s3d-api

S3D Agent Skill

You are an agent that builds, analyses, and queries SkyCiv Structural 3D (S3D) structural models via the SkyCiv API. This skill covers the full s3d_model JSON schema and every function in the S3D.model, S3D.results, S3D.file, and S3D.SB namespaces.

Prerequisite: Always begin a session with S3D.session.start as the first function. See the skyciv-core skill for auth, options, and the request/response envelope.

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The s3d_model Object

The s3d_model is the JSON representation of a structural model. It is passed to S3D.model.set.

{
  "settings": { ... },
  "nodes": { ... },
  "members": { ... },
  "plates": { ... },
  "meshed_plates": { ... },
  "sections": { ... },
  "materials": { ... },
  "supports": { ... },
  "settlements": { ... },
  "point_loads": { ... },
  "moments": { ... },
  "distributed_loads": { ... },
  "pressures": { ... },
  "area_loads": { ... },
  "self_weight": { ... },
  "load_combinations": { ... },
  "load_cases": { ... },
  "groups": { ... },
  "gridlines_and_elevations": [ ... ]
}

All objects use integer-keyed dictionaries (e.g. "1": { ... }, "2": { ... }), except gridlines_and_elevations, which is a plain array.

Tip: To inspect a model as JSON, open it in SkyCiv S3D and use File → Export → SkyCiv File (JSON for API). To test JSON, use File → Import → SkyCiv File (JSON for API).

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settings

Key	Type	Accepts	Default
units	string or object	"imperial", "metric", or detailed object	varies
vertical_axis	string	"Y", "Z"	"Y"
precision	string	"fixed", "exponential"	"fixed"
precision_values	integer	1–15	—
evaluation_points	integer	3–50	—
solver_timeout	integer	seconds	—
non_linear_tolerance	string	e.g. "1" (= 1%)	—
non_linear_theory	string	"small", "finite"	"small"
auto_stabilize_model	boolean	—	false
member_offsets_axis	string	"global", "local"	"local"
dynamic_modes	integer	positive integer	5