g3/analysis/deps/hotspots.md

Coupling Hotspots

Scope: Changes in commits b6d2582..9443f933 (10 commits)

High Fan-In Files (Most Depended Upon)

Files that many other files depend on. Changes here have wide impact.

File	Fan-In	Dependents	Risk
g3-core/src/skills/parser.rs	3	discovery.rs, prompt.rs, mod.rs	Medium
g3-core/src/skills/embedded.rs	3	discovery.rs, extraction.rs, mod.rs	Medium
g3-core/src/skills/mod.rs	3	lib.rs, prompts.rs, project_files.rs (cross-crate)	High
g3-config/src/lib.rs	2	g3-core, g3-cli (cross-crate)	High
g3-cli/src/project_files.rs	2	lib.rs, agent_mode.rs	Medium

Analysis

g3-core/src/skills/mod.rs (Fan-In: 3, Cross-Crate: Yes)

• Re-exports Skill, discover_skills, generate_skills_prompt, EmbeddedSkill
• Used by g3-core/src/lib.rs (re-export), g3-core/src/prompts.rs, g3-cli/src/project_files.rs
• Evidence: pub use parser::Skill, pub use discovery::discover_skills
• Impact: API changes affect both g3-core internals and g3-cli

g3-core/src/skills/parser.rs (Fan-In: 3, Cross-Crate: No)

• Defines Skill struct used throughout skills module
• Evidence: use super::parser::Skill in discovery.rs, prompt.rs
• Impact: Struct field changes ripple through entire skills subsystem

g3-config/src/lib.rs (Fan-In: 2, Cross-Crate: Yes)

• Added SkillsConfig struct
• Evidence: use g3_config::SkillsConfig in project_files.rs
• Impact: Config schema changes affect CLI startup

High Fan-Out Files (Most Dependencies)

Files that depend on many others. Complex, potentially fragile.

File	Fan-Out	Dependencies	Risk
g3-core/src/skills/mod.rs	5	parser, discovery, prompt, embedded, extraction	Medium
g3-core/src/skills/discovery.rs	2	parser.rs, embedded.rs	Low
g3-cli/src/project_files.rs	2	g3-core::skills, g3-config	Medium
studio/src/main.rs	3	sdlc.rs, git.rs, session.rs	Low

Analysis

g3-core/src/skills/mod.rs (Fan-Out: 5)

• Module root that coordinates all skills submodules
• Evidence: mod parser; mod discovery; mod prompt; mod embedded; pub mod extraction
• Impact: Central coordination point, but each submodule is relatively independent

g3-cli/src/project_files.rs (Fan-Out: 2, Cross-Crate: Yes)

• Bridges g3-core skills and g3-config
• Evidence: use g3_core::{discover_skills, ...}, use g3_config::SkillsConfig
• Impact: Integration point for skills feature in CLI

Cross-Crate Coupling

Edges that cross crate boundaries. Higher coordination cost for changes.

From	To	Type	Evidence
g3-cli/src/project_files.rs	g3-core::skills	use_external	use g3_core::{discover_skills, generate_skills_prompt, Skill}
g3-cli/src/project_files.rs	g3-config	use_external	use g3_config::SkillsConfig
g3-core/src/lib.rs	g3-core::skills	pub_use	pub use skills::{Skill, discover_skills, generate_skills_prompt}

Compile-Time Coupling (include_str!)

Files embedded at compile time. Build breaks if missing.

Source	Embedded File	Evidence
g3-core/src/skills/embedded.rs	skills/research/SKILL.md	include_str!("../../../../skills/research/SKILL.md")
g3-core/src/skills/embedded.rs	skills/research/g3-research	include_str!("../../../../skills/research/g3-research")

Impact:

• Moving or renaming skills/research/ breaks g3-core compilation
• Content changes require g3-core recompilation
• Relative path ../../../../ is fragile to directory restructuring

Deleted Code Impact

Removed files and their former dependents.

Deleted File	Lines	Former Dependents
g3-core/src/pending_research.rs	540	g3-core/src/lib.rs, tools/research.rs
g3-core/src/tools/research.rs	710	tool_dispatch.rs, tools/mod.rs

Impact:

• Research functionality moved to external skill
• tool_dispatch.rs and tools/mod.rs modified to remove research tool dispatch
• CLI commands related to research removed from commands.rs

Recommendations for Monitoring

1. g3-core/src/skills/mod.rs: Watch for API surface changes
2. g3-config/src/lib.rs: Watch for SkillsConfig schema changes
3. skills/research/: Watch for path changes (compile-time dependency)
4. g3-cli/src/project_files.rs: Integration point, test after skills changes