aether-agent-core 0.6.37

//! Agent specification types for authored agent definitions.
//!
//! `AgentSpec` is the canonical abstraction for authored agent definitions across the stack.
//! It represents a resolved runtime type, not a raw settings DTO.

use crate::core::Prompt;
use llm::{LlmModel, ModelSettings, ProviderConnectionOverrides, ReasoningEffort};
use mcp_utils::client::{McpConfig, ToolFilter};
use std::path::PathBuf;

#[derive(Debug, Clone)]
pub enum McpConfigSource {
    File { path: PathBuf, defer_tools: bool },
    Json(String),
    Inline(McpConfig),
}

impl McpConfigSource {
    pub fn file(path: PathBuf, defer_tools: bool) -> Self {
        Self::File { path, defer_tools }
    }

    pub fn model_visible(path: PathBuf) -> Self {
        Self::file(path, false)
    }

    pub fn deferred(path: PathBuf) -> Self {
        Self::file(path, true)
    }
}

/// A resolved agent specification ready for runtime use.
///
/// This type is produced by validating and resolving authored agent configuration.
/// All validation happens before constructing these runtime types.
#[derive(Debug, Clone)]
pub struct AgentSpec {
    /// The canonical lookup key for this agent.
    pub name: String,
    /// Human-readable description of this agent's purpose.
    pub description: String,
    /// The validated model spec to use for this agent.
    ///
    /// This is stored as a canonical string so authored settings can represent
    /// both single models (`provider:model`) and alloy specs
    /// (`provider1:model1,provider2:model2`).
    pub model: String,
    /// Optional reasoning effort level for models that support it.
    pub reasoning_effort: Option<ReasoningEffort>,
    /// Sampling controls applied to this agent's model calls.
    pub model_settings: ModelSettings,
    /// Effective context window in tokens for this agent.
    pub context_window: Option<u32>,
    /// The prompt stack for this agent.
    pub prompts: Vec<Prompt>,
    /// Provider connection overrides keyed by model provider name.
    pub provider_connections: ProviderConnectionOverrides,
    /// Resolved MCP config sources for this agent, applied in order.
    ///
    /// Model-visible server name collisions use last-source-wins semantics. File sources
    /// can defer all of their tools for progressive discovery.
    pub mcp_config_sources: Vec<McpConfigSource>,
    /// How this agent can be invoked.
    pub exposure: AgentSpecExposure,
    /// Tool filter for restricting which MCP tools this agent can use.
    pub tools: ToolFilter,
}

impl AgentSpec {
    /// Create a bare no-mode spec without catalog defaults or runtime policy.
    /// Production callers should prefer their catalog's `default_spec` API.
    pub fn bare(model: &LlmModel, reasoning_effort: Option<ReasoningEffort>, prompts: Vec<Prompt>) -> Self {
        Self {
            name: "__default__".to_string(),
            description: "Default agent".to_string(),
            model: model.to_string(),
            reasoning_effort,
            model_settings: ModelSettings::default(),
            context_window: None,
            prompts,
            provider_connections: ProviderConnectionOverrides::default(),
            mcp_config_sources: Vec::new(),
            exposure: AgentSpecExposure::none(),
            tools: ToolFilter::default(),
        }
    }
}

/// Defines how an agent can be invoked.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
pub struct AgentSpecExposure {
    /// Whether this agent can be invoked by users (e.g., as an ACP mode).
    pub user_invocable: bool,
    /// Whether this agent can be invoked by other agents (e.g., as a sub-agent).
    pub agent_invocable: bool,
}

impl AgentSpecExposure {
    /// Create an exposure that is neither user nor agent invocable.
    ///
    /// Used internally for synthesized default specs (e.g., no-mode sessions).
    /// Not intended for authored agent definitions — all authored agents must
    /// have at least one invocation surface.
    pub fn none() -> Self {
        Self { user_invocable: false, agent_invocable: false }
    }

    /// Create an exposure that is only user invocable.
    pub fn user_only() -> Self {
        Self { user_invocable: true, agent_invocable: false }
    }

    /// Create an exposure that is only agent invocable.
    pub fn agent_only() -> Self {
        Self { user_invocable: false, agent_invocable: true }
    }

    /// Create an exposure that is both user and agent invocable.
    pub fn both() -> Self {
        Self { user_invocable: true, agent_invocable: true }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use llm::{ToolAnnotations, ToolDefinition};
    use mcp_utils::client::{ToolAnnotationMatcher, ToolMatcher};

    #[test]
    fn default_spec_has_expected_fields() {
        let model: LlmModel = "anthropic:claude-sonnet-4-5".parse().unwrap();
        let prompts = vec![Prompt::file(PathBuf::from("/tmp/BASE.md"), PathBuf::from("/tmp"))];
        let spec = AgentSpec::bare(&model, None, prompts.clone());

        assert_eq!(spec.name, "__default__");
        assert_eq!(spec.description, "Default agent");
        assert_eq!(spec.model, model.to_string());
        assert!(spec.reasoning_effort.is_none());
        assert_eq!(spec.prompts.len(), 1);
        assert!(spec.mcp_config_sources.is_empty());
        assert_eq!(spec.exposure, AgentSpecExposure::none());
    }

    fn make_tool(name: &str) -> ToolDefinition {
        ToolDefinition::new(name, "", serde_json::json!({}))
    }

    fn make_annotated_tool(name: &str, annotations: ToolAnnotations) -> ToolDefinition {
        ToolDefinition::new(name, "", serde_json::json!({})).with_annotations(annotations)
    }

    #[test]
    fn empty_filter_allows_all_tools() {
        let filter = ToolFilter::default();
        let tools = vec![make_tool("bash"), make_tool("read_file")];
        let result = filter.apply(tools);
        assert_eq!(result.len(), 2);
    }

    #[test]
    fn allow_keeps_only_matching_tools() {
        let filter =
            ToolFilter { allow: vec![ToolMatcher::name("read_file"), ToolMatcher::name("grep")], deny: vec![] };
        let tools = vec![make_tool("bash"), make_tool("read_file"), make_tool("grep")];
        let result = filter.apply(tools);
        let names: Vec<_> = result.iter().map(|t| t.name.as_str()).collect();
        assert_eq!(names, vec!["read_file", "grep"]);
    }

    #[test]
    fn deny_removes_matching_tools() {
        let filter = ToolFilter { allow: vec![], deny: vec![ToolMatcher::name("bash")] };
        let tools = vec![make_tool("bash"), make_tool("read_file")];
        let result = filter.apply(tools);
        let names: Vec<_> = result.iter().map(|t| t.name.as_str()).collect();
        assert_eq!(names, vec!["read_file"]);
    }

    #[test]
    fn wildcard_matching() {
        let filter = ToolFilter { allow: vec![ToolMatcher::name("coding__*")], deny: vec![] };
        let tools = vec![make_tool("coding__grep"), make_tool("coding__read_file"), make_tool("plugins__bash")];
        let result = filter.apply(tools);
        let names: Vec<_> = result.iter().map(|t| t.name.as_str()).collect();
        assert_eq!(names, vec!["coding__grep", "coding__read_file"]);
    }

    #[test]
    fn combined_allow_and_deny() {
        let filter = ToolFilter {
            allow: vec![ToolMatcher::name("coding__*")],
            deny: vec![ToolMatcher::name("coding__write_file")],
        };
        let tools = vec![
            make_tool("coding__grep"),
            make_tool("coding__write_file"),
            make_tool("coding__read_file"),
            make_tool("plugins__bash"),
        ];
        let result = filter.apply(tools);
        let names: Vec<_> = result.iter().map(|t| t.name.as_str()).collect();
        assert_eq!(names, vec!["coding__grep", "coding__read_file"]);
    }

    #[test]
    fn annotation_allow_matches_present_values() {
        let filter = ToolFilter { allow: vec![ToolMatcher::read_only()], deny: vec![] };
        let tools = vec![
            make_tool("unknown"),
            make_annotated_tool("read", ToolAnnotations { read_only_hint: Some(true), ..ToolAnnotations::default() }),
            make_annotated_tool("write", ToolAnnotations { read_only_hint: Some(false), ..ToolAnnotations::default() }),
        ];
        let names: Vec<_> = filter.apply(tools).into_iter().map(|tool| tool.name).collect();
        assert_eq!(names, vec!["read"]);
    }

    #[test]
    fn deny_annotation_removes_destructive_tools() {
        let filter = ToolFilter {
            allow: vec![],
            deny: vec![ToolMatcher::annotations(ToolAnnotationMatcher {
                destructive: Some(true),
                ..ToolAnnotationMatcher::default()
            })],
        };
        let tools = vec![
            make_tool("unknown"),
            make_annotated_tool(
                "safe_update",
                ToolAnnotations {
                    read_only_hint: Some(false),
                    destructive_hint: Some(false),
                    ..ToolAnnotations::default()
                },
            ),
        ];
        let names: Vec<_> = filter.apply(tools).into_iter().map(|tool| tool.name).collect();
        assert_eq!(names, vec!["unknown", "safe_update"]);
    }

    #[test]
    fn annotation_matchers_do_not_match_missing_fields() {
        let filter = ToolFilter {
            allow: vec![],
            deny: vec![
                ToolMatcher::annotations(ToolAnnotationMatcher {
                    destructive: Some(true),
                    ..ToolAnnotationMatcher::default()
                }),
                ToolMatcher::annotations(ToolAnnotationMatcher {
                    open_world: Some(true),
                    ..ToolAnnotationMatcher::default()
                }),
                ToolMatcher::annotations(ToolAnnotationMatcher {
                    idempotent: Some(false),
                    ..ToolAnnotationMatcher::default()
                }),
                ToolMatcher::annotations(ToolAnnotationMatcher {
                    read_only: Some(false),
                    ..ToolAnnotationMatcher::default()
                }),
            ],
        };
        let tools = vec![make_tool("unknown")];
        let names: Vec<_> = filter.apply(tools).into_iter().map(|tool| tool.name).collect();
        assert_eq!(names, vec!["unknown"]);
    }

    #[test]
    fn annotation_matchers_do_not_infer_fields_from_read_only_hint() {
        let filter = ToolFilter {
            allow: vec![ToolMatcher::annotations(ToolAnnotationMatcher {
                destructive: Some(false),
                ..ToolAnnotationMatcher::default()
            })],
            deny: vec![],
        };
        let tools = vec![make_annotated_tool("read", ToolAnnotations::read_only())];
        assert!(filter.apply(tools).is_empty());
    }

    #[test]
    fn deny_wins_over_allow() {
        let filter =
            ToolFilter { allow: vec![ToolMatcher::read_only()], deny: vec![ToolMatcher::name("coding__read_file")] };
        let tools = vec![make_annotated_tool(
            "coding__read_file",
            ToolAnnotations { read_only_hint: Some(true), ..ToolAnnotations::default() },
        )];
        assert!(filter.apply(tools).is_empty());
    }

    #[test]
    fn mixed_allow_entries_are_ored() {
        let filter = ToolFilter { allow: vec![ToolMatcher::read_only(), ToolMatcher::name("plan__*")], deny: vec![] };
        let tools = vec![
            make_annotated_tool(
                "coding__grep",
                ToolAnnotations { read_only_hint: Some(true), ..ToolAnnotations::default() },
            ),
            make_tool("plan__write_plan"),
            make_tool("coding__bash"),
        ];
        let names: Vec<_> = filter.apply(tools).into_iter().map(|tool| tool.name).collect();
        assert_eq!(names, vec!["coding__grep", "plan__write_plan"]);
    }

    #[test]
    fn empty_annotation_matcher_matches_nothing() {
        let filter =
            ToolFilter { allow: vec![ToolMatcher::annotations(ToolAnnotationMatcher::default())], deny: vec![] };
        let tools = vec![make_annotated_tool(
            "coding__grep",
            ToolAnnotations { read_only_hint: Some(true), ..ToolAnnotations::default() },
        )];
        assert!(filter.apply(tools).is_empty());
    }

    #[test]
    fn exact_name_match_is_not_a_prefix_match() {
        let filter = ToolFilter { allow: vec![ToolMatcher::name("bash")], deny: vec![] };
        let names: Vec<_> =
            filter.apply(vec![make_tool("bash"), make_tool("bash_extended")]).into_iter().map(|t| t.name).collect();
        assert_eq!(names, vec!["bash"]);
    }

    #[test]
    fn tool_matcher_uses_exact_and_trailing_wildcard_names() {
        let exact = ToolMatcher::name("foo");
        let wildcard = ToolMatcher::name("foo*");
        assert!(exact.matches(&make_tool("foo")));
        assert!(!exact.matches(&make_tool("foobar")));
        assert!(wildcard.matches(&make_tool("foobar")));
        assert!(wildcard.matches(&make_tool("foo")));
        assert!(!wildcard.matches(&make_tool("bar")));
    }
}