What it means
The distribution — bin/, lib/, share/ — is not part of the repository's data. It may be a checkout under ~/tools, a package on PATH, or a copy inside the repository, and every form behaves the same because nothing writes into it. Two copies of one version, pointed at one repository, read the same files under .ai/ and produce the same findings.
How it works
lib/common.sh derives the distribution root from the entry point that was run, never from the environment, so a majordomus started under another majordomus (a git hook, finish --verify-command) reads its own share/ and not the outer one; the repository root comes from git. Every path the commands write is resolved under the repository's .ai/ or one of the projection targets the policy names, and test/cases/08_no_forbidden_constructs.sh refuses a redirect into any other path variable.
How to see it
cp -R /path/to/majordomus /tmp/dist
before=$(cd /tmp/dist && find . -type f | sort | xargs shasum -a 256 | shasum -a 256)
/tmp/dist/bin/majordomus init && /tmp/dist/bin/majordomus doctor
( cd /elsewhere && PATH=/tmp/dist/bin:$PATH majordomus --repo /path/to/repo start "task" --scope docs )
after=$(cd /tmp/dist && find . -type f | sort | xargs shasum -a 256 | shasum -a 256)
[ "$before" = "$after" ] # the distribution is byte for byte what it wasWhat it does not cover
Two different versions are allowed to disagree, and rules vendor status is how a repository learns that the executable in front of it ships a different rule package than the one it vendored. Nothing here pins a repository to a tool version.
Why it exists
A tool that writes into its own installation cannot be shared, cannot be installed read-only, and behaves differently depending on which copy ran last. test/cases/65_tool_root_independence.sh runs one version from the checkout, from an unrelated absolute path and through PATH, compares their doctor findings line by line, and hashes the distribution before and after.