Milestone 3.5.D.2 — Wire Assemble into dispatchProviderCompletionCopy Anchor Link

Status: Completed Goal: Track D — Proxy Integration
Phase: 3.5 — Extraction & Context Assembly
Estimated effort: 2 days
Track: Track D — Proxy Integration
Depends on: Milestone 3.5.D.1 (Go gRPC context client)

---

Why This Milestone ExistsCopy Anchor Link

This is the exact seam where context assembly replaces/extends directive injection in the proxy hot path. h.contextClient == nil should be a legitimate, fully-supported runtime mode falling back to Phase 2 static-directive behavior — making Phase 3.5 additive, not a hard fork.

---

What shippedCopy Anchor Link

• IBEX_CONTEXT_ENABLED (default false) + nil ContextClient are independent gates to Phase 2 applyDirectiveInjection (no Assemble gRPC).
• dispatchProviderCompletion calls applyContextOrDirectiveInjection before Complete; Assemble Fallback still applies Phase 2 directive injection.
• X-IBEX-Skip-Memory skips Assemble entirely (directive injection still runs).
• Response headers X-IBEX-Memories-Injected, X-IBEX-Context-Tokens, X-IBEX-Context-Fallback on non-stream and SSE paths when Assemble was attempted; omitted on Phase 2 (disabled/nil/Skip-Memory) for bit-identical headers.
• Embedded ibex JSON / IBEX_CONTEXT_EMBED_METADATA remains 3.5.D.3.

---

Success signalsCopy Anchor Link

• dispatchProviderCompletion wired with context assembly
• IBEX_CONTEXT_ENABLED=false reproduces exact Phase 2 behavior (regression fixture)
• X-IBEX-Skip-Memory header skips the gRPC call entirely (not just discards result)
• Response headers X-IBEX-Memories-Injected, X-IBEX-Context-Tokens, X-IBEX-Context-Fallback set correctly (D.2 owns plain headers; D.3 owns embedded metadata)
• Repo guards / CI checks still pass

PrerequisitesCopy Anchor Link

• Milestone 3.5.D.1 (Go gRPC context client)