Skill System

Architectural Layer: L2 Skills
Source Directory: src/skill
File Count: 6 source files

Modular skill discovery, invocation, and in-task execution guidance.

Module Files & Detailed Reference

Source File	Lines	Key Types	Responsibility
compiler.rs	285	CompiledSubDag, CompiledSubTask, SkillCompiler	Dual-Mode Skill Execution Compiler (SKL-01, SKL-03, D-10). Compiles d...
discovery.rs	151	SkillDiscovery, SkillPackage, SkillOriginTier	Multi-Tier Skill Discovery (SKL-01, D-09). Scans across Builtin ->...
manifest.rs	376	PluginManifest, SkillExecutionConfig, SkillManifest	Declarative SKILL.toml Manifest Schema (SKL-01, D-09). Enforces stric...
mod.rs	17	Functions/Traits	Skills Architecture & Reusable Capabilities Engine (SKL-01, SKL-02...
registry.rs	253	SkillRegistry, SkillError	Skill Registry with Collision Resolution & Monotonic Safety Valida...
verification.rs	90	SkillVerificationCompiler, SkillVerificationPlan	Skill Verification Plan Compiler (SKL-01, SKL-03, D-12). Transforms d...

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src/skill/compiler.rs

• Source Link: src/skill/compiler.rs on GitHub
• Lines of Code: 285 (10831 bytes)

Primary Responsibility

Dual-Mode Skill Execution Compiler (SKL-01, SKL-03, D-10). Compiles declarative skills into either: 1. Sub-DAG task fragments admitted through scheduler dependency validation 2. In-task procedural prompt guidance within single-step agent contexts

Types & Trait Declarations

• Structs (3): CompiledSubDag, CompiledSubTask, SkillCompiler

Key Functions & Signatures (5 shown)

// pub
fn compile_sub_dag(manifest: &SkillManifest,
        parent_task_id: TaskId,) -> Result<CompiledSubDag, String>;
// pub
fn compile_in_task_guidance_with_catalog(manifest: &SkillManifest,
        catalog: &impl crate::prompt::catalog::Prompt;
// pub
fn compile_in_task_guidance(manifest: &SkillManifest) -> String;
// private
fn test_compile_sub_dag_generates_tasks_and_edges();
// private
fn test_compile_in_task_guidance();

Unit Verification (1 inline tests)

Tests defined within module: test_compile_sub_dag_generates_tasks_and_edges

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src/skill/discovery.rs

• Source Link: src/skill/discovery.rs on GitHub
• Lines of Code: 151 (5089 bytes)

Primary Responsibility

Multi-Tier Skill Discovery (SKL-01, D-09). Scans across Builtin -> System -> User -> Workspace precedence tiers, parses SKILL.toml files, and calculates cryptographic SHA-256 content hashes.

Types & Trait Declarations

• Structs (2): SkillDiscovery, SkillPackage
• Enums (1): SkillOriginTier

Key Functions & Signatures (5 shown)

// private
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result;
// pub
fn compute_sha256(content: &str) -> String;
// pub
fn builtin_skills() -> Vec<SkillPackage>;
// pub
fn discover_directory(base_dir: &Path, tier: SkillOriginTier) -> Vec<SkillPackage>;
// pub
fn discover_all(workspace_root: Option<&Path>) -> Vec<SkillPackage>;

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src/skill/manifest.rs

• Source Link: src/skill/manifest.rs on GitHub
• Lines of Code: 376 (11294 bytes)

Primary Responsibility

Declarative SKILL.toml Manifest Schema (SKL-01, D-09). Enforces strict schema validation, capability declaration, execution mode, procedural steps, verification commands, and risk profile.

Types & Trait Declarations

• Structs (7): PluginManifest, SkillExecutionConfig, SkillManifest, SkillProcedure, SkillRiskProfile, SkillStepDefinition, SkillVerificationSpec
• Enums (3): PluginValidationError, SkillExecutionMode, SkillRiskLevel

Key Functions & Signatures (11 shown)

// private
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result;
// private
fn from_str(s: &str) -> Result<Self, Self::Err>;
// private
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result;
// private
fn default_input_schema() -> serde_json::Value;
// pub
fn parse_toml(content: &str) -> Result<Self, String>;
// private
fn default_plugin_timeout() -> u64;
// pub
fn parse_toml(content: &str) -> Result<Self, String>;
// pub
fn validate_sandbox(&self, raw_bytes: Option<&[u8]>) -> Result<(), PluginValidationError>;
// private
fn test_parse_valid_skill_manifest();
// private
fn test_reject_unknown_fields();
// private
fn test_reject_unsupported_schema_version();

Unit Verification (3 inline tests)

Tests defined within module: test_parse_valid_skill_manifest, test_reject_unknown_fields, test_reject_unsupported_schema_version

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src/skill/mod.rs

• Source Link: src/skill/mod.rs on GitHub
• Lines of Code: 17 (706 bytes)

Primary Responsibility

Skills Architecture & Reusable Capabilities Engine (SKL-01, SKL-02, SKL-03).

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src/skill/registry.rs

• Source Link: src/skill/registry.rs on GitHub
• Lines of Code: 253 (8708 bytes)

Primary Responsibility

Skill Registry with Collision Resolution & Monotonic Safety Validation (SKL-01, SKL-03, D-09).

Types & Trait Declarations

• Structs (1): SkillRegistry
• Enums (1): SkillError

Key Functions & Signatures (10 shown)

// pub
fn new() -> Self;
// pub
fn load_discovered(workspace_root: Option<&Path>) -> Result<Self, SkillError>;
// pub
fn register(&mut self, package: SkillPackage) -> Result<(), SkillError>;
// pub
fn get(&self, id: &str) -> Option<&SkillPackage>;
// pub
fn list(&self) -> Vec<&SkillPackage>;
// pub
fn validate_agent_authority(&self,
        skill: &SkillManifest,
        agent_envelope: &HashSet<String>,) -> Result<(;
// private
fn create_dummy_package(id: &str,
        tier: SkillOriginTier,
        v_tier: u8,
        risk: SkillRiskLevel,
     ;
// private
fn test_registry_monotonic_rejection_on_lowered_tier();
// private
fn test_registry_monotonic_rejection_on_removed_approval();
// private
fn test_agent_authority_validation();

Unit Verification (3 inline tests)

Tests defined within module: test_registry_monotonic_rejection_on_lowered_tier, test_registry_monotonic_rejection_on_removed_approval, test_agent_authority_validation

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src/skill/verification.rs

• Source Link: src/skill/verification.rs on GitHub
• Lines of Code: 90 (3137 bytes)

Primary Responsibility

Skill Verification Plan Compiler (SKL-01, SKL-03, D-12). Transforms declarative SkillVerificationSpec into an executable VerificationPlan, enforcing runtime monotonicity: max(skill_tier, profile_tier, mission_tier).

Types & Trait Declarations

• Structs (2): SkillVerificationCompiler, SkillVerificationPlan

Key Functions & Signatures (3 shown)

// pub
fn compile(skill_id: &str,
        spec: &SkillVerificationSpec,
        minimum_tier: Option<CheckTier>,) -> Result<Ski;
// private
fn test_monotonic_verification_tier_strengthening();
// private
fn test_verification_plan_preserves_higher_skill_tier();

Unit Verification (2 inline tests)

Tests defined within module: test_monotonic_verification_tier_strengthening, test_verification_plan_preserves_higher_skill_tier

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