Analyzing change impact with karmaIQ

Analyzing change impact with karmaIQ

The user is in (or about to enter) code that may have production callers. Before they refactor, rename, delete, or modify, surface the blast radius.

Decide: subagent or inline

Delegate to karmaiq-impact-analyzer subagent (preferred for multi-target). Use the Task tool with subagent_type=karmaiq-impact-analyzer whenever:

• The user is renaming/deleting/refactoring 2+ methods or a class
• A pre-commit hook injected a list of changed methods to check
• The user asked about service-level change ("can we replace X service")
• The investigation requires graph + code-path correlation

Pass the targets verbatim. Subagent returns a ranked dependents table per target.

Stay inline only when:

• Single method or single service
• User already has the exact node_id or method hash
• User explicitly asks to keep it in the main chat

Inline workflow

For a method

1. search_catalog(catalog="service", class_names=[<class>])   # → service_name
2. analyze_code_path_impact(service_name=<resolved>, query="<Class.method>", include_flows=true)
3. Render: direct callers, transitive callers, amplification flags, top affected flows

For a service

1. search_catalog(catalog="graph", query="<service>")   # → node_id
2. simulate_failure(node_id=<resolved>, detail="summary")   # ranked blast counts
3. simulate_failure(node_id=<resolved>, detail="full", top_k=20)   # ranked QPM-lost
4. Render: top 5 affected interfaces, total QPM impact, amplification flags >2×

For "what depends on X"

• API/service: traverse_dependencies(direction="upstream")
• Method: explore_code_path(direction="callers")

Read the active domain from ${CLAUDE_PLUGIN_DATA}/../karmaiq-core/domain.txt. Pass domain=... on every call.

Output template

## Finding
<is it safe / risky / load-bearing — 1 line>

## Evidence
<table of top dependents with QPM, amplification, and risk classification>

## Next step
<one concrete action: review the top caller, add a deprecation, or proceed safely>

Risk classification

Class	Criteria
LOW	<50 QPM total dependent traffic, no amplification > 2×
MED	50–500 QPM OR amplification 2–4× on any edge
HIGH	>500 QPM OR amplification > 4× OR appears in any critical path

Hard rules

1. Never assume a method is unused based on absence of callers in the file you're reading. Always confirm via explore_code_path(direction="callers") first.
2. Preserve method names, class names, and service names byte-for-byte. The system does exact string match.
3. If search_catalog(catalog="service") returns multiple owning services, ask the user to clarify rather than guessing.
4. Read active domain from ${CLAUDE_PLUGIN_DATA}/../karmaiq-core/domain.txt. If unset, tell user to run /karmaiq-core:setup and stop.

Forbidden

• Mutating anything (this plugin is read-only)
• Calling simulate_failure with failure_type="errors" as a substitute for regression_diff — different tool, different purpose
• Using code-path tools to ask about latency (no latency at the code layer)
• Recommending a change as "safe" without showing the evidence table