Remote full-field search

sd search TERM retains its title-only default. Explicit --full additionally matches identifiers, descriptions and valid comments, with the same filters, closed-item counts, sorting and pagination as the snapshot implementation.

For current remote reads, the server must support the explicit substring-index contract and have a complete compatible index. A cheap readiness request precedes text selection. Each subsequent request requires the same contract; a missing acknowledgement or unavailable index refuses rather than materializing a board snapshot. No positive or negative readiness result is cached between searches. Terms shorter than three Unicode characters after lowercasing, or containing NUL, refuse before query evaluation because this index cannot accelerate them. Default title-only searches retain support for short terms.

The backend projects matching subjects before joining compact metadata, validates comment parents and integer positions, and deduplicates matching comment parents before item eligibility checks. Main and ephemeral graphs retain their effective shadowing rules. Only the selected page’s item bodies are hydrated.

An operator must explicitly prepare the optional index using the matching Quipu maintenance tooling. A source update does not authorize production backfill. Dropping it makes requiring searches refuse; ordinary title searches retain their existing contract. Historical reads retain the existing snapshot read-cost gate.

The public synthetic demo and protocol contract live in Quipu’s docs/probes/pr-demos/substring-search/ and docs/book/src/reference/substring-search.md.