb_chat::{AiClient, ChatRequest, Config, Message, Provider};
use secrecy::SecretString;

let client = AiClient::new(Config {
    provider: Provider::Anthropic,
    model: "claude-opus-4-7".into(),
    api_key: SecretString::from(std::env::var("ANTHROPIC_API_KEY")?),
    ..Config::default()
})?;
let reply = client.chat(ChatRequest {
    messages: vec![Message::user("Summarise this changelog in one line.")],
    max_tokens: Some(512),
    cache_control: true,
    ..ChatRequest::default()
}).await?;

Config::api_key has no usable default: an empty key is rejected by AiClient::new.

Prompt caching, extended thinking and citations are honoured on the Anthropic backend only. What the other four providers do and do not get is documented in What rtb-chat does not do.

• Docs: https://chat.rust.phpboyscout.uk
  • Tutorial: your first chat call
  • How-to guides
  • Reference
  • Explanation
• API reference: https://docs.rs/rtb-chat
• Crate: https://crates.io/crates/rtb-chat

Development

just ci runs the full local gate (fmt, clippy, nextest, doc, deny). The test suite runs entirely against wiremock, so no provider API keys are needed. Releases are cut by colophon from Conventional Commits; do not tag manually.

License

MIT