Every primitive chip in the annotator, what it means, and what the CAM planner does with it. Grade with the machinist's intent — the chip answers "what operation makes this face", not "what shape is it". The specific face role and its umbrella (pocket_wall vs pocket) are both always correct; pick whichever is fastest.

◆pocket

whole enclosed cavity (feature-level tag)

rough (adaptive/trochoidal) → finish walls → finish floor

◆open_pocket

pocket that runs off one or more part edges

lateral entry from outside the stock — no ramp/plunge

◆pocket_floor

flat bottom of a cavity

floor finish pass, flat endmill

◆pocket_wall

vertical/steep cavity side

wall finish contour passes

◆pocket_fillet

RADIAL corner round (vertical axis) — curvature in XY only

plain endmill Ø ≤ 2R sweeps it during the wall contour — free

◆floor_fillet

AXIAL blend where wall meets floor — the radius adds Z depth (floor radius, boss-base sweep)

corner-radius/bullnose or ball-nose — its own pass, special cutter

◆hole

plain drilled bore (through or blind)

spot → drill

◆counterbore

two coaxial bores, flat shoulder — cap-screw seat

drill pilot → flat-bottom bore/endmill the seat

◆countersink

conical entry seat (82/90/100°)

drill → countersink tool

◆spotface

counterbore too shallow to be one — a cleaned seat

drill → shallow facing with endmill

◆reamed_hole

H7/H8 fit bore

drill undersize → ream

◆bored_hole

precision large bore

drill/helical → single-point boring bar

◆sae_port

SAE J1926 / ISO 6149 port form

drill → step-bore → chamfer → thread, to spec

◆tapped_hole

internal thread

tap-drill → tap (or thread mill M6+)

◆external_thread

thread on the outside of a boss

thread mill / die

◆slot

closed slot — end walls present

plunge/ramp in, side-mill the length

◆open_slot

runs off one or both stock edges

lateral entry from outside the stock

◆slot_floor / slot_wall

face-level tags of the above (aspect ≳ 3)

as slot

◆keyway

slot at a standard key width

side mill, tight width tolerance

◆groove / v_groove

narrow channel / 45–60° V section

slot cutter / chamfer-V single sweep

◆t_slot

undercut T section

endmill the leg → T-slot cutter sweep

◆dovetail

undercut angled walls

dovetail form cutter

◆o_ring_groove

annular gland, AS568 sizing

groove + finish pass, inspection callout

◆boss

raised island the surrounding material is cleared from

clear surroundings → boss wall finish

◆boss_wall

the island's own side wall

perimeter finish (conventional if slender)

◆land

open flat area at a level — impeller base, seal land, a plain flat island (scores with pocket floor)

endmill clearing / light facing at level

◆rib

thin standing wall or fin — impeller blade, stiffener. Machined as an island (scores with boss); grade what you see

clear both sides → light finishing passes (slender: climb only)

◆contour

the part's outer profile wall

2D contour around the part

◆step

any OPEN floor at depth — ledge, shoulder, platform (enclosed → pocket_floor; narrow → slot_floor)

face/contour at depth

◆parting_surface

mold split line

zero-mismatch finish — flag for review

◆face_mill

finished flat (top/bottom)

face mill with wiper inserts

◆surface

3D contoured / freeform / organic region — includes domes and sculpted skins

ball-nose scallop raster: stepover s = 2√(2rh−h²) for target scallop h; tool radius ≤ tightest concave radius of the region

◆ruled_surface

single-curvature skin

flank-mill candidate (5-axis) or scallop

◆ramped_profile

continuous Z change along a path

3D contour strategy

◆variable_radius_fillet

blend whose radius changes along the edge

swept ball-nose — no single corner-radius tool exists

◆chamfer

flat angled edge break (30–60°, shallow)

chamfer mill sweep — depth is the signature, not area

◆fillet

constant-radius external blend (tangent joints)

ball-nose or corner-radius pass; part of a surface region when it joins organic skin

◆engrave

shallow text/logo clusters

V-tool engraving, very low DOC

◆vent_channel

0.02–0.05mm mold vent

micro-tool / engraver

◆undercut

generic overhang the spindle can't see

lollipop / EDM / re-fixture — flag

◆stock

raw, untouched (clamped face etc.)

no op

◆other

engine gave up — the highest-signal thing you can label

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Related per-face properties the rules (and the refinery's proposals) can use: convexity (+1 bulges out of material, −1 dents in), curv_mean_abs (1/radius), curv_variance (≈0 = constant-radius blend), sphere_radius, torus_minor_radius (= blend radius).