mtg-oracle

Instructions

Implementation Reference

• src/tools/get-rulings.ts:32-64 (handler)

  The implementation of the get_rulings tool handler, which queries the database for cards and their associated rulings.

  export function handler(db: Database.Database, params: GetRulingsParams): GetRulingsResult {
    // Look up card by name (case-insensitive exact match first, then LIKE)
    let card = db.prepare(
      'SELECT * FROM cards WHERE LOWER(name) = LOWER(?)'
    ).get(params.card_name) as CardRow | undefined;
  
    if (!card) {
      card = db.prepare(
        'SELECT * FROM cards WHERE LOWER(name) LIKE LOWER(?)'
      ).get(`%${params.card_name}%`) as CardRow | undefined;
    }
  
    if (!card) {
      return {
        found: false,
        message: `No card found matching "${params.card_name}"`,
      };
    }
  
    const rows = db.prepare(
      'SELECT * FROM rulings WHERE card_id = ? ORDER BY published_at'
    ).all(card.id) as RulingRow[];
  
    return {
      found: true,
      card_name: card.name,
      rulings: rows.map(r => ({
        source: r.source,
        published_at: r.published_at,
        comment: r.comment,
      })),
    };
  }

• src/tools/get-rulings.ts:7-9 (schema)

  Input schema for the get_rulings tool.

  export const GetRulingsInput = z.object({
    card_name: z.string().describe('Name of the card to get rulings for'),
  });

• src/server.ts:118-126 (registration)

  Registration of the get_rulings tool in the MCP server.

  server.tool(
    'get_rulings',
    'Get official rulings for a specific Magic card. Use this when a user asks about specific interactions, edge cases, or how a card works in unusual situations. Returns timestamped rulings from Wizards of the Coast.',
    GetRulingsInput.shape,
    async (params) => {
      try {
        const result = getRulingsHandler(db, params);
        return { content: [{ type: 'text' as const, text: formatGetRulings(result) }] };
      } catch (err) {