v1.108.174 — an empty index says so

An empty index says so.

Raised in correspondence on #375. A user ran the suite for months with jdatamunch holding zero datasets and jdocmunch holding three documents, and only discovered it by going looking.

Their framing of the class is the part worth keeping: every tool answers confidently regardless of how little it holds, so an agent cannot tell "I searched everything and it is not there" from "I have almost nothing indexed". That single ambiguity is what cost them a wrong-path hour.

list_repos on an empty store now carries top-level empty: true plus a hint naming index_folder and saying why it matters, so an empty search is not read as evidence of absence.

Top-level rather than under _meta deliberately: jdoc and jdata strip _meta by default, so a nudge placed there would be deleted before the agent ever saw it. Identical key names across all three servers, so this is one contract rather than three.

Deliberately NOT attempting the "under-indexed" case. Zero indexed repositories is a fact; "too few" is an inference, and any threshold would manufacture false warnings on small repos. Only the unambiguous case ships.

Additive and silent once anything is indexed: no key, no token, no behavior change. No schema, tool-count, or INDEX_VERSION change.

Suite parity: jdatamunch-mcp v1.28.0 ships the same nudge.