impact

name	impact
description	Use before refactoring, deleting, moving, or substantially modifying a file to compute its blast radius, coupling profile, and cycle exposure. Lets the agent edit with awareness of downstream effects rather than discovering them after the fact.

Impact

Call this before a non-trivial edit (deletion, rename, signature change, extraction, file move). It tells the agent what depends on the target and what the target depends on, so the edit plan can account for the blast radius up front.

All tools take a path argument (absolute, current repo root) plus the target file path relative to that root.

Steps

1. Blast radius — call raysense_blast_radius with path: <cwd> and file: <target>. Returns the set of files reachable downstream under the active edge filter. A blast radius >20 files is a strong signal to break the change into smaller commits.
2. Coupling profile — call raysense_coupling. Look up the target's module in the response: afferent (incoming) and efferent (outgoing) counts, plus main-sequence distance. High-afferent modules are stable foundations — breaking changes there cascade widely.
3. Cycle exposure — call raysense_cycles. If the target appears in any reported cycle, call raysense_break_cycle_recommendations for ranked candidate edges to remove. The recommended edge is often not the obvious one.
4. Optional simulation — when the planned change is mechanical (file removal, edge removal), call raysense_what_if to preview the health delta without touching the working tree.

What to keep in working memory

• Number of files in the blast radius — quote it back to the user before starting an edit that exceeds 20.
• Whether the target is on any cycle — informs whether the edit is likely to introduce or break a cycle.
• The instability score — a value near 1.0 means the file is expected to depend on stable foundations, not be one.

When to skip

• Local-only edit inside one file with no signature changes (typo fix, comment, internal rename). No downstream effect, no need.
• Brand-new file. Nothing depends on it yet.

See also

For cases the typed tools above don't cover, the query skill exposes Rayfall directly via raysense_baseline_query:

• Custom reachability rules through Datalog -- declarative (reaches ?a ?b) plus a recursive arm gives the same shape as raysense_blast_radius but with a rule the agent picks at query time.
• .graph.shortest-path / .graph.k-shortest for path-aware impact ("which call paths reach this entry point") that go beyond the blast-radius set.
• Ad-hoc joins between call_edges and change_coupling / file_ownership to weight blast radius by author / commit history.