Meshy 3D generation

Meshy is a hosted generative-3D service. You give it text or images; it returns a textured mesh (GLB/FBX/OBJ/USDZ/STL/3MF), with optional PBR maps, remeshing, UV, auto-rigging, and library animations. Everything runs as asynchronous jobs: you POST a task, get a task ID, then poll, stream (SSE), or receive a webhook until SUCCEEDED.

This skill covers driving Meshy well: choosing the right generation mode, writing prompts that separate geometry from texture, controlling topology and poly count, texturing and re-texturing, rigging and animating, exporting into a game/film/print pipeline, and judging whether the output is usable.

Evidence labels used below

• [Doc] — stated in official Meshy documentation, API reference, or help center (URLs in Sources). Volatile items carry a verification date.
• [1P-claim] — a first-party Meshy claim (marketing/blog/help) not independently verified. Treat as a claim, not a guarantee.
• [Heuristic] — production judgment from how generative-3D pipelines behave; verify against your own output.

Volatile facts (model IDs, credit costs, limits, formats) were verified 2026-07-10 against docs.meshy.ai. Re-check the changelog and pricing pages before quoting numbers to a user, because Meshy ships model versions and adjusts credit costs and promotions frequently.

When to use Meshy — and when not to

Use Meshy when you need:

• A single, coherent prop, character, or creature fast from a prompt or a reference image (concept-to-asset, game jam, previz, background dressing, crowd fillers, marketplace assets, 3D-print blanks). [Heuristic]
• A textured starting mesh you will clean up downstream rather than a final production hero asset. [Heuristic]
• Bulk asset generation where throughput and cost per asset matter more than authored topology. [Heuristic]

Do not reach for Meshy when:

• You need exact real-world dimensions or CAD tolerances (mechanical parts, enclosures, mounting brackets). Generative meshes are approximate; use CAD. [Heuristic]
• You need guaranteed-watertight, manifold geometry for manufacturing. Meshy offers printability analysis/repair and remesh, but does not guarantee a manifold result; validate in a slicer/mesh-repair tool. [Heuristic]
• You must edit the geometry of an existing hand-authored asset — Meshy regenerates, it does not surgically edit your mesh.
• The subject is a full scene (room, environment, multiple interacting objects). Text-to-3D and image-to-3D reconstruct one subject best; build the scene from separately generated parts in your engine. [Doc/Heuristic]
• You require clean animation-ready quad topology with edge loops around deformation areas authored to spec. Meshy's quad remesh is quad-dominant reconstruction, not artist-placed edge flow. [Heuristic]
• Licensing forbids AI-generated assets, or your reference images are copyrighted in a way that would taint ownership (see Rights & licensing).

Model versions and mode selection

ai_model accepts meshy-6, meshy-5, or latest; latest resolves to the current generation, which is Meshy-6 as of 2026-07-10. [Doc, verified 2026-07-10] Meshy-4 was retired and its API requests are no longer supported. [Doc] Pin an explicit version (meshy-5 or meshy-6) when you need reproducible behavior across a batch; use latest only when you want Meshy's newest default and can tolerate behavior changes. [Heuristic]

model_type selects standard (default) or lowpoly. [Doc] lowpoly produces stylized low-polygon output and, per the image-to-3D reference, overrides remesh, PBR, and poly-count settings, so do not combine it with fine topology control. [Doc, verified 2026-07-10]

Meshy-6-only / latest-only texture features: hd_texture (4K base color), remove_lighting (bakes out captured shadows/highlights), and, for image-to-3D, image_enhancement. [Doc, verified 2026-07-10]

Deprecated parameters — do not use

• art_style (Text-to-3D preview) — unsupported by Meshy-6; formerly realistic / sculpture. [Doc]
• symmetry_mode — no longer functional. [Doc]
• is_a_t_pose — replaced by pose_mode (a-pose, t-pose, or ""). [Doc]
• Remesh resize_height, resize_longest_side, auto_size, origin_at — documented as deprecated on the remesh endpoint. [Doc]

Passing deprecated params generally no-ops; prefer the current replacements so your integration survives cleanups.

The async job model

Base URL https://api.meshy.ai/openapi/v1 (Text-to-3D uses the v2 path /openapi/v2/text-to-3d; other endpoints are v1). [Doc, verified 2026-07-10]

Auth Bearer token: Authorization: Bearer $MESHY_API_KEY. Create the key at meshy.ai/settings/api; it is shown once — store it (env var, secret manager), never hardcode. API access requires a Pro tier or higher subscription; the free tier cannot create API tasks. [Doc]

Task lifecycle Every generation POST returns a task id immediately. Status progresses PENDING → IN_PROGRESS → SUCCEEDED (or FAILED / CANCELED), with progress 0–100 and, while PENDING, preceding_tasks (queue position). [Doc]

Three ways to learn a task finished [Doc]:

1. Poll GET /openapi/v1/<endpoint>/:id on an interval until terminal status. Simplest; use a backoff (e.g. 2–5 s) and stop on SUCCEEDED/FAILED/CANCELED. [Heuristic]
2. Stream GET .../:id/stream — SSE message/error events; partial frames carry only id, progress, status.
3. Webhook — register a callback to be notified on completion. Prefer for server integrations to avoid poll load. [Heuristic]

Rate limits (verified 2026-07-10) [Doc]: 20 requests/second on Pro, Premium, Ultra, Studio; 100/s on Enterprise. Concurrent "queue" tasks (Text to 3D, Image to 3D, Text to Texture, Remesh): Pro 10, Studio 20, Premium 30, Ultra 100, Enterprise 50 (customizable). Exceeding rps → 429 RateLimitExceeded; exceeding concurrency → 429 NoMoreConcurrentTasks. Design a client-side concurrency gate to your tier's queue limit and retry 429s with backoff. [Heuristic]

Error codes [Doc]: 400 bad/invalid params or over-limit prompt, 401 bad key, 402 insufficient credits, 404 unknown task, 429 rate/queue. Failed tasks return task_error.message; consumed_credits is 0 on failure.

Asset retention Generated files are retained ~3 days on non-Enterprise plans. [Doc, verified 2026-07-10] Download and re-host output URLs promptly; do not treat Meshy CDN URLs as permanent storage. [Heuristic]

Text-to-3D: the two-step preview → refine workflow

Text-to-3D is deliberately two calls so you can approve geometry before paying to texture it. [Doc]

Step 1 — preview (geometry only). POST /openapi/v2/text-to-3d with mode: "preview" and a prompt (≤ 600 chars). Key controls: [Doc, verified 2026-07-10]

• ai_model meshy-6 | meshy-5 | latest
• model_type standard | lowpoly
• topology triangle (default) | quad
• target_polycount 100–300,000 (default 30,000); or decimation_mode 1–4 (adaptive; overrides target_polycount)
• should_remesh (default false on Meshy-6, true otherwise)
• pose_mode "" | a-pose | t-pose — request an A/T pose when the mesh will be rigged
• target_formats any of glb, obj, fbx, stl, usdz, 3mf (all except 3mf by default)
• auto_size + origin_at (bottom/center) for real-world scale
• alpha_thumbnail, moderation

Step 2 — refine (texture). POST again with mode: "refine" and preview_task_id = the succeeded preview's ID. Texture controls: enable_pbr (metallic/roughness/normal/emission maps), hd_texture (4K base color, Meshy-6), texture_prompt (≤ 600 chars), texture_image_url (URL or base64 style reference), remove_lighting (default true, Meshy-6). [Doc]

Outputs include model_urls (per format), texture_urls (array with base_color and, under PBR, metallic/normal/roughness/emission), thumbnail_url. [Doc]

Because these are separate billed steps, iterate cheaply: regenerate or re-prompt at preview until the silhouette/topology is right, then refine once. [Heuristic]

Image-to-3D and Multi-Image-to-3D

POST /openapi/v1/image-to-3d reconstructs one subject from one image (image_url as public URL or base64 data URI, .jpg/.jpeg/.png), or from a prior text-to-image / image-to-image task via input_task_id. [Doc] Texturing and topology params mirror text-to-3D refine plus: should_texture (default true), image_enhancement (Meshy-6, default true), save_pre_remeshed_model, multi_view_thumbnails. [Doc, verified 2026-07-10]

POST /openapi/v1/multi-image-to-3d accepts 1–4 images of the same object from different angles (image_urls) for better reconstruction. [Doc]

Reference-image guidance [Heuristic]:

• Use a clean subject on a plain background, well lit, minimal occlusion, the whole object in frame. Busy backgrounds bleed into reconstruction.
• For multi-image, shoot/collect consistent, non-conflicting views (e.g. front, side, back) of the same object at the same scale and lighting; contradictory views produce fused or averaged geometry.
• Image-to-3D infers unseen sides — expect invention on the back of a single-front-view input; add views (multi-image) to constrain it.
• texture_prompt and texture_image_url guide texture, not shape; text is prioritized if both are given (per the image-to-3D reference). [Doc]

Texturing, PBR, and re-texturing

Texture quality is separable from geometry. Options across the texturing-capable endpoints [Doc]:

• enable_pbr — produce metallic/roughness/normal (+ emission on Meshy-6) maps for physically based rendering in Unity/Unreal/Blender. Leave off for flat base-color-only assets.
• hd_texture — 4K (4096²) base color; PBR maps stay 2K. Meshy-6/latest only. Use for hero assets seen close up; skip for background props to save credits/time. [Doc/Heuristic]
• remove_lighting — bakes out captured highlights/shadows so your engine can relight; default true, Meshy-6/latest. Keep on when the asset must react to scene lighting. [Doc]

Retexture / restyle an existing mesh: POST /openapi/v1/retexture with input_task_id or model_url (.glb/.gltf/.obj/.fbx/.stl) plus a style via text_style_prompt (≤ 600 chars) or image_style_url; if both are given, image_style_url wins. [Doc, verified 2026-07-10] Key flag: enable_original_uv — reuse the model's existing UV layout instead of generating new UVs (preserves existing textures; if the model has no UVs, quality suffers). Also supports enable_pbr, hd_texture, remove_lighting, ai_model, target_formats. [Doc] Use retexture to re-skin one mesh into many variants (color/material swaps) without regenerating geometry. [Heuristic]

Topology, poly count, and remesh

• topology: triangle — default; fine for static props, rendering, and most engine import. topology: quad — quad-dominant reconstruction, friendlier to subdivision and some DCC workflows, but not artist-authored edge loops. [Doc/Heuristic]
• target_polycount (100–300,000): pick to budget. As rough starting targets [Heuristic]: background/mobile props ~1k–10k; standard game assets ~10k–50k; film/close-up hero or 3D-print masters higher (tens–hundreds of thousands). These are budgets, not quality guarantees — a high count can still hide bad topology.
• decimation_mode 1–4 gives adaptive reduction and overrides target_polycount. [Doc]

Remesh POST /openapi/v1/remesh re-topologizes/exports an existing task or uploaded model (input_task_id or model_url; .glb/.gltf/.obj/.fbx/.stl). Params: target_formats (adds blend), topology, target_polycount (100–300,000, default 30,000), decimation_mode 1–4. [Doc, verified 2026-07-10] Reach for remesh when the raw generation has too many faces, messy topology, or you need a watertight-oriented mesh for printing, and before rigging if the mesh exceeds 300,000 faces (the rigging cap). [Doc]

Recommended post-processing order (Meshy's own guidance): Remesh → Unwrap UV → AI Texturing → Rigging → Animate → export. [Doc]

Rigging and animation

POST /openapi/v1/rigging rigs a textured humanoid GLB. [Doc, verified 2026-07-10] Requirements and params:

• Input: input_task_id (a textured model task) or model_url (GLB / .glb only, public URL or data URI). [Doc]
• height_meters (default 1.7, must be positive); optional texture_image_url (UV-unwrapped base-color PNG). [Doc]
• Constraints: humanoid with clearly defined limbs; character must face the +Z axis (glTF forward); ≤ 300,000 faces when using input_task_id (remesh first if larger). Untextured meshes, non-humanoids, and unclear limb structure are unsuitable. [Doc]
• Output: rigged character in FBX and GLB, plus basic walk/run animations (skinned and armature-only variants). [Doc]

Animation POST /openapi/v1/animations applies a library clip to a rigged model via action_id. The library holds 500+ animations (categories like DailyActions, WalkAndRun, Fighting, Dancing, BodyMovements); look up the action_id in the Animation Library reference. [Doc, verified 2026-07-10] For custom or non-humanoid motion, rig/animate in Blender/Maya instead. [Heuristic]

Export and engine import

Formats: glb, obj, fbx, stl, usdz, 3mf (remesh adds blend). Request only what you need via target_formats to keep responses small. [Doc]

Practical routing [Heuristic]:

• Unity / Unreal / three.js / web: glb (or fbx for skinned rigs). GLB carries PBR maps in one file. Assign metallic/roughness/normal/ emission from texture_urls if you re-import maps separately.
• Blender / DCC editing: glb or, from remesh, blend; fbx for rigs.
• AR (iOS Quick Look): usdz.
• 3D printing: stl or 3mf; run remesh first for topology/scale, then validate manifoldness and wall thickness in a slicer.
• Set real scale with auto_size + origin_at, or height_meters at rigging, so the asset imports at usable size rather than arbitrary units.

Prompt construction: separate geometry from texture

Geometry is decided at preview / generation; surface look is decided at refine / texture. Write for each stage. [Doc/Heuristic]

Geometry prompt (subject + form + a few concrete features). One object, ~3–6 key details. Name the object type first, then defining shape/parts, then scale and intended use. Prefer singular nouns — plurals ("warriors") invite fused or extra limbs. Avoid full scenes, abstract concepts, and micro-detail like individual hair strands. [1P-claim, Meshy prompt guide]

Texture prompt (materials, colors, finish, style) belongs in texture_prompt / retexture: e.g. "brushed brass and dark oak, matte finish" rather than restating the shape. Concrete material words ("smooth gold metal") beat vague praise ("looks beautiful"). [1P-claim]

Render-quality buzzwords ("8k, Unreal Engine, Octane, cinematic lighting") are image-model habits; they mainly affect Meshy's texture/albedo, not geometry — use them in the texture stage, not to try to improve the mesh. [Heuristic]

Quality review: is the mesh usable?

Inspect before accepting. Check [Heuristic]:

• Silhouette / proportions from multiple angles (use multi_view_thumbnails or open the GLB). Generative meshes often look right from the front and wrong from behind or top.
• Topology & poly count — is it within budget? Is it a dense blob that needs remesh? quad requested where subdivision/deformation is needed?
• UVs & seams — visible seams or stretched texels? If you must hand-paint, Unwrap UV first; for restyles, enable_original_uv preserves layout.
• Watertightness / manifold for print — do not assume; verify in a mesh tool. Meshy provides printability analysis/repair but no guarantee. [Doc]
• Texture artifacts — baked-in lighting (turn on remove_lighting), smeared or hallucinated detail on unseen faces, resolution (upgrade to hd_texture only where it shows).
• Rig readiness — humanoid, +Z facing, ≤ 300k faces, in A/T pose, textured before you send it to rigging.
• Symmetry/limbs — extra/fused limbs or asymmetry from ambiguous prompts or conflicting reference views → re-prompt or add views.

Iteration and repair workflow

1. Preview cheaply, refine once. Approve geometry before texturing. [Doc]
2. Wrong shape? Re-prompt geometry (singular noun, clearer form, add reference image / more views). Small wording changes shift results. [1P]
3. Right shape, wrong surface? Keep the mesh; re-run refine/retexture with a better texture_prompt or image_style_url. Don't regenerate geometry to fix a texture. [Heuristic]
4. Too heavy / bad topology? Remesh to target poly count / quad. [Doc]
5. Seams / hand-paint needed? Unwrap UV before texturing. [Doc]
6. Needs animation? Ensure textured + A/T pose + ≤ 300k faces (remesh if not) → rig → animate by action_id. [Doc]
7. Batch: gate concurrency to your tier's queue limit; retry 429s; download outputs within the retention window. [Heuristic]

Credits and pricing (verified 2026-07-10)

API usage bills per operation in credits (Pro+ subscription required). Costs depend on model: Meshy-6 and low-poly cost more than legacy models. [Doc]

Operation	Meshy-6 / low-poly	Other models
Text-to-3D preview	20	5
Text-to-3D refine (texture)	10	10
Image-to-3D (no texture / with texture)	20 / 30	5 / 15
Multi-Image-to-3D (no texture / with texture)	20 / 30	5 / 15
Retexture / Text-to-Texture	10	10
Remesh	5	5
Auto-rigging	5	5
Animation	3	3

[Doc, docs.meshy.ai/en/api/pricing, verified 2026-07-10] A full textured Meshy-6 text-to-3D via API is therefore ~30 credits (20 preview + 10 refine). Failed tasks charge 0. Promotions and per-model costs change — re-read the pricing page before quoting. Web-app pricing can differ from API per-operation pricing. [Doc/Heuristic]

Rights and licensing (verified 2026-07-10)

• Paid plans: you retain full private ownership of assets you create and may distribute/sell them, provided (a) you did not use materials that infringe others' copyright as input, and (b) you do not publish the model to the public Meshy Community — publishing to the community removes that private ownership protection. [Doc, Meshy help center]
• Free plan: models are licensed CC BY 4.0 — you may use, modify, and even sell them, but must give attribution (Meshy suggests "Model created with Meshy – CC BY 4.0 License"). [Doc]
• Input hygiene: feeding copyrighted/trademarked reference images (a character, a logo, a real person) can taint ownership and create infringement risk regardless of plan. Use references you have rights to. [Heuristic]
• Confirm current terms at meshy.ai/terms-of-use before shipping commercially; these terms are volatile.

Complete examples (illustrative — not fixed formulas)

Example A — Textured game prop, text-to-3D, Meshy-6

Intent: a game-ready treasure chest, ~20k tris, PBR, GLB for Unity.

Preview (geometry):

curl -s https://api.meshy.ai/openapi/v2/text-to-3d \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{
    "mode": "preview",
    "prompt": "a sturdy wooden treasure chest with iron banding and a domed lid, ornate lock plate, medieval fantasy style",
    "ai_model": "meshy-6",
    "topology": "triangle",
    "target_polycount": 20000,
    "target_formats": ["glb"]
  }'
# -> { "result": "<preview_id>" }  then poll GET /openapi/v2/text-to-3d/<preview_id>

Refine (texture) once preview is SUCCEEDED:

curl -s https://api.meshy.ai/openapi/v2/text-to-3d \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{
    "mode": "refine",
    "preview_task_id": "<preview_id>",
    "enable_pbr": true,
    "texture_prompt": "aged oak planks, dark iron fittings, worn brass lock, matte finish"
  }'

Why: geometry words in preview, material words in the texture stage; PBR for engine relighting; poly budget set at preview. Expected: a chest GLB with base-color + metallic/roughness/normal maps. Failure modes: over-detailed prompt → mushy carving; skipping enable_pbr → flat look in Unreal. Variation: add hd_texture: true for a close-up hero chest.

Example B — Character from concept art, then rig + walk

Intent: reference image → riggable humanoid → walking animation.

# 1) multi-image reconstruction (front + side + back of the SAME character)
curl -s https://api.meshy.ai/openapi/v1/multi-image-to-3d \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{ "image_urls": ["https://.../front.png","https://.../side.png","https://.../back.png"],
        "ai_model":"meshy-6", "should_texture": true, "pose_mode": "a-pose" }'
# poll -> SUCCEEDED, note <model_task_id>; confirm faces <= 300000 (remesh if not)

# 2) rig the textured humanoid
curl -s https://api.meshy.ai/openapi/v1/rigging \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{ "input_task_id": "<model_task_id>", "height_meters": 1.8 }'
# poll -> <rig_task_id>

# 3) apply a walk animation by action_id (look up in Animation Library)
curl -s https://api.meshy.ai/openapi/v1/animations \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{ "input_task_id": "<rig_task_id>", "action_id": 1 }'

Why: a-pose at generation makes rigging reliable; multi-image constrains the back so the rig binds a real mesh, not a hallucinated one; rig needs a textured humanoid ≤ 300k faces facing +Z. Failure modes: single front image → bad back + failed rig; non-humanoid subject → rig rejects it; > 300k faces → remesh first.

Example C — Restyle one mesh into color variants (retexture)

Intent: reuse an approved sword mesh as three material variants without regenerating geometry.

curl -s https://api.meshy.ai/openapi/v1/retexture \
  -H "Authorization: Bearer $MESHY_API_KEY" -H 'Content-Type: application/json' \
  -d '{ "input_task_id": "<sword_task_id>",
        "text_style_prompt": "corroded bronze blade, verdigris patina, leather-wrapped grip",
        "enable_original_uv": true, "enable_pbr": true }'

Why: enable_original_uv preserves the existing UV layout so variants stay UV-consistent; only the surface changes; 10 credits per variant vs. re-running a full generation. Failure mode: model lacking UVs → weaker result (unwrap first).

Sources (verified 2026-07-10)

• Text-to-3D API — https://docs.meshy.ai/en/api/text-to-3d
• Image-to-3D API — https://docs.meshy.ai/en/api/image-to-3d
• Multi-Image-to-3D API — https://docs.meshy.ai/en/api/multi-image-to-3d
• Retexture / Text-to-Texture API — https://docs.meshy.ai/en/api/retexture
• Remesh API — https://docs.meshy.ai/en/api/remesh
• Rigging & Animation API — https://docs.meshy.ai/en/api/rigging-and-animation
• Animation Library — https://docs.meshy.ai/en/api/animation-library
• Quickstart / auth — https://docs.meshy.ai/en/api/quick-start
• Rate limits — https://docs.meshy.ai/en/api/rate-limits
• API pricing — https://docs.meshy.ai/en/api/pricing
• Changelog — https://docs.meshy.ai/en/api/changelog
• Post-processing decision guide — https://docs.meshy.ai/en/webapp/guides/choosing/post-processing
• Prompt best practices — https://help.meshy.ai/en/articles/11972484-best-practices-for-creating-a-text-prompt and https://www.meshy.ai/blog/meshy-5-text-to-3d
• Ownership — https://help.meshy.ai/en/articles/10137554-what-is-the-ownership-of-the-generated-models
• Commercial use — https://help.meshy.ai/en/articles/9992001-can-i-use-my-generated-assets-for-commercial-projects
• Credit costs (help) — https://help.meshy.ai/en/articles/10000507-how-many-credits-does-each-generation-task-cost
• Plans/pricing — https://www.meshy.ai/pricing