Eliminate the external kicad-sch-api dependency by migrating all MCP
tools to the internal SchDocument class built on sexp_tree.py. This
fixes three serialization bugs (dropped global labels, TypeError on
local labels, mis-quoted property private keywords) and removes ~1,900
lines of workaround code.
New modules:
- sexp_tree.py: S-expression parser and round-trip serializer
- sch_document.py: schematic read/write/mutate API
- lib_resolver.py: symbol library search and resolution
- sch_helpers.py: shared load/validate/expand helpers
Migrated all 9 tool files, resources, and tests. Removed 5 workaround
functions from sexp_parser.py. 531 tests pass, ruff + mypy clean.
A4 is too small for real schematics. A3 matches US engineering
convention (close to ANSI B/Tabloid) and is KiCad's standard
template size. Batch JSON also supports paper_size field.
add_hierarchical_sheet now returns sheet_uuid and parent_uuid.
apply_batch accepts these as optional params to call
set_hierarchy_context() before placing components, fixing
kicad-cli netlist export for hierarchical designs.
Label collision detection: resolve_label_collision() shifts different-net
labels that share the same (x,y) coordinate by 1.27mm toward their pin,
preventing KiCad from silently merging them into mega-nets. Integrated
at both label placement points in apply_batch.
Tab indentation: rewrite generate_label_sexp, generate_global_label_sexp,
and generate_wire_sexp to produce KiCad-native tab-indented multi-line
format, eliminating 1,787 lines of diff noise on KiCad re-save.
Intersheetrefs property now uses (at 0 0 0) placeholder.
Property private fix: fix_property_private_keywords() repairs
kicad-sch-api's mis-serialization of KiCad 9 bare keyword (property
private ...) as quoted (property "private" ...), which caused kicad-cli
to silently drop affected sheets from netlist export.
243 tests pass, ruff + mypy clean.
Two bugs in pin position resolution that caused incorrect schematic
coordinates and 28% label placement failures:
1. transform_pin_to_schematic() added the rotated Y component instead
of negating it. lib_symbol pins use Y-up; schematics use Y-down.
Fix: comp_y + ry -> comp_y - ry.
2. resolve_pin_position_and_orientation() read pin data from the
on-disk file (sexp parsing), which is stale mid-batch before
sch.save(). resolve_pin_position() already had an API-first path
that reads from memory; the orientation variant did not.
Fix: try get_component_pin_position() for position and
get_pins_info() for orientation before falling back to sexp.
Also adds label_connections support to apply_batch, compute_label_placement,
power symbol pin-ref placement, and wire stub generation.
add_label bypasses kicad-sch-api serializer entirely — generates
s-expression strings and inserts them directly into the .kicad_sch
file via atomic write. Fixes two upstream bugs: global labels silently
dropped on save (serializer never iterates "global_label" key), and
local labels raising TypeError (parameter signature mismatch in
LabelCollection.add()).
add_power_symbol now falls back to sexp pin parsing when the API
returns None for custom library symbols (e.g. SMF5.0CA). Extracts
shared resolve_pin_position() utility used by both add_power_symbol
and batch operations.
Batch labels also fixed — collected as sexp strings during the batch
loop and inserted after sch.save() so the serializer can't overwrite
them.
kicad-sch-api has two parsing gaps: get_symbol_definition() returns
None for non-standard library prefixes (e.g. Espressif:ESP32-P4),
and there is no sch.global_labels attribute for (global_label ...)
nodes. This adds a focused parser that reads directly from the raw
.kicad_sch file as a fallback, integrated into the connectivity
engine, pin extraction, and label counting tools.
Root cause: kicad-sch-api doesn't back-populate comp.pins or sch.nets
on loaded schematics. All data is accessible through alternative APIs.
Pin extraction: use comp.get_symbol_definition().pins for metadata and
sch.list_component_pins(ref) for schematic-transformed positions.
Connectivity: new wire-walking engine using union-find on coordinates.
Walks wires, pin positions, labels, and power symbols to reconstruct
the net graph. Replaces broken ConnectivityAnalyzer/sch.nets fallbacks.
Eliminates 'unhashable type: Net' crash.
Hierarchy: use sch.sheets.get_sheet_hierarchy() instead of the broken
sheets.data.get("sheet", []) raw dict approach.
Labels: supplement sch.get_statistics() with sch.labels.get_statistics()
and sch.hierarchical_labels for accurate counts.
99 tests passing, lint clean.
