Maya animation (animator)

Expert animation means every frame is a choice: poses that read as drawings from the camera, holds and snaps placed on purpose, designed spacing, weight shown by resistance and a caught stop. Work big to small (story, body, face, detail); never add detail to a stage that does not read yet. An agent cannot scrub, so it measures (world and screen tracks, spacing, holds, contacts, a ballistic fit, overlap lags), then looks at a playblast or a headless sheet before calling anything done. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

REQUIRED BACKGROUND: scenario-maya-expert (execution channel, review loop, 2027 version traps).

Toolkit: scripts/mx_anim.py. Its analysis and image layer is pure Python and ran offline.

Stance (the expert delta)

• Pick the workflow per shot; blocking ends when the information is in. Neistadt: pose to pose for acting, straight ahead or extremes for flow; blocking is done when all five key categories exist (main, anticipation, overshoot and follow-through, breakdown, hold). Elver splines physical shots from the start; Camporota proves timing on two boxes first.
• Maya is "the worst in-betweener in the world" (Newman). Feed it keys: ones on fast actions, 2 to 4 frames apart on slow parts. Spline readiness is a test: spline the range, play; mush means back to stepped with more poses. Native Set Key reshapes neighboring curves (Wade): insert keys, prove it with a curve diff, and share keys across every control before splining.
• Weight is resistance, then release, then a caught stop. Wade: show what the character is up against (a delay, acceleration from rest) before its strength; strength is a frame count. Elver: more up and down reads as a balloon, not weight; weight is a fall caught abruptly, a bigger hold in the squash, residual jiggle. Heavy air is gravity-true [added physics]; Wade's weighted apex adds hang, for light or cartoony bodies.
• Feet and spine sell every weight shift (jump, hop, landing, lift). Camporota: animate the foot roll in every crouch, it sells the compression; in a big drop the spine drags behind the hips and only the arms drop; first passes overdo the anticipation, so dial it back; a touch-down goes flat "almost in one frame". Elver: on the first airborne frame the toe tip points back to where it left the ground.
• Judge in camera space, at speed. Elver: a motion trail can show a perfect 3D arc that fails on screen. Lazare: the eye goes to the biggest motion, so the non-focus character stays "appropriately still". Project tracks through the shot camera; read the playblast before any metric.
• The base layer is the animation; mocap is precious. Newman: a layer is a time-boxed experiment with marker keys and a protective key; never clean curves on it, merge with Smart Bake, then clean (Elver: only a late global note or an additive tremble, then bake). On mocap fix only the defect asked for, or the cascade ends "not hand key and not mocap"; after a merge, Euler filter, then delete keys down to extremes.
• Lip sync animates sounds, not words. Santos: jaw only first (the muppet pass), then the big five (jaw, two corners, top and bottom lip) for 90%; lead by place of articulation, bilabials on the frame. Lazare: shift every mouth key 1 to 2 frames earlier only when the whole line plays late.
• Polish is triage; review is top down. Elver ranks the notes, spends on the ones that pay, owns every contact frame. Newman grades Intent, Mechanics, Performance, Integration; a playblast does not prove game feel.

Establish first

Input	Why it changes the plan	Default when the brief is silent
Style and destination	squash, stops, closeness to reference: cartoony pushes; live action needs pose squash and no dead stops (Elver); VFX stays near reference (Neistadt)	realistic feature quality
Frame rate	timing numbers, currentUnit	24 fps (film)
Weight and strength	frames of resistance and of overcome (Wade: decide both numbers first)	heavy: resistance beat of 2+ frames, no hang
Rig	control names, IK/FK, spaces, foot roll attribute (map once with listAttr(keyable=True))	hands in IK, no IK/FK or space switches inside a shot (Newman)
Camera	a locked shot camera is the only judge; games also need every angle and the engine	build the shot camera, lock it
Reference, audio	landmarks (contacts, takeoff, apex, landing, blinks, darts) give rhythm, then push (Neistadt)	beat list from the brief
Game metrics	speeds and heights agreed in round numbers before animating (Newman); root motion or in place (Epic)	in place, metrics sheet requested

Workflow

1. Plan in numbers. Beats with frames, the leading part per beat, key categories, contacts, windows (crouch, push, air, impacts), style; A.store_plan(plan). Physical shots: A.air_frames(rise, drop) budgets the air. Dialogue: phrases with subtext and an action verb, ruled sounds (M, B, P, F, V, L, T, D), 2 to 4 tentpoles (Santos, Wade). GATE: frame counts add up.
2. Set up. fps, range, sound, shot camera locked; query the tangent defaults (2027 notes). GATE: mx_validate.validate(profile="shot", rules={"fps": 24}) has no fail.
3. Proxy pass (big, fast or camera-bound moves). A.proxy_boxes(), key translate and lean, air with A.ballistic_keys(), rotation 1 to 2 frames behind (Camporota). The first anticipation is usually too big: A.scale_curve(root, "translateY", 0.8, rest_y, time=crouch). GATE: A.evaluate_gates() on the proxy (ballistic, catch, resistance, push_fastest); proxy_curves.png looked at.
4. Blocking, stepped. A.set_key_defaults("blocking"); A.key_pose(pose, f, fill=ctrls) keys every control on every pose; passes: main, anticipations, overshoots, breakdowns (favor a neighbor, never 50/50), holds (A.key_hold()); A.share_keys(ctrls). Never act from the neutral rig pose (Neistadt). Crouch poses: foot roll keyed, spine dragging, arms hanging (Camporota). GATE: every key category present; stepped playblast (GUI) or tracks.png; write the story it reads, then check silhouettes.
5. Spline pass 1, the core. snap = A.snapshot(ctrls) (the buffer curve); A.to_spline() on COG, spine, legs only; face, eyes, fingers stay stepped (Camporota, Santos). Air gravity-true; broken tangent into a hard landing (Newman); planted feet flat. Mush: A.restore(snap), add poses. Every later key: A.insert_key(), then A.curve_diff() on sampled snapshots is ok outside its two segments (P4). GATE: A.run_gates(plan) ballistic, hang, catch, slide, penetration, foot_roll, spine_drag, heel_to_flat pass; no A.overshoots() through holds.
6. Spline pass 2, overlap. Arms, head, secondary: correlated chains edited together first (Newman), then A.offset_keys() by 1 to 2 frames down the chain. GATE: overlap lags not all zero; pose_to_pose_tell low; tracks clean in camera.
7. Face, if the shot has one. Body first, then the mask (eyes, brows), then the mouth: muppet jaw keyed at A.mouth_keys(phonemes), big five, tongue, connection by A.copy_curve() (nostrils 1 frame behind the corners, dampened). Eyes linear, 2-frame darts; blinks close faster than they open. GATE: A.jaw_report(), A.lip_lag() against A.audio_envelope(), A.blink_report(), A.transitions(); close-ups on tentpoles.
8. Polish, by triage. Fix the top-ranked notes, one section at a time. Contacts and fast moves on ones; peel-off on every takeoff; impacts get a pushed squash and a bigger hold; pops become 3 frames on an arc plus an overshoot; A.retime() tightens a section; moving holds; a motion-blurred render before final (all Elver). GATE: every gate passes (peel_off, impact_hold included), layers merged, no sub-frames, Euler filtered, critique.md on the final playblast.

Variants. Cycle: poses every 3 frames, loop with A.cycle() before polish, offsets inside the cycle keep the period. Game clip: metrics, A.cycle_speed(), loop seam, root rules, then scenario-maya-pipeline-scripting. Mocap: procedures P12; retarget: P13; heavy interactions: P9.

Numbers

Value	Relative to	Source
Gravity 1.703 cm/frame^2 (981/576)	24 fps, scene in cm	physics [added]
Walk keys every 3 frames: contact 1, down 4, pass 7, up 10, contact 13; loop 1 to 25	24-frame cycle	Camporota
Touch-down to flat foot about 1 frame, at most 2; walk arm offsets 0, 1, 2, head 1	every step and landing	Camporota; body digest
Rotation 1 to 2 frames behind translation	proxy and body	Camporota
Keys on ones on fast actions; 2 to 4 frames apart on slow ones	blocking	Newman
Blink close 2 / open 4 (or 3 / 5; big eyes one more)	frames	Elver
Eye dart 2 frames, linear; brows lead lids by 1 to 2, never 5	frames	Elver
Snappy move: 3 frames on an arc plus a small overshoot, never 1	frames	Elver
Global lip shift 1 to 2 frames earlier; opens near full on frame 1	when late at speed	Lazare
Big five = 90% of lip sync; jaw plus corners 50 to 60%	controls	Santos, Elver
Game speeds: walk 2, run 4 to 6, sprint 12 to 15 m/s	stylized player	Newman
Playblast default scale 0.5: pass percent=100	active view	Maya 2027 Help

Quality gates

Measurable (A.run_gates(plan); pure logic A.evaluate_gates), for any jump, hop, landing or weight shift in the plan: fps; heavy air g_ratio 0.8 to 1.25, hang excess at most 1 frame, constant horizontal speed; catch (60%+ of the fall speed gone in 2 frames, decel shorter than recovery), then a 3+ frame hold at the bottom; push fastest; heavy resistance beat of 3+ still frames; every crouch: foot roll moves, spine lags the hips; touch-downs flat within 2 frames; lift-off toe within 30 degrees of the takeoff spot; planted feet at most 0.2 cm/frame, penetration under 0.5 cm; pre-landing stretch; no pops outside impacts; overlap lags; moving end hold; tell under 90% after splining; no sub-frames; no layers at polish. [added] thresholds are toolkit defaults. Visual: A.review_images(plan, out) (headless: curves.png stacked lanes, tracks.png camera-space tracks with onion-skin poses); in the GUI A.playblast_pack() (shot camera plus a no-lights silhouette) and a stepped-preview playblast. Read frames in time order; write the first-view read before the numbers (critique.md).

Common mistakes

Mistake	What it looks like	Fix
Splining before the poses are in	mush, arms tweened through the body	A.restore(snap), add breakdowns stepped
Even spacing, whole body on the same frames	floaty, "hitting poses"	favor neighbors, holds, offset_keys down the chains
First-pass anticipation kept	the crouch upstages the action	A.scale_curve(..., time=crouch) about the rest value
Torso locked to the hips, arms swung back in the crouch	stiff, generic anticipation	spine drags behind the hips, only the arms drop
Feet flat in the crouch, pointing forward at takeoff, slow to flatten on landing	weak compression, no push, slapping feet	foot roll; toe aimed back at the takeoff spot; flat within 1 to 2 frames
Stylized hang on a heavy body	floaty apex	ballistic_keys, flat apex, broken contact tangent
No resistance before the effort	styrofoam weight	2+ frames of strain before the push
Symmetric dip, or a bounce straight out of the squash	light landing	sudden catch, bigger hold, one overshoot, slow recovery
S or bare setKeyframe on a splined curve	neighbors reshape, holds drift	A.insert_key, then A.curve_diff
Spline through a hold	drifting hold	key_hold pillars, flat or plateau sides
Arcs checked on a 3D trail	clean trail, broken arc on screen	camera_track pixel tracks
Lip sync keyed on the sound	late at speed	per-sound lead, then a global shift

Handoffs

Receives from scenario-maya-rigging and scenario-maya-deformation: the rig referenced (never imported), validate(profile="rig") clean, the control list with IK/FK, space and foot roll attributes, a range-of-motion playblast. Rig problems (knee pop, flipping space) go back as a note with frames. Delivers shots to scenario-maya-lighting-rendering: a new saved version, validate(profile="shot") clean, layers merged, helpers deleted (A.delete_helpers()), run_gates JSON with no fail, the final playblast the agent looked at, what was not verified. Game clips to scenario-maya-pipeline-scripting: skeleton baked per clip, clip names and ranges (bookmarks), root rule (in place or root motion), loop seam and speed reports.

Maya 2027 notes

• Default tangent: Auto Span (Legacy) on one doc page, Clamped on another: query keyTangent(q=True, g=True, itt=True). Lock/Free Tangent Weight is now Tangent Length; Butterworth is Smooth Filter (Butterworth).
• Time Slider > Enable Stepped Preview; A.stepped_preview() is the scripted twin. Dope Sheet Time Snap is off since 2025.1 and scaleKey leaves sub-frames: A.snap_subframes().
• Ghost Editor and Motion Trail Editor sit under Visualize; ghosting a skinned mesh needs Cached Playback (disabled by motion blur, Trax, classic dynamics).
• Playblast needs a model panel (GUI via mx_bridge); in mayapy use review_images or Arnold stills.
• Sequencer (ex Camera Sequencer): lock every camera. HumanIK bakes from its own window, not Bake Simulation. Time Editor clips never mix with animation layers. Blue Pencil replaced Grease Pencil.

References

• references/expert-notes.md: principles and numbers by expert, timestamps, deciding conditions. Load to choose an approach or write notes.
• references/procedures.md: the mx_anim API and full procedures with test paths. Load before writing code.
• references/critique.md: review rubric (first-view read, four buckets), director lingo, note format. Load at every gate.
• references/gui-paths.md: menus, hotkeys, editor settings. Load for a computer-use agent or a human.
• references/sources.md: every source, credential, URL and best timestamp.