R17: Isolate optional reranking behind provider interface

[100yenadmin]

Keep Voyage reranking fork-only initially behind an optional provider interface. With no provider configured, preserve upstream ranking byte-for-byte. Tests use a deterministic local provider and require no network credentials.

Acceptance: provider failure has an explicit fallback/error policy, no-provider behavior is unchanged, and premium defaults stay outside generic upstream code.

Validation: deterministic ranking, no-provider, timeout, malformed response, and secret-redaction tests.

Parent epic: #39

Tracking ID: R17

[100yenadmin]

R17 implementation is staged in #79 at exact head 25a92c4a4a9fa88bff0a37e3529790efa77fe649.

Evidence gate completed locally:

• 273 focused rerank/schema/LocalBackend tests
• 56 wider LocalBackend regression tests
• 2 group-routing tests
• typecheck and build passed
• targeted lint: 0 errors
• no live index, runtime, package, release, or publication mutation

The feature is off by default, requires a repository allowlist, preserves rerank: false as a resolver-level bypass, validates provider output deterministically, and redacts URL/API credentials. Remote exact-head CI is now the remaining issue gate.

Evidence: /Volumes/LEXAR/Codex/session-notes/2026-07-13/gitnexus-fork-upstream-reconciliation/r17-optional-reranking.md

[evaos-code-review-bot]

evaOS issue enrichment

Issue: #56 - R17: Isolate optional reranking behind provider interface
State: open; milestone: GitNexus v1.6.10 Reconciliation - Sprint 3 - Retrieval Resilience and Scale Proof

Related issues/PRs: #39.
Existing labels: reconciliation, P1, evidence-gate, fork-only.
Suggested labels: bug, security, tests.
Suggested owners: none.

Related context

• EPIC: Reconcile evaOS GitNexus with upstream v1.6.10 #39 - mentioned in issue metadata; inspect for dependency, duplicate, or prior-decision risk.

Agent-start packet

Problem shape: R17: Isolate optional reranking behind provider interface - Keep Voyage reranking fork-only initially behind an optional provider interface. With no provider configured, preserve upstream ranking byte-for-byte. Tests use a deterministic local provider and require no network
Product fit: Architecture/integration issue; check repo policy, prior decisions, and operational constraints before implementation.
Implementation wedge: Start with a bounded adapter/contract or dry-run packet before changing live runtime behavior.

Build / borrow / buy scan:

• Build: identify the smallest implementation wedge that proves the issue without broad rollout.
• Borrow: inspect same-repo prior art, repo memory, GitNexus context, and allowlisted cross-repo examples first.
• Buy/use: deferred; no product, architecture, UX, library-choice, integration, roadmap, or market-positioning trigger detected.

Candidate sources:

• VISION.md / repo policy / repo-memory.md / GitNexus packet.
• Same-repo issues and PRs referenced by issue metadata.

Acceptance criteria:

• Preserve and execute the issue's stated acceptance criteria.
• Include source citations for any external OSS/library/current-market claims.
• Keep issue-enrichment comments sticky and idempotent.
• Keep labels, owners, reviewers, and roadmap fields suggestion-only.

Proof plan:

• Focused unit/fixture test for the changed planner behavior.
• Dry-run issue-enrichment evidence packet before live comment posting.
• Redaction check for issue body, citations, and generated markdown.
• Contract or degraded-mode proof before runtime promotion.

Known traps:

• Do not treat related links as proof by themselves; each source needs a reason why it matters.
• Do not scan old issue backlogs or exceed repo-level enrichment throttles.

Non-goals:

• Do not auto-apply labels, owners, reviewers, roadmap fields, or milestones.
• Do not bulk-enrich old backlog issues from this planner output.
• Do not claim external market or OSS research was performed unless cited sources are present.

Context-source taxonomy:

• [enabled] vision_repo_policy_memory_gitnexus: Use repo vision, policy, memory, and GitNexus first before external research.
• [enabled] same_repo_issues_prs: Issue metadata contains same-repo references.
• [deferred] allowlisted_cross_repo_github: Deferred until product, UX, market-positioning, or library-choice signal appears.
• [deferred] external_oss_examples: Deferred for low-research-value issue class.
• [deferred] library_api_docs: Deferred unless a library/API decision is present.
• [deferred] current_market_examples: Deferred for implementation-only issues.
• [enabled] internal_mcp_docs: Use internal docs/MCP context when available; missing context is degraded, not blocking.

Validation suggestions

• Confirm owner, acceptance criteria, and validation evidence before implementation.

Triage gaps

• Owner or reviewer signal not detected in issue body.

No labels, owners, reviewers, or roadmap fields were changed by this bot.

[100yenadmin]

R17 acceptance complete at PR #79 head 0a4efe86: optional Voyage reranking is isolated behind a provider interface, no-provider behavior preserves upstream ranking exactly, and deterministic tests require no network credentials. Focused 237-test proof and all 33 exact-head remote checks are green, including the transient Docker/Cosign rerun. PR #79 remains open for R24 integration.