corpus-grounding-expander

name	corpus-grounding-expander
description	Fetches and normalizes multi-version public-domain corpora into a single verified-axiom store for verbatim-relay grounding, recording per-version license and provenance.
user-invocable	true
allowed-tools	["Read","Bash","WebFetch","Write"]
model	sonnet

corpus-grounding-expander

Builds or broadens the grounded axiom a relay system quotes from. When a system's output must be constrained to verbatim source (fail-closed grounding), the corpus IS the axiom — this skill expands that corpus from multiple public-domain versions so grounding is robust and non-biased (a quote verified in ANY version counts), without ever adding a generator.

Origin: harvested from the-bible (2026-06-20) — 6 public-domain Bible versions, 197k verses, as the fail-closed grounding axiom. Generalizes to any verbatim-relay corpus (legal statute, RFC text, standards). See tracks/_contrib/field_harvest_2026-06-20_gate-locality-and-grounding-capabilities.md.

Triggers

• "get more sources" / "broaden the grounded corpus"
• "add another version of the corpus"
• "ingest the full as the grounding axiom"
• /corpus-grounding-expander {source or version}

Natural Language Triggers (example user phrases)

• "이 코퍼스 여러 버전으로 통째로 가져와줘"
• "the grounding DB is just a sample — pull the whole thing, multiple editions"
• "add a second public-domain edition so we're not biased to one"

Steps

1. Source + license check — identify the public-domain source(s) and confirm each is genuinely free to redistribute. Record the license literally (no assumption).
2. Fetch (retry-disciplined) — pull each version; on transient error, backoff-retry before declaring the source unavailable (do not silently drop a version).
3. Normalize to a single key schema — map every version to the SAME addressable key (e.g. ref → text) so cross-version quotation stays aligned. Write per-version files + an _index recording version id, license, scope, and record count.
4. Wire grounding as a union — the grounding check passes if the quote matches the canonical text at that key in ANY version. Never add a path that generates text — grounding is quote-only.
5. Relay-integrity check — confirm the consumer (the gate) QUOTES the corpus and cannot emit un-grounded text; run a fabrication probe (a known non-source quote must fail-closed).

Done When

• Each added source carries a verifiable public-domain/license record in the index. Check class: mandatory-pass (binary — license field present and non-empty per version).
• Every version is normalized to the same key schema (cross-version keys align). Check class: mandatory-pass (a shared sample key resolves in each version or is explicitly canon-scoped).
• The index declares the quote-only union contract (grounding matches verbatim text in ANY version; no generation path) and ships a fabrication-probe spec for the consumer to run. Check class: mandatory-pass (binary — quote-only contract + probe-spec present in the index).

Guards

• Grounding, never a generator — the relay constraint is structural; this skill wires grounding.
• License-literal — record the actual license per source; never assume public-domain.
• No silent version drop — a fetch failure is a named residual in the index, not a quiet omission.

Independently executable

Yes — needs only a network fetch + file write. No dependency on other FH skills (a consumer gate that reads the corpus is the system's own, not this skill's).