Every other check in doctor is about symlink paths. That is the wrong shape
for Claude Code, which has no symlinks — it has the plugin, and it gates
updates on plugin.json's version. A host that never picked up a release loads
every skill successfully and is simply a generation behind, silently.
Found live while writing this: koala had skills@mathias 0.6.0 installed, a
marketplace clone at 0.7.0 and a checkout at 0.8.4, and doctor said "clean".
doctor now compares the version recorded in installed_plugins.json against the
newest manifest already on the host — the active checkout and any marketplace
clone, filtered to plugin.json files that actually name this plugin — and fails
naming both versions. Offline, like the rest of doctor: "available" never means
a fetch.
A host with no install record is a valid symlink-only configuration and stays
clean. --json grows a "plugin":{"installed","available"} object so per-host
results can be collected without parsing prose.
Four new fixture cases: match, stale, absent record, newer marketplace clone.
Live output on koala:
FAIL plugin-version: Claude Code has skills@mathias 0.6.0 installed but
0.8.4 is available on this host
Closes #30
Bump-Type: minor