ctx-kb-ground

name	ctx-kb-ground
description	Read-only freshness audit over the kb's tracked sources (URLs, in-tree paths, MCP resources) declared in grounding-sources.md. Classifies each source's drift state, annotates the source-coverage ledger, and writes a ground closeout; flags drifted or new-to-kb sources for /ctx-kb-ingest. Never mints evidence, authors prose, or transitions ledger states.

Walk the sources declared in .context/ingest/grounding-sources.md and report whether the kb's claims are still current. This is the "are we still current?" pass — a read-only freshness audit, not a re-ingest.

Each tracked source — URLs, in-tree paths, or MCP resources — gets resolved and classified as unchanged, drifted, gone, freshness opaque, or new to kb. The skill annotates the source-coverage ledger's Residue / Next action cells and writes a ground closeout. It does NOT mint EV-### rows, author topic-page prose, transition ledger states, or modify Confidence bands; those are /ctx-kb-ingest's authority.

If a tracked source drifted or is new to the kb, flag it and recommend a follow-up /ctx-kb-ingest. The declarative watch list in grounding-sources.md persists across sessions and tracks sources from anywhere the kb cites — the web, this repo's tree, an MCP server. Distance from the repo is irrelevant; what matters is that the kb depends on them for evidence.

When to Use

• The user says "re-ground the kb", "check upstream", "refresh sources".
• A grounding cadence is hitting its scheduled boundary.
• A prior pass left a Q-### row that names "needs re-grounding".

When NOT to Use

• The user has new sources to add (/ctx-kb-ingest).
• The user asks a question (/ctx-kb-ask).
• The user wants a mechanical audit (/ctx-kb-site-review).

Input

No positional arg. Sources come from .context/ingest/grounding-sources.md (one source per line; NONE on a line is a per-pass skip).

Pre-Write Gates

• .context/ missing → suggest ctx init and stop.
• .context/ingest/ missing → suggest ctx init --upgrade and stop.
• grounding-sources.md missing or empty → prompt the user once for sources to add; if they decline, write a ground closeout with sources: 0 and stop.

Process

1. Verify pre-write gates.
2. Read .context/ingest/grounding-sources.md. For each non-skipped line, fetch / re-read the source and compare against evidence-index.md rows already citing it.
3. Update the source-coverage ledger row for each source touched: partially-ingested → partially-ingested (touched), comprehensive → comprehensive (if no drift detected), or flag drift in the closeout.
4. For each source that surfaces material the kb should absorb, flag it and recommend a follow-up /ctx-kb-ingest invocation in the closeout's Next pass hint.
5. Write the ground closeout under .context/ingest/closeouts/<TS>-ground-closeout.md with required frontmatter (sha, branch, mode: ground, pass-mode: n/a, life-stage, generated-at) and a body listing each source touched, its drift verdict, and any Next pass hint.

Anti-Patterns

• Authoring topic-page prose from refresh output. Authoring is /ctx-kb-ingest's authority.
• Minting EV-### rows. Evidence minting is ingest's authority.
• Promoting confidence bands without contradicting evidence. Drift detection alone is not promotion.
• Skipping the closeout. Even a no-op refresh writes one so the ledger advance is auditable.