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MCP ToolsArtist & Critique

compare_sketches

Side-by-side capture of 2-4 sketches with comparison framework.

Input Schema

ParameterTypeRequiredDescription
sketchIdsarray of stringYesIDs of the sketches to compare. Must contain 2 to 4 entries.
aspectsarray of "composition" | "color" | "rhythm" | "unity" | "expression"NoWhich aspects to compare across sketches. Defaults to all five.
previewSizenumberNoSize in pixels for each captured screenshot. Default: 300.

Output Shape

{
  "screenshots": {
    "<sketchId>": "<base64 image>"
  },
  "comparison": {
    "aspects": [
      {
        "name": "composition",
        "perSketch": {
          "<sketchId>": "..."
        },
        "synthesis": "..."
      }
    ]
  }
}

Side Effects

  • Captures a screenshot of each sketch at the requested preview size.

Error Cases

ErrorCause
Sketch not foundOne or more of the provided sketchIds do not match any saved sketch.
Too few sketchesFewer than 2 sketch IDs were provided.
Too many sketchesMore than 4 sketch IDs were provided.
Invalid aspectAn unrecognized aspect string was included in the aspects array.

Golden Path Example

Request

{
  "sketchIds": ["sketch-a", "sketch-b"],
  "aspects": ["color", "rhythm"],
  "previewSize": 300
}

Response

{
  "screenshots": {
    "sketch-a": "<base64 image>",
    "sketch-b": "<base64 image>"
  },
  "comparison": {
    "aspects": [
      {
        "name": "color",
        "perSketch": {
          "sketch-a": "Muted earth tones with high value contrast.",
          "sketch-b": "Saturated primaries with low value contrast."
        },
        "synthesis": "sketch-a achieves depth through value while sketch-b relies on hue separation."
      },
      {
        "name": "rhythm",
        "perSketch": {
          "sketch-a": "Regular, grid-based repetition.",
          "sketch-b": "Organic, irregular spacing."
        },
        "synthesis": "The regularity in sketch-a feels mechanical; sketch-b has more visual energy but risks chaos."
      }
    ]
  }
}