meerkat-tools 0.5.1

//! Load skill tool — activates a skill mid-turn.

use std::sync::Arc;

use async_trait::async_trait;
use meerkat_core::ToolDef;
use meerkat_core::skills::{SkillId, SkillRuntime};
use serde::Deserialize;
use serde_json::{Value, json};

use crate::builtin::{BuiltinTool, BuiltinToolError, ToolOutput};

/// Arguments for the load_skill tool (used for schema generation).
#[derive(Debug, Deserialize, schemars::JsonSchema)]
#[allow(dead_code)]
struct LoadSkillArgs {
    /// Canonical skill ID (e.g. "extraction/email-extractor").
    id: String,
}

/// Tool for loading a skill's full instructions into the conversation.
pub struct LoadSkillTool {
    engine: Arc<SkillRuntime>,
}

impl LoadSkillTool {
    pub fn new(engine: Arc<SkillRuntime>) -> Self {
        Self { engine }
    }
}

#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
impl BuiltinTool for LoadSkillTool {
    fn name(&self) -> &'static str {
        "load_skill"
    }

    fn def(&self) -> ToolDef {
        ToolDef {
            name: "load_skill".into(),
            description: "Load a skill's full instructions into the conversation.".into(),
            input_schema: crate::schema::schema_for::<LoadSkillArgs>(),
        }
    }

    fn default_enabled(&self) -> bool {
        false // Enabled conditionally when skills are active
    }

    async fn call(&self, args: Value) -> Result<ToolOutput, BuiltinToolError> {
        let id_str = args.get("id").and_then(|v| v.as_str()).ok_or_else(|| {
            BuiltinToolError::InvalidArgs("Missing required 'id' parameter".into())
        })?;

        let skill_id = SkillId(id_str.to_string());
        let results = self
            .engine
            .resolve_and_render(&[skill_id])
            .await
            .map_err(|e| BuiltinToolError::ExecutionFailed(e.to_string()))?;

        match results.into_iter().next() {
            Some(resolved) => Ok(ToolOutput::Json(json!({
                "id": resolved.id.0,
                "canonical_key": canonical_key(&resolved.id),
                "name": resolved.name,
                "body": resolved.rendered_body,
                "byte_size": resolved.byte_size,
            }))),
            None => Err(BuiltinToolError::ExecutionFailed(
                "Skill resolved but returned no content".into(),
            )),
        }
    }
}

fn canonical_key(id: &SkillId) -> Value {
    match id.0.split_once('/') {
        Some((source_uuid, skill_name)) => {
            json!({ "source_uuid": source_uuid, "skill_name": skill_name })
        }
        None => json!({ "source_uuid": Value::Null, "skill_name": id.0 }),
    }
}

#[cfg(test)]
#[allow(clippy::unwrap_used, clippy::manual_async_fn)]
mod tests {
    use super::*;
    use meerkat_core::skills::{
        ResolvedSkill, SkillArtifact, SkillArtifactContent, SkillCollection, SkillDescriptor,
        SkillEngine, SkillError, SkillFilter, SkillScope,
    };

    struct MockEngine {
        skills: Vec<SkillDescriptor>,
    }

    impl SkillEngine for MockEngine {
        fn inventory_section(
            &self,
        ) -> impl std::future::Future<Output = Result<String, SkillError>> + Send {
            async move { Ok(String::new()) }
        }

        fn resolve_and_render(
            &self,
            ids: &[SkillId],
        ) -> impl std::future::Future<Output = Result<Vec<ResolvedSkill>, SkillError>> + Send
        {
            let ids = ids.to_vec();
            async move {
                let mut results = Vec::new();
                for id in &ids {
                    if let Some(skill) = self.skills.iter().find(|s| &s.id == id) {
                        results.push(ResolvedSkill {
                            id: id.clone(),
                            name: skill.name.clone(),
                            rendered_body: format!("<skill id=\"{}\">Body content</skill>", id.0),
                            byte_size: 30,
                        });
                    } else {
                        return Err(SkillError::NotFound { id: id.clone() });
                    }
                }
                Ok(results)
            }
        }

        fn collections(
            &self,
        ) -> impl std::future::Future<Output = Result<Vec<SkillCollection>, SkillError>> + Send
        {
            async move { Ok(vec![]) }
        }

        fn list_skills(
            &self,
            _filter: &SkillFilter,
        ) -> impl std::future::Future<Output = Result<Vec<SkillDescriptor>, SkillError>> + Send
        {
            async move { Ok(self.skills.clone()) }
        }

        fn quarantined_diagnostics(
            &self,
        ) -> impl std::future::Future<
            Output = Result<Vec<meerkat_core::skills::SkillQuarantineDiagnostic>, SkillError>,
        > + Send {
            async move { Ok(Vec::new()) }
        }

        fn health_snapshot(
            &self,
        ) -> impl std::future::Future<
            Output = Result<meerkat_core::skills::SourceHealthSnapshot, SkillError>,
        > + Send {
            async move { Ok(meerkat_core::skills::SourceHealthSnapshot::default()) }
        }

        fn list_artifacts(
            &self,
            _id: &SkillId,
        ) -> impl std::future::Future<Output = Result<Vec<SkillArtifact>, SkillError>> + Send
        {
            async move { Ok(Vec::new()) }
        }

        fn read_artifact(
            &self,
            id: &SkillId,
            _artifact_path: &str,
        ) -> impl std::future::Future<Output = Result<SkillArtifactContent, SkillError>> + Send
        {
            let id = id.clone();
            async move { Err(SkillError::NotFound { id }) }
        }

        fn invoke_function(
            &self,
            id: &SkillId,
            _function_name: &str,
            _arguments: Value,
        ) -> impl std::future::Future<Output = Result<Value, SkillError>> + Send {
            let id = id.clone();
            async move { Err(SkillError::NotFound { id }) }
        }
    }

    fn test_engine() -> Arc<SkillRuntime> {
        Arc::new(SkillRuntime::new(Arc::new(MockEngine {
            skills: vec![SkillDescriptor {
                id: SkillId("extraction/email".into()),
                name: "email".into(),
                description: "Extract from emails".into(),
                scope: SkillScope::Builtin,
                ..Default::default()
            }],
        })))
    }

    #[tokio::test]
    async fn test_load_skill_returns_body() {
        let tool = LoadSkillTool::new(test_engine());
        let result = tool
            .call(json!({"id": "extraction/email"}))
            .await
            .unwrap()
            .into_json()
            .unwrap();

        assert_eq!(result["id"], "extraction/email");
        assert_eq!(result["name"], "email");
        assert!(result["body"].as_str().unwrap().contains("Body content"));
        assert!(result["byte_size"].as_u64().unwrap() > 0);
    }

    #[tokio::test]
    async fn test_load_skill_not_found() {
        let tool = LoadSkillTool::new(test_engine());
        let result = tool.call(json!({"id": "nonexistent/skill"})).await;

        assert!(result.is_err());
    }
}