v0.6.0 — quality gates from the Cape Aurelia retrospective

Quality gates from the Cape Aurelia retrospective. The builder pipeline now catches the failure modes that turned a single-pass terrain build into three iterations: stacked-rectangle "ziggurat" terrain, rectangular underwater foundations, doors facing cliffs, sunken houses, single-colour walls, stale plans against rebuilt terrain, and self-cycling redstone that ships static. Skill-level changes only — no new MCP tools; still pairs with minecraft-bedrock-mcp-server and minecraft-bedrock-mcp-behavior-pack v0.3.0.

Added

• quality_contract schema in plan.toon — a machine-checkable list of the properties the finished build must satisfy: walkability between named rooms, door clearance and facing, headroom over stairs, block-mix ratios for wall surfaces, silhouette variance for naturalistic terrain, edge irregularity for coastlines and ridges, foundation naturalisation for underwater masses, water-column continuity for coasts, and site connectivity for transit networks.
• inspector parses the contract and runs the sampling algorithms — new reference/contract-checks.md documents each row's algorithm, threshold, and root-cause-routing behaviour on failure. Inspection now samples below sea level too.
• terraforming/reference/non-negotiable-enforcement.md — the non-negotiable rules (7-block, asymmetry, no monoculture, double-layer) expressed as machine-checkable contract rows.
• engineer/reference/setblock-redstone-limits.md — documents which redstone patterns self-start when placed via setblock and which need a one-time player right-click to kick. The inspection-recipe.toon schema gains a manual_kick block surfaced in every final report.
• minecraft-builder agent gains an honesty contract — before classifying a request it must flag blind-build limits up-front: no visual judgement from sampling, auto-cycling redstone needs a manual kick, naturalistic terrain needs a prototype-first checkpoint, and never silently downgrade scope.

Changed

• terraforming/SKILL.md adds two hard rules above the non-negotiables: heightmap-or-live-sculpt for any landform over ~30 blocks of extent (stacked rectangular fills produce the ziggurat artifact, every time), and foundations-are-terrain including underwater faces. Plus a mandatory prototype-first checkpoint before any large terrain.
• terraforming/reference/landforms.md documents the heightmap method (multi-octave value noise + radial falloff + organic-blob coves + blended build pads, baked to RLE structure tiles) and the talus-skirt rescue for naturalising an existing rectangular mass.
• terraforming/reference/command-budget.md adds bridge-pacing rules (≤6–8 heavy ops then a verify read), the 1500-RLE-runs-per-tile cap, ticking-area chunk-load guidance, and the canonical colon-namespace mcb:<project>_<element> rule.
• worker/SKILL.md adds stale-plan detection — sample the planned b (before-state) and HALT if the world doesn't match, rather than overwriting onto stale coordinates.
• blueprinter, planner, surveyor, and all planner-class skills now use mcb:<project>_<element> (colon namespace) as the canonical structure name.
• engineer/SKILL.md puts the setblock-redstone limit at the top: prefer lever/button/plate-triggered designs; declare a manual_kick step for any clock that needs one.
• Every planner-class skill (player-house, village-planner, city-planner, building-architect, landscape-architect, monument-builder, transit-architect, natural-landmarks) now emits a quality_contract block tailored to its domain.
• philosopher aggregates every manual_kick and surfaces them as an Outstanding manual steps section in the final retrospective.
• minecraft-builder agent's build loop now routes corrections by failure type rather than always to the worker — half-measures cost more iterations than fixing root causes.