Layer 3D Generation

Overview

3D on Layer is a chain of separate use cases, not one call. Generate the mesh, then remesh, retexture, rig, or animate it as the deliverable requires. Each stage is its own filter.use_case and its own run, and each takes the previous stage's output file_id as input.

The loop and the spend gate are in the layer skill. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add layerai/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

Start from an image

image_to_3d is the stronger path whenever the design is settled or settleable. A generated mesh inherits its silhouette and surface detail from the reference, so approving a still first with layer-image costs one cheap image run and removes most of the iteration from an expensive 3D one.

The reference image should show the subject clean: isolated on a plain background, lit evenly, in a three-quarter view that reveals depth. A dramatic, heavily shadowed key art frame makes a worse reference than a plain orthographic-ish view, because the model reads shadow as geometry.

text_to_3d is right when nothing exists yet and the shape is simple or generic enough to describe.

Say what the mesh is for

The engine target changes the request, so state it rather than accepting defaults:

• Topology: quad_mesh where the asset will be sculpted, deformed, or subdivided downstream. Triangles are fine for a static prop that ships as-is.
• Budget: a face_limit reflecting the platform. A hero prop on desktop and a background prop on mobile are different requests, and remeshing later costs another run.
• Surfaces: pbr_materials and include_textures when the asset goes into a lit scene. Without them you get geometry and a flat surface, which reads as broken in an engine.

The per-model inference schema is the authority on which of these apply, so read get_base_model before composing the run.

Describing geometry

3D prompts reward structural language and ignore atmosphere. Lighting, mood, and camera belong to an image prompt and do nothing here, because the mesh carries no lighting.

Name the form: overall silhouette, proportions, how parts join, surface material, and the level of detail. "Squat clay cooking pot, wide rounded belly, short flared neck, two small looped handles at the shoulder, hand-thrown surface with visible ridges" describes a mesh. "Beautiful ancient pot, dramatic lighting" describes a photograph and will produce a generic one.

Symmetry and closed forms generate reliably. Thin protrusions, chains, cloth, and hair are where generated meshes fail, so plan to model those separately or accept them as fused geometry.

Rigging and animation

rig produces a skeleton and weights, and it expects a mesh in a neutral, limbs-apart rest pose. A mesh generated in a dynamic action pose rigs badly, so generate the rest pose first and animate into the action.

animate needs a rigged mesh, so the two run in order. Where a model offers named motion presets, those are more reliable than describing the motion in prose.

Worked example

"Turn this approved prop concept into a game-ready mesh for mobile."

1. The concept exists from an earlier image run and already carries a file_id.
2. list_base_models with filter.use_case: "image_to_3d" and filter.capabilities: {textures: true} (an object of booleans, not a list of names). Take the first result, then get_base_model for the fields it accepts.
3. estimate_forge_price with the concept as image_to_3d input, pbr_materials and include_textures on, quad_mesh off for a static prop, and a face_limit matched to mobile. 3D runs are expensive, so expect this to clear 20 CUs and ask before proceeding.
4. Execute, poll at poll_interval_seconds.
5. Inspect the result before chaining. If the silhouette is right but the count is too high, the next run is remesh on the output file_id, not a regenerate.

Common mistakes

• Using text_to_3d when concept art exists or could be generated cheaply first.
• Feeding a dramatic, shadow-heavy key art frame as the 3D reference.
• Writing an image prompt (lighting, mood, camera) for a mesh.
• Leaving topology, budget, and materials unspecified, then remeshing in a second paid run.
• Rigging a mesh generated in an action pose.
• Regenerating from scratch when remesh or retexture would fix the actual defect.
• Expecting clean thin geometry such as chains, straps, or hair from a generated mesh.