Citation Cross-Check (conditionally double-blind bib-vs-web field audit)

Codex mirror adaptation (normative). This skill has no cross-model jury by design — it is an evidence instrument, not an acquittal step (see the acceptance-gate note in Step 2, and pair it with citation-audit for the cross-model verdict). A and B are read-only extraction shards and C emits a mechanical per-field delta, so every verdict is assigned by the main agent from that delta plus its own primary-source fetch — not by any shard and not by a reviewer model.

Blindness is NOT automatically identical across hosts — it is conditional on isolation, and the gate enforces that. The whole cross-check rests on B never seeing the .bib. On the mainline, the Agent tool gives B a fresh context. On a Codex host the frontmatter grants no delegation tool (no Agent, no spawn_agent — see allowed-tools), so:

• If the host can dispatch B in a genuinely isolated context that does not inherit the main agent's history (which has already read the .bib in Step 1) — passing B only the title+first-author list — B may set blind:true and the run certifies normally.
• Otherwise (B would run in the main context, or "fresh sequential context" cannot be guaranteed to drop the parent's .bib view), B MUST set blind:false. The Step-3.5 gate then downgrades every MATCH/MINOR to ESCALATE: the run still flags discrepancies for the main agent's Step-4 webcheck, but it certifies nothing. It is a labelled heuristic, not a double-blind certification.

So the mirror never claims blindness it cannot deliver: it either has real isolation and attests it, or it declares blind:false and drops to flag-only. Do not add a spawn_agent-based reviewer/continuation route — the trust decision is the main agent's WebFetch, and it must not be delegated to a shard.

🔒 Do not wrap this skill in /loop, /schedule, or CronCreate. It is verdict-bearing — it emits a per-reference verdict that gates .bib edits (an evidence instrument, not a cross-model acquittal; see the acceptance-gate note in Step 2). Re-running it on a timer adds no signal (the verdict changes only when the bibliography changes). Schedule the external wait that precedes it: bibliography finalized → run once. See ../shared-references/external-cadence.md.

Why this exists (and how it differs from citation-audit)

citation-audit is a single cross-model reviewer that judges three things holistically: existence, metadata, and context-fit (is the cited paper used for a claim it actually supports?). This skill does not do context-fit. It does one thing that a single reviewer cannot do reliably: an adversarial, field-level diff (double-blind when the host can isolate the web agent, a labelled flag-only heuristic otherwise) of the local .bib entry against an independently reconstructed record.

The failure mode it targets is the hand-entry error that survives a plausibility read: a dropped or re-ordered author, a wrong year, a swapped venue, a DOI that 404s. A single reviewer that sees the .bib entry tends to anchor on it and rate it "looks correct." Two agents that never see each other's output cannot anchor — a discrepancy only survives if both independent records agree, and the verifier reports exactly where they diverge.

In practice it catches dropped/re-ordered authors, wrong years, and bad DOIs that a single-pass audit rated "looks clean" — while NEEDS_WEBCHECK stops it from false-flagging a legitimate non-arXiv (blog / tech-report) citation as fabricated. Use it in addition to citation-audit, not instead: citation-audit protects your review score (context-fit); this protects against the integrity red flag of a wrong or fabricated reference (existence + fields).

Constants

• BLIND = conditional — the web agent (B) MUST be prompted with only each paper's title + first author, plus its opaque dedup_key (a run-local ordinal that carries no bibliographic content), and MUST NOT read the .bib or any repo file. B attests blind:true only when the host isolates its context so it cannot inherit the .bib (see the mirror-adaptation note above); otherwise B attests blind:false and the Step-3.5 gate certifies nothing (flag-only). Do not relax the prompt restriction, and never assert blind:true without real isolation — an un-isolated blind:true is the one thing that defeats the whole cross-check.
• SOURCES = arXiv (/abs/<id>, /bibtex/<id>), DBLP, CrossRef, ACL Anthology, NeurIPS/PMLR proceedings, OpenReview. Report what the fetched page shows; never fabricate a field.
• VERDICTS (assigned by the main agent only, in Step 4 — never by a shard) = MATCH (bibliographically equivalent, cosmetic-only) / MINOR (formatting or a preprint-vs-published venue, no correction required) / MISMATCH (real discrepancy: wrong/missing author, wrong year, wrong venue, wrong id) / NEEDS_WEBCHECK (B could not confirm existence, but the entry is a @misc/blog/tech-report whose url B's index-based search structurally cannot see — the main agent must fetch that url in Step 4 before any verdict; never downgrade such an entry straight to MISMATCH).
• SCOPE = cited-only by default (entries that render in the .bbl); --all also covers uncited .bib entries.
• OUTPUT = <paper-dir>/citation_crosscheck_<date>.xlsx (+ the four intermediate JSONs — cx_A_ourbib, cx_B_web, cx_C_fielddiff, and the gate's cx_gate.json — kept for audit).

Workflow

Step 1 — Resolve the citation set (deterministic, main agent)

# Search the paper's own source tree, not the whole repo: bundled author-kit /
# template .tex carry demo \cite{...} that inflate the set. Set PAPER_DIR to the dir of
# the main .tex (\documentclass + \bibliography); recurse (cites often live in
# sections/*.tex); exclude vendored/example dirs.
PAPER_DIR="<dir of the paper's main .tex>"
cd "$PAPER_DIR"
python3 - <<'PY'
import re, pathlib
# Skip vendored/example/template trees: bundled author kits carry demo \cite{...}.
# NOTE: this is a NAME match — a dir you *want* audited must not match (rename it or
# narrow SKIP), e.g. `examples_of_results/` would be skipped.
SKIP = re.compile(r'(?i)(^|/)(.*template.*|.*upstream.*|.*example.*|.*vendor.*)(/|$)')
# Verbatim-ish blocks AND inline \verb|...| / \lstinline are code samples, not citations.
VERB = re.compile(r'\\begin\{(verbatim|lstlisting|minted|Verbatim)\}.*?\\end\{\1\}', re.S)
# The optional arg may itself contain brackets: \lstinline[language={[LaTeX]TeX}]|...|
VERBINLINE = re.compile(r'\\(?:verb|lstinline)\*?'
                        r'(?:\[(?:[^\[\]]|\[[^\]]*\])*\])?\s*'
                        r'([^\sA-Za-z])(?:(?!\1).)*\1', re.S)
# url/href/path args may contain a literal % that is NOT a comment. Neutralize them
# BEFORE comment-stripping, or a real \cite later on that line is silently lost.
URLCMD = re.compile(r'\\(?:url|href|path|nolinkurl)\s*\{[^{}]*\}')
COMMENT = re.compile(r'(?m)(?<!\\)%.*$')
# EXPLICIT ALLOWLIST of cite commands. Do NOT build this from a prefix/suffix pattern:
# a Cartesian `(no|paren|auto|...)?cite(s|p|t|...)?` both invents commands (\citecite,
# \parenciteyear -> fake keys from any brace arg) and misses real ones (\footfullcite,
# \volcite, \notecite). Longest-first so \footfullcite wins over \footcite.
# volcite-family: the FIRST brace arg is a volume/page, NOT a cite key.
VOLCITE = {'volcite', 'Volcite', 'pvolcite', 'Pvolcite', 'fvolcite', 'ftvolcite',
           'svolcite', 'tvolcite', 'avolcite',
           'volcites', 'Volcites', 'pvolcites', 'Pvolcites', 'fvolcites', 'svolcites',
           'tvolcites', 'avolcites', 'ftvolcite', 'ftvolcites'}
NAMES = sorted({
    # natbib / LaTeX core (capitalized variants are real natbib commands)
    'cite', 'Cite', 'citep', 'citet', 'citealp', 'citealt', 'citenum', 'citeyear', 'citeyearpar',
    'citeauthor', 'citefullauthor', 'Citep', 'Citet', 'Citealp', 'Citealt', 'Citeauthor',
    # biblatex singular + plural
    'parencite', 'Parencite', 'footcite', 'footcitetext', 'footcitetexts', 'textcite',
    'Textcite', 'smartcite', 'Smartcite', 'supercite', 'autocite', 'Autocite', 'fullcite',
    'footfullcite', 'notecite', 'Notecite', 'pnotecite', 'Pnotecite', 'fnotecite',
    'citetitle', 'citeurl', 'citedate', 'autocites', 'parencites', 'textcites',
    'smartcites', 'supercites', 'footcites', 'cites', 'Cites', 'nocite', 'nocites',
    # aliases + field/list forms + bibentry — real biblatex/natbib families
    'citetalias', 'citepalias', 'Citetalias', 'Citepalias', 'citefield', 'citelist',
    'bibentry', 'fullciter',
    *VOLCITE,
}, key=len, reverse=True)
# (?![A-Za-z]) stops \cite matching the \citeXYZ of an unknown command; the trailing run
# accepts any mix of [opt] and {grp} so \cites{k1}[note]{k2} yields BOTH keys.
CITE = re.compile(r'\\(?:' + '|'.join(map(re.escape, NAMES)) + r')\*?(?![A-Za-z])'
                  r'((?:\s*(?:\[[^\]]*\]|\{(?:[^{}]|\{[^{}]*\})*\}))+)', re.S)
# Strip [optional] args BEFORE reading brace groups, or a braced note like
# \cite[see {Smith} p.3]{k} contributes 'Smith' as a phantom key.
OPTARG = re.compile(r'\[[^\]]*\]', re.S)
GROUP = re.compile(r'\{((?:[^{}]|\{[^{}]*\})*)\}', re.S)
CMDNAME = re.compile(r'\\([A-Za-z]+)')
# \addbibresource[opts]{x.bib} takes an optional arg; \bibliography{a,b} may list several.
BIBRES = re.compile(r'\\(?:bibliography|addbibresource)\s*(?:\[[^\]]*\])?\{([^}]+)\}')
keys, bibs, nocite_all = set(), [], False
for p in sorted(pathlib.Path('.').rglob('*.tex')):
    if SKIP.search(str(p.parent)):
        continue
    src = p.read_text(errors='replace')
    src = VERB.sub(' ', src)
    src = VERBINLINE.sub(' ', src)
    src = URLCMD.sub(' ', src)
    src = COMMENT.sub('', src)
    for res in BIBRES.findall(src):
        bibs += [r.strip() for r in res.split(',') if r.strip()]
    for m in CITE.finditer(src):
        raw_cmd = CMDNAME.match(m.group(0)).group(1)
        cmd = raw_cmd.lower()
        grps = GROUP.findall(OPTARG.sub(' ', m.group(1)))
        if raw_cmd in VOLCITE and len(grps) > 1:
            # volcite takes {volume}{key}; the PLURAL volcites alternates
            # {vol}{key}{vol}{key}... — so keep the odd-indexed args, not just grps[1:],
            # or the second volume number is harvested as a phantom key.
            grps = grps[1::2]
        elif raw_cmd in ('citefield', 'Citefield', 'citelist', 'Citelist',
                          'bibentry') and len(grps) > 1:
            # These commands take a single key(s) arg. If a stray second brace group
            # follows (a defensive read of an ambiguous source), do not harvest it as a
            # phantom key ('\citelist{k}{publisher}' -> just 'k', not '{k, publisher}').
            grps = grps[:1]
        for grp in grps:
            toks = [''.join(g.split()) for g in grp.split(',')]
            # \nocite{*} AND \nocite{*,named}: the wildcard renders EVERY bib entry.
            if cmd.startswith('nocite') and '*' in toks:
                nocite_all = True      # see the NOCITE_ALL note below
            for k in toks:
                if k and k != '*':
                    keys.add(k)
print(f"BIB_RESOURCE={bibs[0] if bibs else '(none found - use the fallback below)'}")
print(f"BIB_RESOURCES_ALL={bibs}")
print(f"NOCITE_ALL={nocite_all}")
print(f"CITED_KEY_COUNT={len(keys)}")
import pathlib
# Persist the harvest so the shell can read it back deterministically (the heredoc only
# PRINTS to stdout; it cannot set a parent-shell variable).
pathlib.Path('/tmp/cx_cited_keys.txt').write_text('\n'.join(sorted(keys)))
pathlib.Path('/tmp/cx_cited_count.txt').write_text(str(len(keys)))
print('\n'.join(sorted(keys)))
PY
# Set $CITED_KEY_COUNT as a REAL shell variable (Step 3.5 passes it as --expect): the
# heredoc above only prints it, so read it back from the file the harvest just wrote.
CITED_KEY_COUNT=$(cat /tmp/cx_cited_count.txt)

Cross-check against a compiled main.bbl by KEY SET, not count: a count match with a substituted key still hides a harvest miss (drop one real cite, gain one stray → same count). Extract the rendered keys and diff the sets:

# \bibitem[label]{key} (natbib/plain) OR \entry{key}{type}{} (biblatex) — key is the first
# brace group either way. Empty diff = harvest and .bbl agree.
grep -oE '\\(bibitem|entry)\*?(\[[^]]*\])?\{[^}]+\}' main.bbl 2>/dev/null \
  | sed -E 's/.*\{([^}]+)\}$/\1/' | sort -u > /tmp/cx_bbl_keys.txt
comm -3 <(sort -u /tmp/cx_cited_keys.txt) /tmp/cx_bbl_keys.txt   # any output ⇒ investigate

The .bbl cross-check is conditional — an uncompiled submission has none. When absent, confirm CITED_KEY_COUNT is plausible for the paper's length before proceeding; the Step-3.5 manifest is the load-bearing coverage guard either way.

If NOCITE_ALL=True the .tex harvest is NOT the citation set. \nocite{*} renders every entry in the .bib, so under the default cited-only SCOPE the set becomes all entries that render: take the keys from the compiled .bbl when one exists, else from the .bib itself (equivalent to --all), and say so in the report. Do not proceed on the \cite-only harvest — it under-audits by exactly the uncited entries.

BIB_RESOURCES_ALL lists every \bibliography/\addbibresource found, in sorted-path order; BIB_RESOURCE is just the first. If the list has more than one entry, pick the one the main .tex declares rather than trusting the ordering, and audit the union only if the paper really loads several. If BIB_RESOURCE comes back empty (e.g. a \input-flattened submission), fall back to the largest *.bib under the paper dir and, when a compiled main.bbl exists, read the cited keys from its \bibitem{...} entries instead of the .tex (the .bbl is the ground truth for what actually rendered).

Produce the ordered list of cited keys and, for each, its title + first author (the only thing agent B is allowed to see). Confirm every key exists in the .bib. Assign each entry a stable opaque ordinal dedup_key (01, 02, … in resolved order): this is the canonical id that joins the shards downstream. A receives dedup_key + the cite key; B receives dedup_key + title + first author only (never the cite key or .bib text), so the join key never leaks the blind side. Write two artifacts for the Step-3.5 gate, in resolved order: /tmp/cx_dedup_keys.txt (the ordinal set, whitespace-separated) and /tmp/cx_keymap.tsv (one dedup_key<TAB>cite_key line per entry — the ordinal→cite-key pin). Step 3.5 builds a coverage manifest (ordinal → cite key → title hash) from /tmp/cx_keymap.tsv + the .bib and verifies A against it as a mapping, so a citation dropped or substituted downstream fails the run — a bare count or ordinal-set check would pass a substitution that keeps the count.

Step 2 — Run A and B blind to each other

This is a read-only extraction fan-out in the sense of ../shared-references/fan-out-pattern.md: A and B are two shards that only extract records (each returns an entries[] set keyed by dedup_key — never by list position, never a B-visible cite key, never a quality ranking). Each shard returns the {shard_id, entries:[{dedup_key, …}]} envelope of ../shared-references/fan-out-pattern.md, and the executor runs the mechanical dedup_key join below before C. No shard assigns a MATCH/MINOR/MISMATCH/NEEDS_WEBCHECK label at all — the main agent assigns all four in Step 4 from C's field evidence, and only its own web-confirm edits the .bib.

Dispatch (tier-portable). On this host there is no Claude Agent tool, so the mainline's Tier 1 (Workflow-concurrent) and Tier 2 (Agent) forms both degrade here: run A, then B, then C one after the other, each in the freshest context the host can give. The join and the field-diff are identical to the mainline. Blindness is not automatic here (see the mirror adaptation note above): B sets blind:true only if its context provably did not inherit the .bib, and blind:false otherwise — in which case Step 3.5 downgrades every accept to ESCALATE and the run flags rather than certifies. B is prompted with only the title+first-author list and is forbidden from reading any local file; but when B is not run in an isolated context, that prohibition is not enforced (B could observe the parent's .bib read, or A's output), which is exactly why an un-isolated B must attest blind:false and the gate then certifies nothing. Isolation is the guarantee; the prompt restriction alone is not.

Breadth. The shard set is fixed at three by the design, not by a budget: two records are the minimum for a double-blind diff (one per provenance), and the third is the differ that must have produced neither. Breadth is not a swept parameter here, so there is no breadth/cost trade-off to bound — but note the ceiling: two independent records, not an ensemble.

Acceptance gate (provenance, per ../shared-references/acceptance-gate.md). This skill is not a loop and has no self-terminating accept gate; it runs once over a fixed citation set. Type-A (executor may self-judge): the dedup_key join balanced, every entry labelled, the .xlsx written. Type-B (merit — is the entry bibliographically correct): never delegated to a shard. A MISMATCH or a NEEDS_WEBCHECK resolution requires the main agent's own primary-source fetch — no fetch, no finding. A MATCH/MINOR rests on the two independent records agreeing, without a third fetch; that is weaker evidence than a fetch, so read a no-flag MATCH as "two sources concur", not "verified against the publisher of record".

Requirement (4) is discharged by the deterministic branch, not by a jury. fan-out-pattern.md admits "a single cross-model jury step — OR a deterministic verifier gate"; this skill takes the second: scripts/cx_verify.py (Step 3.5) is an external process that decides MATCH/MINOR by declared normalization and fails closed to ESCALATE otherwise — the same script and the same verdicts on this host as on the mainline.

The limit, stated plainly: the accept path is mechanical and a MISMATCH needs the main agent's own primary-source fetch, but the executor still reads that page, so this skill does not deliver cross-model acquittal and does not replace one — which is why it is meant to run in addition to citation-audit (a single cross-model reviewer), not instead of it. Never report a MISMATCH, least of all a fabrication finding, on shard text alone.

• Agent A (repo-only): read the .bib; extract each cited entry verbatim (brace-matched, no reformatting) → /tmp/cx_A_ourbib.json {"shard_id":"A","entries":[{"dedup_key","key","bibtex"}]}. Explicit instruction: do not search the web.
• Agent B (web-only): given ONLY the title+first-author list from Step 1, re-fetch each paper's record from the web and emit a clean BibTeX per paper → /tmp/cx_B_web.json {"shard_id":"B","blind","entries":[{"dedup_key","title_queried","found","source_url","bibtex","sources_tried","note"}]}. Explicit instruction: do not read any local file / .bib; set found:false + a note if a paper cannot be confirmed; never fabricate a field.
  • blind attestation (set once, for the whole B shard). B sets blind:true only if it ran in a context that could not have seen the .bib — a genuinely isolated dispatch that did not inherit the main agent's history. If B cannot guarantee that (e.g. it ran in the main context), it MUST set blind:false. The Step-3.5 gate refuses to certify a MATCH/MINOR on any entry that is not blind-attested, so a false blind:true is the one thing that would defeat the whole cross-check — never assert it to "pass".
  • Do not restrict the search to arXiv/DBLP. Many legitimate references are workshop tech reports, company research blogs, or proceedings pages that never appear on arXiv. If a title is not on arXiv, B MUST also run a general web search and open the landing page its own search returns (a project / blog / proceedings URL) before concluding found:false. B works from the title+first-author query only — it must NOT be handed, and cannot use, the .bib entry's url field (that stays with the main agent's Step-4 webcheck). A citation being absent from arXiv is NOT evidence it is fake.
  • Record sources_tried per entry (e.g. ["arxiv","crossref","semantic-scholar(429)","web"]) so a found:false from a degraded search (a source was down or rate-limited) is distinguishable from a genuine not-found. Note any source that failed/blocked in the entry's note.

On return, the main agent joins A and B on dedup_key — every ordinal from Step 1 must appear exactly once on each side. A missing or duplicated dedup_key, or an unbalanced count, is a fail-closed stop (re-run the offending shard), never a silent drop or a positional guess. This mechanical join replaces order-coupling and is judgment-free — it decides nothing about any citation, only that the two extractions line up before C diffs them.

Step 3 — Run C, the field-diff extractor (after A+B return)

C extracts, it does not adjudicate. Computing a field-by-field delta is mechanical extraction; deciding that an entry is MATCH (i.e. admitting it as correct) is the acceptance verdict, which ../shared-references/fan-out-pattern.md reserves for the executor. So C emits per-field evidence, not a per-entry verdict: for each field it reports same / differs (with both values verbatim) / absent, plus the routing flags below. The main agent assigns every final MATCH|MINOR|MISMATCH|NEEDS_WEBCHECK in Step 4 from that evidence. A shard that returns a verdict label is out of contract — the same rule proof-checker and research-lit state for their shards.

A third pass (a fresh-context run — this host grants no delegation tool) reads both JSONs — it produced neither — and, on each dedup_key-joined pair, diffs the two records field by field: title (ignore case/braces), author set AND order, year, venue (NeurIPS ≡ "Advances in NIPS"; note a genuinely different event), volume/pages, arXiv id / DOI. Output /tmp/cx_C_fielddiff.json: {"shard_id":"C","entries":[{"dedup_key","key","blind","found","sources_tried","url","fields":{"<field>":{"status":"same|differs|absent","ours","web"}},"flags":[...]}]} (found/sources_tried/blind copied verbatim from B, url from A, so Step 4 and the gate can act without re-reading the shard files) (keyed by the joined dedup_key) plus a summary {entries, fields_by_status:{same,differs,absent}, flags_by_type} — counts of mechanical field states, not a verdict tally.

Critical routing flag for C (this prevents the most damaging false positive): if B reports found:false for an entry whose A-side .bib type is @misc (or otherwise carries a url/howpublished instead of an arXiv id / DOI), and B's sources_tried shows it only queried indexers that cannot see that URL (arXiv/DBLP/etc.), C MUST attach the flag url_only_source_unqueried — and MUST NOT report the entry as absent-from-web. B's index-based method structurally cannot confirm a blog/tech-report citation; only the main agent's direct url fetch in Step 4 can. C likewise attaches degraded_search when sources_tried shows a source was down or rate-limited, and web_record_absent whenever B returned found:false for any reason. These flags force the entry into the main agent's Step-4 queue; none of them is a finding about the citation — they record what B's search did, not whether the reference is sound.

Step 3.5 — Run the deterministic verifier gate (cx_verify.py, mandatory)

This is the fan-out's requirement-(4) gate: fan-out-pattern.md demands "a single cross-model jury step — OR a deterministic verifier gate — that is identical across all three tiers." This skill has no cross-model jury, so the gate is an external process. It is the same script and the same verdicts on this host as on the mainline — the dispatch of A/B/C degrades by tier, the gate does not. The gate recomputes both the field diff and the routing flags from A's and B's own raw records and reads B's blindness attestation from B directly; C's flags are advisory only (unioned with the recompute) and a C schema violation fails closed — so C is not in the trust path for the diff or the routing. Resolve $CX_VERIFY with the Codex hybrid chain (managed project install, in-repo checkout, ARIS repo fallback, then the copied global Codex skill install). This is Policy A — skill-local gate:

Resolver note (owner-local, per ../shared-references/integration-contract.md). cx_verify.py is a single-skill helper under this skill's own scripts/, resolved via the Codex hybrid chain below. It deliberately ships no tools/cx_verify.py shim — it has no legacy tools/ entry to forward from (unlike the Phase-3 moves that kept one) — which is the owner-local Layer-0 exception the contract's Policy-A row registers.

CX_VERIFY=""
cd "$(git rev-parse --show-toplevel 2>/dev/null || pwd)" || exit 1
if [ -z "${ARIS_REPO:-}" ] && [ -f .aris/installed-skills-codex.txt ]; then
    ARIS_REPO=$(awk -F'\t' '$1=="repo_root"{print $2; exit}' .aris/installed-skills-codex.txt 2>/dev/null) || true
fi
# Global pointer written by smart_update_codex.sh, for hosts with no per-project install.
if [ -z "${ARIS_REPO:-}" ] && [ -f "$HOME/.aris/repo" ]; then
    ARIS_REPO=$(cat "$HOME/.aris/repo" 2>/dev/null) || true
fi
[ -f ".agents/skills/citation-crosscheck/scripts/cx_verify.py" ] && CX_VERIFY=".agents/skills/citation-crosscheck/scripts/cx_verify.py"
[ -z "$CX_VERIFY" ] && [ -f "skills/citation-crosscheck/scripts/cx_verify.py" ] && CX_VERIFY="skills/citation-crosscheck/scripts/cx_verify.py"
[ -z "$CX_VERIFY" ] && [ -n "${ARIS_REPO:-}" ] && [ -f "$ARIS_REPO/skills/citation-crosscheck/scripts/cx_verify.py" ] && CX_VERIFY="$ARIS_REPO/skills/citation-crosscheck/scripts/cx_verify.py"
[ -z "$CX_VERIFY" ] && [ -f ~/.codex/skills/citation-crosscheck/scripts/cx_verify.py ] && CX_VERIFY="$HOME/.codex/skills/citation-crosscheck/scripts/cx_verify.py"
[ -z "$CX_VERIFY" ] && {
  echo "ERROR: cx_verify.py not resolved at .agents/skills/citation-crosscheck/scripts/, skills/citation-crosscheck/scripts/, \$ARIS_REPO/skills/citation-crosscheck/scripts/, or ~/.codex/skills/citation-crosscheck/scripts/." >&2
  echo "       The requirement-(4) gate cannot run; do NOT hand-assign MATCH/MINOR in its place. Fix: rerun install_aris_codex.sh, export ARIS_REPO, or copy the citation-crosscheck skill into ~/.codex/skills/." >&2
  exit 1
}
python3 "$CX_VERIFY" --selftest || exit 1          # built-in cases; fail = do not trust the gate
# Build the coverage manifest (ordinal → cite key → title hash) from Step 1's ordinal PIN
# (/tmp/cx_keymap.tsv) + the .bib, using the gate's OWN parser. This is independent of A, so
# the gate can verify A against it as a MAPPING. ($BIB = the resolved .bib path from Step 1.)
python3 "$CX_VERIFY" --build-manifest --bib "$BIB" --keymap /tmp/cx_keymap.tsv \
        --out-manifest /tmp/cx_manifest.tsv || exit 1
# The gate RECOMPUTES the field diff AND the routing flags from A's and B's own raw records
# (`web_record_absent` from B's `found`, `degraded_search` / `url_only_source_unqueried` from
# B's `sources_tried` + A's fields), and reads B's blindness attestation from B directly. C's
# flags are ADVISORY only, unioned with the recompute, and a C schema violation fails closed —
# so a faulty/omitting/adversarial C can neither hide a discrepancy, forge a MATCH, nor wave an
# entry through by omitting a flag. Coverage is MANDATORY: `--expect-manifest` verifies the
# ordinal→key/title MAPPING against A (catching a drop-and-substitute the ordinal-set check
# cannot); `--expect` / `--expect-keys` add the count and ordinal-set checks. An empty artifact,
# a duplicate/absent/substituted key, a dropped citation, or A/B/C key-sets that disagree all
# exit non-zero rather than reading as "clean".
python3 "$CX_VERIFY" --a /tmp/cx_A_ourbib.json --b /tmp/cx_B_web.json --c /tmp/cx_C_fielddiff.json \
        --expect "$CITED_KEY_COUNT" --expect-keys /tmp/cx_dedup_keys.txt \
        --expect-manifest /tmp/cx_manifest.tsv \
        --json /tmp/cx_gate.json || exit 1

What the gate decides, and what it refuses to decide:

• MATCH — every compared field equal after declared normalization (LaTeX accent/brace folding, case, punctuation; an order-preserving surname list; a fixed venue-alias table).
• MINOR — the sole difference is preprint-vs-published venue for the same work.
• ESCALATE — everything else, fail-closed: any identifying field differing (authors, year, title, doi, arxiv), a secondary field differing, an identifying field absent on one side, a venue pair not in the declared table, any routing flag, found != true, or an entry that is not blind-attested (blind != true). A MATCH/MINOR that lacks the blindness attestation is downgraded to ESCALATE: the run can still flag a discrepancy, but it may not certify a match. This is what enforces the double-blind claim mechanically — a host that cannot dispatch B in isolation (so B might have seen the .bib) sets blind:false and the gate refuses to certify anything, turning the check into a labelled heuristic rather than a false certification.

The gate never emits MISMATCH. A discrepancy becomes a finding only when the main agent reproduces it against the publisher of record, so the accept path is mechanical and the reject path is externally evidenced. Author order is preserved by the normalizer on purpose — a re-ordered author list is one of the defects this skill exists to catch, so it must not normalize to equal.

Step 4 — ASSIGN every verdict (main agent, mandatory)

No verdict arrives pre-assigned from a shard. Read /tmp/cx_gate.json (the gate's recomputed verdicts and per-field evidence) — C's cx_C_fielddiff.json is audit-only and must not override the gate. The invariant of this step: every MATCH/MINOR/MISMATCH rests on either (a) the gate's mechanical decision or (b) a completed main-agent primary-source fetch. No shard signal — a differs, an absent, B's found:false, or a routing flag — is itself a finding. Two exhaustive cases:

• Gate said MATCH or MINOR → adopt it (case (a), mechanical). Do not re-litigate a mechanical equality decision from prose, and do not silently upgrade it to MISMATCH; if you believe the gate is wrong, the fix is the gate's normalization table plus a --selftest case, not a hand-edit of one row. (What a no-flag MATCH means: two independently-produced records concur — not "verified against the publisher of record".)

• Gate said ESCALATE → the main agent MUST complete a primary-source fetch before it may assign any of MATCH/MINOR/MISMATCH/NEEDS_WEBCHECK. This is a procedure, not a first-match menu: do every applicable fetch, then decide — so no earlier branch can preempt a stricter one.

  1. Fetch. Identify and WebFetch the primary source(s):
     • the entry's own url / howpublished whenever the .bib carries one — always for the url_only_source_unqueried / web_record_absent cases (this is the .bib's url, which B never saw); and
     • the canonical index the fields point at — the arXiv abstract for an arXiv id, the DOI resolver for a DOI, else the venue / proceedings page. For an unconfirmed-existence entry, also run the main agent's own general web search (independent of B). Record every URL and query tried.
  2. Decide from what the fetch(es) returned — each terminal rests on a completed fetch:
     • Primary source confirms the .bib (title + author set/order + year + id agree) → MATCH (annotate the source; for a url-confirmed non-arXiv entry note "blog/tech-report, web-confirmed"). A gate differs/absent the source does not reproduce is downgraded here, with the reason recorded.
     • Same work, only preprint-vs-published differs → MINOR.
     • Primary source contradicts an identifying field (author set/order, year, venue-as-different-event, arXiv id / DOI, or a substantive title/subtitle/word change; or a moved page/volume range) → MISMATCH, citing the fetched value. (Field-discrepancy MISMATCH — the source reproduced it; this guards against a B/C hallucination inventing a wrong "fix.")
     • Existence unconfirmable → MISMATCH (fabrication) only when BOTH hold: the entry's url is absent / dead / contradicting, and the main agent's own general search also failed. A dead url alone, or B's found:false alone, is never enough — this is the one path to a fabrication finding and it rests on the main agent's own null result, not on B's miss.
     • Fetch inconclusive (source unreachable / genuinely ambiguous) → NEEDS_WEBCHECK, left for a human. Never default an inconclusive fetch to MATCH or MISMATCH.

  A one-sided absent field is not resolved "from the fields both sides share": the gate already escalated it, and the verdict comes from the fetched primary source per the ladder above (an absence becomes MISMATCH only when the .bib asserts a field the source contradicts; otherwise MATCH/MINOR per the fetch, with the absence noted in Detail).

Every entry leaves Step 4 with exactly one of the four labels, each MATCH/MINOR/ MISMATCH backed by the gate or a completed main-agent fetch. If an ESCALATE's evidence fits none of the outcomes above, that is a fetch not yet done, not licence for a shard to decide. Do not edit the .bib on shard evidence alone: every applied fix traces to a main-agent fetch.

Step 5 — Emit the spreadsheet + apply confirmed fixes

Build the .xlsx (openpyxl) with one row per citation and columns: # | BibKey | Link | Our BibTeX | Web BibTeX | B source | Verdict | Author check | Year | Detail | Fix. Color the Verdict cell: green = MATCH, yellow = MINOR or a NEEDS_WEBCHECK the main agent resolved to MATCH (annotate how), orange = MISMATCH. Add a Summary sheet with the counts and the fixed/optional lists. Apply only the main-agent-confirmed MISMATCH fixes to the .bib; if the paper is compiled, rebuild so the .bbl picks them up and re-verify the page count is unchanged. Report MINOR items as optional (do not auto-apply preprint→published upgrades; that is an author choice).

Key rules

• Blindness is the mechanism. If B ever sees the .bib, the cross-check collapses into a single-source read and loses its power. Enforce it in the prompt.
• Never fabricate a field in A, B, or C. found:false + a note beats a guess.
• A non-arXiv miss is not a fabrication. @misc/blog/tech-report/proceedings-URL citations are legitimate and invisible to arXiv/DBLP search. B must try the general web from the title+first-author prompt only; C flags an unconfirmed URL-bearing entry (url_only_source_unqueried) and the main agent assigns NEEDS_WEBCHECK and fetches the entry's own url in Step 4. A MISMATCH (fabrication) requires both a dead or contradicting url and the main agent's own general web search also failing (per Step 4) — a dead url alone is never enough. This is the skill's most dangerous false-positive if skipped.
• Shards extract; the main agent adjudicates. A, B and C emit records and per-field deltas. Every MATCH/MINOR/MISMATCH/NEEDS_WEBCHECK is assigned by the main agent in Step 4, and every MISMATCH is web-confirmed by the main agent before the .bib is touched. The shards propose; the main agent's own fetch disposes.
• Bibliographic only. Context-fit ("is it cited for a claim the paper supports?") is out of scope — that is citation-audit's job. Recommend running both before submission.
• Report, do not silently upgrade. Preprint-vs-published and cosmetic key/year-label mismatches are MINOR; list them, leave the choice to the author.