yoi/crates/agen-macros

agen-macros

Procedural macros used by agen to declare LLM tools from Rust methods.

Applications should normally depend only on agen and import its re-exports:

use agen::tool_registry;

#[derive(Clone)]
struct Tools;

#[tool_registry]
impl Tools {
    /// Returns the supplied text.
    #[tool]
    async fn echo(
        &self,
        #[description = "Text to return"] text: String,
    ) -> Result<String, std::io::Error> {
        Ok(text)
    }
}

#[tool_registry] generates the argument schema, a Tool implementation, and an <method>_definition constructor. It rejects arguments of its own, duplicate #[tool] markers, malformed or duplicate #[description = "..."] attributes, and non-identifier argument patterns.

Generated code targets the canonical ::agen path and uses implementation dependencies re-exported by agen; consumers do not need direct serde, schemars, serde_json, or async-trait dependencies. Renaming the agen dependency in Cargo.toml is not currently supported.

This companion package is published before the matching agen release. Its public contract is the generated API consumed by agen, and its minor version compatibility follows the agen 0.2 series.

Licensed under the MIT License.