Skip to main content
Glama

Sample Object Transform at Frames

sample_transform

Evaluate an object's transform at requested frames to verify Alembic, constraint, or Xpresso-driven animation without writing a custom Python sampler.

Instructions

Evaluate the scene at each requested frame and return the object's transform. Useful to verify alembic / constraint / xpresso-driven animation without writing a bespoke exec_python sampler.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
fpsNoTime base override (default: doc fps).
spaceNoTransform space (default "global").
formatNoOutput format: "off_rot" returns pos+rot(HPB radians); "matrix" returns 4x3 rows.
framesYesFrames to sample (1..500). The scene is evaluated at each frame via ExecutePasses.
handleYesTarget object handle (must resolve to a BaseObject).
restore_timeNoRestore the original playhead after sampling (default true).

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed3 schema fields changedv0.5.1
    • removedInput schema / definitions
      Removed value: -{
      -  "__schema0": {
      -    "anyOf": [
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "object",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          },
      -          "path": {
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "render_data",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "name"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "take",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "name"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "material",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "name"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "layer",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "name"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "tag",
      -            "type": "string"
      -          },
      -          "object": {
      -            "type": "string"
      -          },
      -          "object_path": {
      -            "type": "string"
      -          },
      -          "tag_name": {
      -            "type": "string"
      -          },
      -          "type_id": {
      -            "maximum": 9007199254740991,
      -            "minimum": -9007199254740991,
      -            "type": "integer"
      -          }
      -        },
      -        "required": [
      -          "kind"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "video_post",
      -            "type": "string"
      -          },
      -          "render_data": {
      -            "type": "string"
      -          },
      -          "type_id": {
      -            "maximum": 9007199254740991,
      -            "minimum": -9007199254740991,
      -            "type": "integer"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "render_data",
      -          "type_id"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "index": {
      -            "maximum": 9007199254740991,
      -            "minimum": 0,
      -            "type": "integer"
      -          },
      -          "kind": {
      -            "const": "shader",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          },
      -          "owner": {
      -            "allOf": [
      -              {
      -                "$ref": "#/definitions/__schema0"
      -              }
      -            ]
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "owner"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "id": {
      -            "type": "string"
      -          },
      -          "kind": {
      -            "const": "gv_node",
      -            "type": "string"
      -          },
      -          "name": {
      -            "type": "string"
      -          },
      -          "tag": {
      -            "allOf": [
      -              {
      -                "$ref": "#/definitions/__schema0"
      -              }
      -            ]
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "tag"
      -        ],
      -        "type": "object"
      -      },
      -      {
      -        "properties": {
      -          "kind": {
      -            "const": "plugin_options",
      -            "type": "string"
      -          },
      -          "plugin_id": {
      -            "anyOf": [
      -              {
      -                "maximum": 9007199254740991,
      -                "minimum": -9007199254740991,
      -                "type": "integer"
      -              },
      -              {
      -                "type": "string"
      -              }
      -            ]
      -          },
      -          "plugin_type": {
      -            "enum": [
      -              "command",
      -              "object",
      -              "tag",
      -              "material",
      -              "shader",
      -              "video_post",
      -              "scene_loader",
      -              "scene_saver",
      -              "bitmap_loader",
      -              "bitmap_saver",
      -              "tool",
      -              "preference",
      -              "node",
      -              "sculpt_brush"
      -            ],
      -            "type": "string"
      -          }
      -        },
      -        "required": [
      -          "kind",
      -          "plugin_id"
      -        ],
      -        "type": "object"
      -      }
      -    ]
      -  }
      -}
    • removedInput schema / properties / handle / allOf
      Removed value: -[
      -  {
      -    "$ref": "#/definitions/__schema0"
      -  }
      -]
    • addedInput schema / properties / handle / anyOf
      Added value: +[
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "object",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "path": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "render_data",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "take",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "material",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "layer",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "tag",
      +        "type": "string"
      +      },
      +      "object": {
      +        "type": "string"
      +      },
      +      "object_path": {
      +        "type": "string"
      +      },
      +      "tag_name": {
      +        "type": "string"
      +      },
      +      "type_id": {
      +        "maximum": 9007199254740991,
      +        "minimum": -9007199254740991,
      +        "type": "integer"
      +      }
      +    },
      +    "required": [
      +      "kind"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "video_post",
      +        "type": "string"
      +      },
      +      "render_data": {
      +        "type": "string"
      +      },
      +      "type_id": {
      +        "maximum": 9007199254740991,
      +        "minimum": -9007199254740991,
      +        "type": "integer"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "render_data",
      +      "type_id"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "plugin_options",
      +        "type": "string"
      +      },
      +      "plugin_id": {
      +        "anyOf": [
      +          {
      +            "maximum": 9007199254740991,
      +            "minimum": -9007199254740991,
      +            "type": "integer"
      +          },
      +          {
      +            "type": "string"
      +          }
      +        ]
      +      },
      +      "plugin_type": {
      +        "enum": [
      +          "command",
      +          "object",
      +          "tag",
      +          "material",
      +          "shader",
      +          "video_post",
      +          "scene_loader",
      +          "scene_saver",
      +          "bitmap_loader",
      +          "bitmap_saver",
      +          "tool",
      +          "preference",
      +          "node",
      +          "sculpt_brush"
      +        ],
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "plugin_id"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "index": {
      +        "maximum": 9007199254740991,
      +        "minimum": 0,
      +        "type": "integer"
      +      },
      +      "kind": {
      +        "const": "shader",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "owner": {
      +        "additionalProperties": {},
      +        "description": "Handle of the shader's owner (material, object, tag, video_post, or shader).",
      +        "properties": {
      +          "kind": {
      +            "type": "string"
      +          }
      +        },
      +        "required": [
      +          "kind"
      +        ],
      +        "type": "object"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "owner"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "id": {
      +        "type": "string"
      +      },
      +      "kind": {
      +        "const": "gv_node",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "tag": {
      +        "properties": {
      +          "kind": {
      +            "const": "tag",
      +            "type": "string"
      +          },
      +          "object": {
      +            "type": "string"
      +          },
      +          "object_path": {
      +            "type": "string"
      +          },
      +          "tag_name": {
      +            "type": "string"
      +          },
      +          "type_id": {
      +            "maximum": 9007199254740991,
      +            "minimum": -9007199254740991,
      +            "type": "integer"
      +          }
      +        },
      +        "required": [
      +          "kind"
      +        ],
      +        "type": "object"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "tag"
      +    ],
      +    "type": "object"
      +  }
      +]
  2. Changed1 schema field changedv0.4.3
    • changedInput schema / definitions / __schema0 / anyOf
      Previous value: -[
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "object",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      },
      -      "path": {
      -        "type": "string"
      -      }
      -    },
      -    "required": [
      -      "kind"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "render_data",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "name"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "take",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "name"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "material",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "name"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "tag",
      -        "type": "string"
      -      },
      -      "object": {
      -        "type": "string"
      -      },
      -      "object_path": {
      -        "type": "string"
      -      },
      -      "tag_name": {
      -        "type": "string"
      -      },
      -      "type_id": {
      -        "maximum": 9007199254740991,
      -        "minimum": -9007199254740991,
      -        "type": "integer"
      -      }
      -    },
      -    "required": [
      -      "kind"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "video_post",
      -        "type": "string"
      -      },
      -      "render_data": {
      -        "type": "string"
      -      },
      -      "type_id": {
      -        "maximum": 9007199254740991,
      -        "minimum": -9007199254740991,
      -        "type": "integer"
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "render_data",
      -      "type_id"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "index": {
      -        "maximum": 9007199254740991,
      -        "minimum": 0,
      -        "type": "integer"
      -      },
      -      "kind": {
      -        "const": "shader",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      },
      -      "owner": {
      -        "allOf": [
      -          {
      -            "$ref": "#/definitions/__schema0"
      -          }
      -        ]
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "owner"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "id": {
      -        "type": "string"
      -      },
      -      "kind": {
      -        "const": "gv_node",
      -        "type": "string"
      -      },
      -      "name": {
      -        "type": "string"
      -      },
      -      "tag": {
      -        "allOf": [
      -          {
      -            "$ref": "#/definitions/__schema0"
      -          }
      -        ]
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "tag"
      -    ],
      -    "type": "object"
      -  },
      -  {
      -    "properties": {
      -      "kind": {
      -        "const": "plugin_options",
      -        "type": "string"
      -      },
      -      "plugin_id": {
      -        "anyOf": [
      -          {
      -            "maximum": 9007199254740991,
      -            "minimum": -9007199254740991,
      -            "type": "integer"
      -          },
      -          {
      -            "type": "string"
      -          }
      -        ]
      -      },
      -      "plugin_type": {
      -        "enum": [
      -          "command",
      -          "object",
      -          "tag",
      -          "material",
      -          "shader",
      -          "video_post",
      -          "scene_loader",
      -          "scene_saver",
      -          "bitmap_loader",
      -          "bitmap_saver",
      -          "tool",
      -          "preference",
      -          "node",
      -          "sculpt_brush"
      -        ],
      -        "type": "string"
      -      }
      -    },
      -    "required": [
      -      "kind",
      -      "plugin_id"
      -    ],
      -    "type": "object"
      -  }
      -]New value: +[
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "object",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "path": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "render_data",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "take",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "material",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "layer",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "name"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "tag",
      +        "type": "string"
      +      },
      +      "object": {
      +        "type": "string"
      +      },
      +      "object_path": {
      +        "type": "string"
      +      },
      +      "tag_name": {
      +        "type": "string"
      +      },
      +      "type_id": {
      +        "maximum": 9007199254740991,
      +        "minimum": -9007199254740991,
      +        "type": "integer"
      +      }
      +    },
      +    "required": [
      +      "kind"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "video_post",
      +        "type": "string"
      +      },
      +      "render_data": {
      +        "type": "string"
      +      },
      +      "type_id": {
      +        "maximum": 9007199254740991,
      +        "minimum": -9007199254740991,
      +        "type": "integer"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "render_data",
      +      "type_id"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "index": {
      +        "maximum": 9007199254740991,
      +        "minimum": 0,
      +        "type": "integer"
      +      },
      +      "kind": {
      +        "const": "shader",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "owner": {
      +        "allOf": [
      +          {
      +            "$ref": "#/definitions/__schema0"
      +          }
      +        ]
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "owner"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "id": {
      +        "type": "string"
      +      },
      +      "kind": {
      +        "const": "gv_node",
      +        "type": "string"
      +      },
      +      "name": {
      +        "type": "string"
      +      },
      +      "tag": {
      +        "allOf": [
      +          {
      +            "$ref": "#/definitions/__schema0"
      +          }
      +        ]
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "tag"
      +    ],
      +    "type": "object"
      +  },
      +  {
      +    "properties": {
      +      "kind": {
      +        "const": "plugin_options",
      +        "type": "string"
      +      },
      +      "plugin_id": {
      +        "anyOf": [
      +          {
      +            "maximum": 9007199254740991,
      +            "minimum": -9007199254740991,
      +            "type": "integer"
      +          },
      +          {
      +            "type": "string"
      +          }
      +        ]
      +      },
      +      "plugin_type": {
      +        "enum": [
      +          "command",
      +          "object",
      +          "tag",
      +          "material",
      +          "shader",
      +          "video_post",
      +          "scene_loader",
      +          "scene_saver",
      +          "bitmap_loader",
      +          "bitmap_saver",
      +          "tool",
      +          "preference",
      +          "node",
      +          "sculpt_brush"
      +        ],
      +        "type": "string"
      +      }
      +    },
      +    "required": [
      +      "kind",
      +      "plugin_id"
      +    ],
      +    "type": "object"
      +  }
      +]
  3. First observedv0.3.1

TDQS

A3.7/5.0
Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are present, so the description carries the full behavioral burden. It clearly states that the tool evaluates and returns transforms, but it does not disclose side effects such as playhead changes or restoration, safety profile, or read-only status, leaving the schema's restore_time parameter to cover some of that ground.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences with no filler: the first states the core operation and the second gives a focused use case. The structure is front-loaded and every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema and no annotations, the description must carry more return-value and behavioral context. It says transforms are returned, but not the shape of multi-frame results or side effects like playhead restoration, though the rich parameter schema covers inputs adequately.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so all six parameters are already well documented in the input schema. The description adds no parameter-level meaning beyond what the schema provides, such as format, space, fps, or handle resolution details.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: evaluate the scene at each requested frame and return the object's transform. The use case implicitly distinguishes it from raw keyframe or transform-setting tools, though no sibling MCP tool is named explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides clear context for when to use it: verifying alembic, constraint, or xpresso-driven animation without writing a custom exec_python sampler. It does not specify when-not to use it or name alternative sibling tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.