fix(mcp): search/find/neighbors family (#353, #354, #355, #356)

[HumanBean17]

What

Four correctness/contract fixes in the search/find/neighbors family (mcp_v2.py).

#353 — search filter was post-filtered after pagination

search(filter=…) applied the NodeFilter only as a post-filter on rows already sliced by offset/limit, instead of pushing the predicates into the LanceDB query. A filtered page could shrink to 0–2 results even when many matches existed deeper in the ranking; paginating a filtered search gave inconsistent pages. Fix: forward role/module/microservice/capability/exclude_roles from the NodeFilter into run_search (which already accepted them). _node_matches_filter still re-checks every row afterward (covers the non-pushdownable fields and is the contract guarantee).

#354 — unresolved-call-site NodeRef dropped the callee name

NodeRef had no name field, so other=NodeRef(..., name=callee) was silently dropped (pydantic default extra="ignore"), leaving every unresolved-call-site edge with fqn="" and no readable callee in the structured ref. Fix: add name: str | None = None to NodeRef.

#355 — has_more_results computed but dropped

find_v2 computed has_more_results for the hint payload but FindOutput had no such field, so MCP clients never learned whether more pages existed. Fix: add has_more_results to FindOutput (wired) and NeighborsOutput (computed where neighbors paginates in Python; None on the single-origin CALLS SQL-paginated path, where calls_row_count is the signal).

#356 — neighbors generic Cypher typed-union RETURN (latent portability)

The flat-label neighbors query RETURNed a fixed superset of attributes regardless of which edge types matched — the anti-pattern AGENTS.md warns about. Missing columns return None on LadybugDB (no live bug), but a stricter binder (Kùzu) would error. Fix: issue one single-label query per edge type, RETURNing only that type's columns (via _FLAT_EDGE_ATTR_COLUMNS, aligned with the REL TABLE schemas in build_ast_graph.py). label(e) = $label scalar equality per the Cypher note.

Tests

One new test per fix, plus one FakeGraph test-double update:

• test_search_pushes_nodefilter_into_run_search — asserts the 5 fields reach run_search.
• test_unresolved_call_site_noderef_carries_callee_name — _unresolved_site_to_edge keeps callee in other.name.
• test_find_exposes_has_more_results — has_more_results True mid-list, False past the end.
• test_neighbors_flat_labels_select_columns_per_edge_type — each per-label query RETURNs only that type's columns.
• test_neighbors_route_in_http_calls_returns_callers FakeGraph made label-aware (the per-label split now calls _rows once per label; the old double returned the same canned row for both labels).

.venv/bin/python -m pytest tests/test_mcp_v2.py -q
# 111 passed, 1 skipped

Notes

• No re-index, env-var, or ontology_version change. The NodeRef.name / *Output.has_more_results additions are additive on the MCP output schemas.
• The neighbors generic Cypher uses typed-union RETURN over heterogeneous edge types (latent portability risk) #356 change increases the number of _rows calls from 1 to N (one per flat label) for multi-label neighbors; N is small and these are indexed lookups.

Closes #353, closes #354, closes #355, closes #356.

🤖 Generated with Claude Code

[HumanBean17]

Addressed a finding from a multi-agent review pass:

has_more_results=None on the non-paginated CALLS path (low) — the single-origin CALLS branch set has_more_results=None unconditionally, but when paginate_in_sql is False (a node filter is set, include_unresolved, or dedup_calls) the full filtered set is loaded and returned, so the client already has everything — None ("unknown") undercut #355's goal of letting a client avoid a probe. Now False when not SQL-paginated, None only when it is. Added a regression test covering both modes (filtered → False, unfiltered single-origin → None); verified red→green. test_mcp_v2.py 112 passed.

[HumanBean17]

Addressed 2 review findings:

1. _FLAT_EDGE_ATTR_COLUMNS silent fallback — now asserts at import that it covers every EdgeType exactly. A future edge type missing here would otherwise SELECT only (id, label) and yield empty-attr edges; the assert trips on both a missing and a stale entry.
2. name: null in hints — the find/neighbors hint payloads used bare model_dump(), leaking name: null (and other null fields) into generate_hints. Switched to exclude_none=True: these dicts feed hint generation only (not the tool result), generate_hints reads fields defensively via .get, and it matches the adjacent filter dumps. Verified against test_mcp_v2 / test_mcp_hints / test_client_hint_recovery.