Detect Key

Tool name: detect-key

Ranks the top 5 candidate keys for a chord progression or note set. Provide exactly one of chords or notes.

Annotations

Hint	Value
readOnlyHint	✓
idempotentHint	✓
destructiveHint	—
openWorldHint	—

Input

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "chords": {
      "minItems": 1,
      "type": "array",
      "items": {
        "type": "string",
        "minLength": 1
      }
    },
    "notes": {
      "minItems": 1,
      "type": "array",
      "items": {
        "type": "string",
        "minLength": 1
      }
    }
  },
  "additionalProperties": false
}

Output

Returned as structuredContent. The text rendering is a short human-readable summary.

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "candidates": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "key": {
            "type": "string",
            "description": "Key name, e.g. \"C major\" or \"A minor\"."
          },
          "score": {
            "type": "number",
            "description": "Higher score = better fit. Normalized by input length."
          }
        },
        "required": [
          "key",
          "score"
        ],
        "additionalProperties": false
      },
      "description": "Top 5 ranked key candidates."
    }
  },
  "required": [
    "candidates"
  ],
  "additionalProperties": false
}