autobot-infrastructure/shared/tools/index_documentation.py is an orphaned pre-#15845 duplicate of doc_indexer.py #16956

What

autobot-infrastructure/shared/tools/index_documentation.py (927 lines) is a standalone, pre-consolidation CLI indexer -- its own argparse, its own ChromaDBIndexer class, its own hash-cache handling, its own chunking calls. It is not imported or executed by anything: a repo-wide grep for its path turns up only two historical docstring mentions (autobot-backend/services/knowledge/doc_indexer.py's own "Extracted from ..." note, and a citation in autobot_shared/doc_chunking.py), no functional references.

The doc-sync git hook resolves INDEX_SCRIPT="$PROJECT_ROOT/tools/index_documentation.py" -- the top-level tools/index_documentation.py (98 lines), added by #15845 as a thin CLI entry point that calls services.knowledge.doc_indexer.get_doc_indexer_service().index_all(). That is the actually-consolidated, actually-executed service (doc_indexer.py's own docstring: "Issue #1385: Consolidated documentation indexing... Extracted from autobot-infrastructure/shared/tools/index_documentation.py and adapted for service use").

So #1385's extraction happened, and #15845 independently gave the hook a working entry point pointing at the new service -- but nobody deleted or redirected the old standalone file it was extracted from. It has sat dead since.

Why this matters

• It is duplicate, unmaintained logic: any future indexing bug fix (e.g. bug(kb): the doc-sync commit hook re-embeds every doc into the live KB from any worktree, because its hash cache is per-checkout #16934, which fixed doc_indexer.py's per-checkout hash-cache path) has to remember this second copy exists and either fix it too or confirm it's dead, rather than there being one indexer.
• docs/developer/ or contributor searches for "how does doc indexing work" can land on either file with no signal that one is inert.

Fix

Either:

1. Delete autobot-infrastructure/shared/tools/index_documentation.py (confirm zero references first, including CI/docs/README mentions of the old path), or
2. If any residual caller is found, wire it to the consolidated doc_indexer.py service instead of duplicating logic, per Bug: Chat halluccinates instead of using knowledge base for AutoBot documentation queries #1385's own stated intent.

Option 1 is expected to be correct based on the repo-wide grep above, but re-verify before deleting -- this issue does not include that verification pass.

Found during #16934 (worktree doc-index contamination fix), out of scope for that PR.