[puretensor]

Fixes the known issue carried over from #1: changing the embedder name wiped the index without --rebuild. A puremind watch left running on the old config and a fresh puremind index on the new one kept wiping each other, and each wipe meant a full re-embed.

Behaviour

Situation	Before (0.1.3)	Now
puremind index, model or embedder_revision changed	empties the index, re-embeds every note	error: the index was built with A but B is configured; nothing was changed + hint to run --rebuild, exit 2
puremind index --rebuild, model changed	probe, empty, re-embed	unchanged
puremind watch whose model differs from the index's	wipes and re-embeds	stops, exit 2, hint: restart the watch if the model changed since it started, otherwise --rebuild
Model changed, index holds no notes	takes the new model	unchanged (nothing to lose)
Search with a mismatched model	refused, says --rebuild	unchanged

The refusal comes before the probe passage, so a refused run embeds nothing.

Changes

• indexer.py: new ModelMismatch(ValueError). index_vault raises it when the model or revision changed, the index holds notes, and rebuild is not set.
• cli.py: cmd_index reports it with a --rebuild hint. cmd_watch stops on it the same way it already stops on VaultMismatch, with a restart hint. --rebuild help text updated.
• models.py: a comment at PINNED_REVISIONS. A future release that changes the pinned embedder revision now makes every existing index need --rebuild, so its release notes must say so.
• README, CHANGELOG (## 0.1.4 (unreleased)), __version__ = "0.1.4".

Validation

• pytest -q: 599 passed, 6 skipped. ruff check src tests bench (0.17.1): clean.
• Four tests that relied on the wipe now use rebuild=True and check the refusal first. New tests: the empty-index case, the CLI index refusal and recovery, and the stale-watch scenario (a watch on old-model meets an index rebuilt for new-model, stops with exit 2, and the index keeps its 3 notes). The 5 behavioural tests fail against the previous source.
• End-to-end CLI run with a stub model: index (A), then index (B) is refused with exit 2, then index --rebuild (B) rebuilds.

Not on the model-loading path, so the real-models job isn't needed for this one.

🤖 Generated with Claude Code

https://claude.ai/code/session_011zd8G1cibJoQPVbZEpVLYs