willianbswillianbs/skills/change-impact-analyzer/SKILL.md

change-impact-analyzer

Skill0 starsChanged 4 months agoMITView on GitHub

Maps blast radius of a proposed change across services, APIs, data, and clients. Use before risky merges, migrations, or multi-service work. Emits IMPACT_REPORT. Never approves ship without naming affected consumers.

2 other projects use a version of this.

Adopted by

Most recently taken up by

imohammadfaraz/claude-skills-for-product-managertheir own version, first seen Nov 1, 2026
nahisaho/MUSUBItheir own version, first seen Jan 1, 2026

Other versions2 projects use a version of this.
Word for word · 0
None found.
Edited · 0
None found.
Wrote their own version · 2
nahisaho/MUSUBI★ 74same name
imohammadfaraz/claude-skills-for-product-manager★ 19same name
How matches are found. Word for word: the exact same text. Edited: shares passages with this file (“99% same” means 99% of its five-word phrases also appear here; 10% or more counts). Their own version: similar meaning, or, weakest, the same name. We can’t tell which project had it first. Projects are counted among the 200 most-starred candidates, and mentions are links to the repository we found, up to 50 per site, so both counts are a floor.
In this repository27 other files it gives its agents.
- adr-enforcerSkill
- ai-eval-harnessSkill
- api-contract-guardianSkill
- code-reviewerSkill
- context-loaderSkill
- defect-analystSkill
- delivery-plannerSkill
- engineering-mentorSkill
- engineering-osSkill
- feature-implementerSkill
- guardrails-configuratorSkill
- incident-commanderSkill
- loop-engineerSkill
- migration-surgeonSkill
- model-routerSkill
- observability-designerSkill
- performance-auditorSkill
- postmortem-writerSkill
- pr-generatorSkill
- quality-gateSkill
- refactoring-advisorSkill
- requirements-grillSkill
- security-auditorSkill
- spec-validatorSkill
- tdd-executorSkill
- test-strategy-designerSkill
- threat-modelerSkill

The file

We split this skill into the rules it gives an agent

6 rules. About 0 are common, 6 are distinctive, and 0 are very specific to this project.

≈0
Common · estimate
Many files like this have a rule of this kind.
≈6
Distinctive · estimate
This author's own choices. Worth a look.
0
Very specific
Tied to their project's names, files or tools. Probably skip.

Common
Distinctive
Very specific

Distinctive:
Follow edges: imports, APIs, events, schemas, feature flags, config.
line 37
Distinctive:
Prefer evidence (grep, refs, contracts) over guessing.
line 42
Distinctive:
Do not implement the change.
line 43
Distinctive:
Never claim “no impact” without a search.
line 89
Distinctive:
Never ignore versioning/compat windows for public APIs.
line 90
Distinctive:
Never silently expand scope into implementing the change.
line 91

≈ “Common” is an estimate: at least 1 in 5 of the 350,495 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.

Files

SKILL.md

Purpose

Quantify who and what a change breaks or touches so planning and QG can size risk correctly.

When to Use / When NOT to Use

Use when: cross-service changes, API/schema edits, shared library bumps, migrations, large refactors, “what will this break?”.

Do not use when: typo/docs-only; pure local private helper with no exports (lite one-liner OK).

Preconditions

Diff, PR, or proposed change description plus CONTEXT_PACK (or ability to search callers/contracts).

Inputs / Outputs

Inputs: change set / plan, CONTEXT_PACK, OpenAPI/proto/schema if present, TASK_GRAPH optional.

Outputs: IMPACT_REPORT

Upstream / Downstream

Upstream: delivery-planner, feature-implementer, api-contract-guardian, engineering-os.

Downstream: delivery-planner, test-strategy-designer, quality-gate, migration-surgeon, pr-generator.

Core Principles

Follow edges: imports, APIs, events, schemas, feature flags, config.
Name concrete consumers (services, packages, mobile/web).
Separate breaking vs compatible vs unknown.
Data/migration impact is first-class.
Unknown consumers → ProceedWithConditions or Block for public APIs.
Prefer evidence (grep, refs, contracts) over guessing.
Do not implement the change.

Process

Summarize the change intent.
Identify exported surfaces touched (HTTP, RPC, events, DB, packages).
Trace inbound/outbound dependents in-repo; note external unknowns.
Classify impact per consumer: None | Compatible | Breaking | Unknown.
Runtime/ops impact — deploy order, flags, dual-write, cache.
Test/rollout recommendations.
Decision for planner/QG.

Evidence Requirements

Cite paths, symbol names, contract files. Mark Unknown explicitly.

Stop Conditions / Failure Modes

Condition	Action
Public API change with Unknown consumers	Block or ProceedWithConditions + required discovery
Cannot access codebase	Refuse

Severity + Confidence

Breaking public contract without migration path → High/Critical.

Output Contract

## IMPACT_REPORT
Change summary: ...
Surfaces touched: ...
Consumers:
  - name, impact class, evidence
Deploy/order notes: ...
Unknowns: ...
Decision: Proceed | ProceedWithConditions | Revise | Block

Handoffs

api-contract-guardian, migration-surgeon, delivery-planner, test-strategy-designer, quality-gate.

Never

Never claim “no impact” without a search.
Never ignore versioning/compat windows for public APIs.
Never silently expand scope into implementing the change.

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