From the files a change touched, the tool names the commands, rules, use cases, scenarios and behavioural cases affected, and scaffolds a draft for a capability no use case covers

A worker who changed a file does not have to remember which use cases describe it.

guaranteed Deterministic and blocking. Implemented, and a behavioural test proves it.

usecase impact maps paths through docs/RESPONSIBILITIES.yaml, the dispatch table, the rules' identities and the scenarios' fixtures; usecase scaffold writes drafts from the registry, the command fixture and the claims, and never a guarantee.

What it means

A worker who changed a file does not have to remember which use cases describe it. majordomus usecase impact reads the files changed since a base (the upstream by default) and in the work tree and names the commands, the rules, the use cases, the scenarios among them and the behavioural cases they reach, ending with the run to do. majordomus usecase scaffold writes a draft for a capability no active use case names, from what the registry, the command's fixture and the claims already know, and never marks anything guaranteed.

How it works

mj_uc_cmd_impact maps paths: lib/<command>.sh to the command, a responsibility's files and implementation (docs/RESPONSIBILITIES.yaml) to its command, a rule file to its front-matter id, a use-case file, setup script or stdin body to the use cases that use it, docs/CLAIMS.yaml to every use case naming a claim, the crate to every use case naming an MCP tool, and bin/majordomus, lib/common.sh, the registry, the manifest and the policy to every command; commands and rules then map to the use cases naming them, and to the cases whose majordomus-covers header names the command or which a rule lists under tests. mj_uc_cmd_scaffold writes <command>-draft.md with status: draft, target: advisory and a scenario taken from the command's fixture.

How to see it

majordomus usecase impact --base origin/master
majordomus usecase impact --json
majordomus usecase scaffold --missing --dry-run

What it does not cover

Impact is computed from declared relations, not from a call graph: a helper used by every command is reached only when it lives in a file the map knows (lib/common.sh reaches everything). A draft is a starting point; the narrative and the assertions are a person's or an agent's work.