Summary

• Consolidates the in-tree v0.31.0 CHANGELOG onto a single 2026-04-19-dated release entry, rolling up everything landed between PR release: aprender v0.31.0 #748 (0.30→0.31 bump) and PR docs(mcp): spec v1.2.0 — pmcp 2.3 adoption, drop pforge, add M5 plan #888 (MCP spec v1.2.0 + parity epic closure).
• No code change, no version bump — all 78 workspace crates already at 0.31.0 from PR release: aprender v0.31.0 #748. This PR is the CHANGELOG-finalize step that unblocks tagging v0.31.0.

What rolls into v0.31.0 (2026-04-19)

• MCP Server M1–M3 (feat(mcp): apr mcp M1 skeleton — MCP server over stdio #864, feat(mcp): M2 slice 1 — apr.validate subprocess wrapper #865, feat(mcp): M2 slices 2+3 — apr.tensors, apr.bench + shared run_apr helper #866, feat(mcp): M2 slices 4+5 — apr.qa, apr.trace #867, feat(mcp): M2 dispatcher hardening — FALSIFY-MCP-005 + -007 gates #868, test(mcp): FALSIFY-MCP-002 strict — JSON Schema Draft 7 meta-validation #869, feat(mcp): M2 slice 6 — apr.run synchronous inference wrapper #870, contract(mcp): add apr-mcp-tool-schemas-v1.yaml as codegen source of truth #871, feat(mcp): ship apr.serve fire-and-forget subprocess wrapper (M2) #872, docs(book): add MCP server chapter with .mcp.json client examples (M2) #874, feat(mcp): FALSIFY-MCP-008 build.rs schema codegen (apr.version migrated) #880, feat(mcp): M3 — apr.finetune synchronous wrapper (8th Phase-1 tool) #881, feat(mcp): M3 — FALSIFY-MCP-006 notifications/cancelled SIGTERM→SIGKILL #883, feat(mcp): M3 — migrate 7 remaining tools to codegen schemas (FALSIFY-MCP-008 full) #884, docs(book): MCP server chapter — M3-complete state #885, feat(mcp): M3 — notifications/progress for apr.finetune #887) — 9 apr tools over stdio JSON-RPC 2.0, YAML-codegen'd schemas (FALSIFY-MCP-008), notifications/cancelled + progress, Draft 7 meta-validation.
• apr code — Claude Code parity epic CLOSED at v5.1 (docs(mcp): spec v1.2.0 — pmcp 2.3 adoption, drop pforge, add M5 plan #888) — 21 rows, 14 SHIPPED / 3 PARTIAL / 4 NONE; PMAT-CODE-PARITY-MATRIX-001 both closure conditions met; 10 tickets closed in one cycle (P0×4, P1×5, P2×2).
• Contracts harness — pv check-parity SEMANTIC gate + new apr-claude-proxy-v1.yaml DRAFT (promotes to ENFORCED at M6-α).
• SHIP-TWO-001 teacher shipped — paiml/qwen2.5-coder-7b-apache-q4k-v1 (7.5 GB .apr, Apache-2.0) on HuggingFace; apr validate-manifest + --live + FALSIFY-PM-007 safetensors dtype Poka-Yoke.
• Perf — decode hot-path hygiene HP-001/002/003 (184→382 tok/s on 1.5B Q4_K_M, 2.07×); 32-tok bench 442.8→479.9; FlashDecoding gated for small models.
• Model/format — ALB-093: Streaming quantize for large models (57+ GB OOM) #434 streaming APR→Q4K for ≥4 GiB; Per-layer F32 dequantization for CPU inference (32B OOM on 119GB) #478 per-layer dequant; TensorDType::from_u8 missing GGML Q4_0/Q5_0/Q5_1 dtype mappings #375 GGUF Q4_0/Q5_0/Q8_0 fallback; Multiple bugs: empty input, panic on missing model, argument parsing #90 honest brick benchmarks; BPE tokenizer uses O(n²) greedy rescan instead of priority queue #378 priority-queue BPE (2.06× encode).
• CI — sccache pilot (ci: enable sccache pilot (heavy workload — APR-MONO) #894), nextest opt-in (feat(ci): opt in to cargo nextest run (Phase 2 pilot) #897), F-203/RP-002/tui_load flaky-test fixes (fix(ci): F-203 SIMD timing flake — main CI andon #875, fix(ci): tui_load flaky perf test — warmup + best-of-3 (ANDON) #878, fix(ci): RP-002 proptest fp32 tolerance — 0.1% below dim=8 noise floor (ANDON) #879).

Previous draft rolled in

The existing ## [0.31.0] - 2026-04-15 section was an rc cut. Its content (GH-375/GH-90/GH-378/apr serve plan hf:///apr eval --task classify/apr compile/--arch gemma|falcon|mamba|t5/apr finetune --task classify) is merged into the 2026-04-19 authoritative entry so release history stays single-authoritative.

Test plan

• cargo check --workspace — clean
• Single [0.31.0] section in CHANGELOG (no 2026-04-15 duplicate)
• Empty [Unreleased] section
• All required CI checks green (workspace-test, ci / gate, ci / lint, ci / test, ci / coverage, ci / security, ci / provenance)
• Tag v0.31.0 on merge commit after squash-merge

🤖 Generated with Claude Code