Tool count 131 -> 154; 474 -> 1242 collected tests.
The release exists for two measured reasons. A 149-tool catalog costs a client
~40,300 tokens before it has asked for anything, and a drafter searching the way
drafters think -- FILLET, BPOLY, QSELECT, WBLOCK -- scored df=0 against the stock
index, because those words were simply not in the data.
Discovery and batching
- DISCOVERY_MODE=search replaces the catalog with search_tools + call_tool,
ranked over an AutoCAD command and synonym corpus (discovery/aliases.py) on
top of fastmcp's BM25 index. Measured: 40,305 -> 356 tokens advertised.
- cad_batch runs a step list in one round trip; fields= projects result-heavy
responses. The `core` profile is gone -- discovery replaced it.
Honesty debt (Tier 0)
- OCS/ECS: `extrusion` appeared nowhere in this codebase, so mirrored and
rotated geometry reported coordinates that were quietly wrong. backends/ocs.py
translates at the backend boundary; every tool coordinate is WCS on both
engines, and a tilted plane refuses rather than answering with a number that
looks fine.
- drawing_save_as(fmt="dwg") wrote DXF bytes to a .dwg path. drawing_audit never
repaired. analysis_measure_area shoelaced points the caller typed in.
- ezdxf calls gained a per-call timeout, so one hung call can no longer wedge a
server whose document lock is a single asyncio.Lock.
Architecture
- The 1854-line backend ABC is 19 contract modules; @capability(key, reason=)
makes optional methods declarative and a gate fails on undeclared holes.
- 8 layout/viewport tools, CHSPACE, CAD_PROGID escape hatch.
- Wave A: selection filters, boundary tracing, hatch depth, annotation objects,
measurement -- 13 tools of a planned 39. The REGION and 2D-boolean family was
cut on evidence: add_region() yields zero ACIS bytes and the greiner_hormann
substitute loses 28.2% of the area on a square with one semicircular edge.
Verified against a live AutoCAD 2026, which found four COM defects no amount of
reading would have caught -- AcadPViewport has no ViewCenter, and the line that
set it had been swallowed by a bare except since v1.4.
Benchmark v3 (15 tasks) and what it caught
- v2 scored this server 10/10, which carried no information: every task in it
exercised something the server was built around. Five tasks were added because
they can fail, and three did while being written -- a hatch could not be
measured though the refusal listed HATCH as measurable, the boundary tools and
the measure tool disagreed about the same shape (139.2177 vs 139.2699), and a
circle stored as two bulged vertices measured 0.0.
- Competitor reports are NOT re-scored. They are pinned v1.4 runs against v2 and
were never asked these five questions; the chart shows those rows `not run`.
- Correctness A/B: 21/24 -> 24/24, zero regressions.
Performance, stated plainly
The published v1.4 perf report was recorded on CPython 3.14 and the new one on
3.11.15, so the apparent 2-6x speedup is the interpreter, not this release.
Re-measured on one interpreter, v1.5.0 is 28% slower creating entities and 22%
slower on the 10k roundtrip. Fully attributed: EZDXF_CALL_TIMEOUT=0 restores
v1.4.0's exact numbers. That is the deadlock fix being paid for, the knob is
documented, and winning it back is on the 1.6 roadmap.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Adds production-grade engineering features and tools: 2D GD&T (feature control frames + datum features) via engineering/gdt.py, ISO‑129 dimension tolerance support (engineering/tolerances.py) and an ezdxf/COM plumbing for toleranced dims, a scalar drawing score + invalidity ratio (engineering/scoring.py) wired into drawing_finalize, in-place entity editors (entity_edit_text/entity_edit_geometry), and a friendly drawing_settings facade. Includes server tool wiring, COM/ezdxf backend implementations, datum-consistency critique, many unit tests, README/CLAUDE/CHANGELOG updates, and a version bump to 1.2.0. Also corrects COM backend capability label (entities_2d).
Introduce the autocad-mcp-premium skill with workflow docs, examples, and references (.claude/skills/autocad-mcp-premium/*). Add PlanSpec/critique plumbing and engineering helpers (engineering/plan_spec.py, engineering/critique.py) plus tests and a smoke script. Extend backend API (backends/base.py) with corner operations and premium meta-tools (trim/extend/fillet/chamfer, drawing_plan, drawing_critique, point_from_snap, construction_xline/clear, drawing_apply_iso_layers, dimension_auto, entity_select_smart) and implement COM backend corner ops (backends/com_backend.py) with placeholders for meta-tools. Update CLAUDE.md to document the premium drawing rules and standard workflow. Misc: add examples, references, and tests for premium features, and minor server/backend adjustments.
Introduces an engineering/ package that lets MCP clients produce production-
quality technical drawings without LLM-improvised geometry. Adds 7 new MCP
tools, an 8-step pre-completion validator, and an automatic linetype + layer
bootstrap on drawing_new so CENTER/HIDDEN/PHANTOM and standard mechanical
layers (GEOMETRY, DIM, HATCH, TEXT, TITLEBLOCK, ...) are always available.
- engineering/gear.py: pure-Python involute math, 40+ points/flank, helical
+ spur front views, deterministic section A-A (no helix lines in section).
- engineering/keyway.py: DIN 6885 keyway table + parametric keyed bore /
side-section drawers.
- engineering/titleblock.py: ISO 7200 A3 (420x297 mm) title block; title
text is written verbatim to the title cell.
- engineering/validator.py: DrawingValidator with 8 checks (real DIMENSION
entities, no hidden orphans, linetypes loaded, bore + keyway in both
views when expected, title consistency e.g. forbid 'HELICAL SPUR GEAR'
when helix_angle truthy, saved-to-disk + file-on-disk, screenshot
exported, dwg path returned).
- backends/ezdxf_backend.py: AutoCAD-only linetype fallback (HIDDEN,
BORDER families) so ezdxf doc gets correct patterns when linetype_load
is called for names ezdxf.tools.standards does not ship.
- backends/base.py: concrete helpers set_layer_active / ensure_linetypes.
- server.py: Section 12 with 7 engineering tools, drawing_new(bootstrap=
True), and an ENGINEERING WORKFLOW block in the MCP instructions string.
- 30 new tests covering gear math, DIN6885 lookup, ISO A3 layout, title
verbatim, and every validator check. Tool count 89 -> 96.
