bs_human_fire

Instructions

Implementation Reference

• src/games/battleship.ts:241-262 (handler)

  The handler for the bs_human_fire tool. Validates game state (in_progress, pirate's turn, not already fired at coordinates), calls fireShot(), checks for victory via allSunk(), and updates the game state.

    async ({ row, col }) => {
      if (bsGame.status !== "in_progress") {
        return { content: [{ type: "text", text: `The battle is over (${bsGame.status}). Call bs_new_game to sail again.` }], isError: true };
      }
      if (bsGame.currentTurn !== "pirate") {
        return { content: [{ type: "text", text: `The Navy hasn't fired yet this round. Call bs_claude_fire first.` }], isError: true };
      }
      if (bsGame.pirateAttacks[row][col] !== "?") {
        return { content: [{ type: "text", text: `You already fired at (row ${row}, col ${col}). Pick different waters.\n\n${renderState(bsGame)}` }], isError: true };
      }
  
      const { summary } = fireShot(bsGame.pirateAttacks, bsGame.navyGrid, bsGame.navyShips, row, col);
  
      if (allSunk(bsGame.navyShips)) {
        bsGame.status = "pirates_win";
        return { content: [{ type: "text", text: `${summary}\n\n${renderState(bsGame)}` }] };
      }
  
      bsGame.currentTurn = "navy";
      return { content: [{ type: "text", text: `${summary}\n\nThe Navy is lining up their cannons — call bs_claude_fire to return fire.\n\n${renderState(bsGame)}` }] };
    }
  );

• src/games/battleship.ts:237-240 (schema)

  Input schema for bs_human_fire: row and col are integers 0-9.

  {
    row: z.number().int().min(0).max(9).describe("Row index: 0 = top, 9 = bottom"),
    col: z.number().int().min(0).max(9).describe("Column index: 0 = left, 9 = right"),
  },

• src/games/battleship.ts:234-262 (registration)

  Registration of the bs_human_fire tool on the MCP server via server.tool(), within the registerBattleshipTools function.

  server.tool(
    "bs_human_fire",
    "Fire the pirate cannons at the given coordinates on the Navy's grid. Call this when the human gives their shot. Returns hit/miss/sunk — and if sunk, reveals what that Navy ship was carrying.",
    {
      row: z.number().int().min(0).max(9).describe("Row index: 0 = top, 9 = bottom"),
      col: z.number().int().min(0).max(9).describe("Column index: 0 = left, 9 = right"),
    },
    async ({ row, col }) => {
      if (bsGame.status !== "in_progress") {
        return { content: [{ type: "text", text: `The battle is over (${bsGame.status}). Call bs_new_game to sail again.` }], isError: true };
      }
      if (bsGame.currentTurn !== "pirate") {
        return { content: [{ type: "text", text: `The Navy hasn't fired yet this round. Call bs_claude_fire first.` }], isError: true };
      }
      if (bsGame.pirateAttacks[row][col] !== "?") {
        return { content: [{ type: "text", text: `You already fired at (row ${row}, col ${col}). Pick different waters.\n\n${renderState(bsGame)}` }], isError: true };
      }
  
      const { summary } = fireShot(bsGame.pirateAttacks, bsGame.navyGrid, bsGame.navyShips, row, col);
  
      if (allSunk(bsGame.navyShips)) {
        bsGame.status = "pirates_win";
        return { content: [{ type: "text", text: `${summary}\n\n${renderState(bsGame)}` }] };
      }
  
      bsGame.currentTurn = "navy";
      return { content: [{ type: "text", text: `${summary}\n\nThe Navy is lining up their cannons — call bs_claude_fire to return fire.\n\n${renderState(bsGame)}` }] };
    }
  );

• src/games/battleship.ts:111-138 (helper)

  The fireShot() helper function called by the bs_human_fire handler. Checks if the shot hits a ship, marks hits, and returns the result (miss/hit/sunk) with a summary string.

  function fireShot(
    attackGrid: AttackCell[][],
    targetGrid: boolean[][],
    targetShips: ShipState[],
    row: number,
    col: number
  ): { result: "miss" | "hit" | "sunk"; ship?: ShipState; summary: string } {
    if (!targetGrid[row][col]) {
      attackGrid[row][col] = "O";
      return { result: "miss", summary: `Cannonball splashes into the water at (row ${row}, col ${col}). Miss!` };
    }
  
    const ship = targetShips.find(s => s.positions.some(([r, c]) => r === row && c === col))!;
    ship.hitCount++;
    attackGrid[row][col] = "X";
  
    if (ship.hitCount === ship.size) {
      ship.sunk = true;
      for (const [r, c] of ship.positions) attackGrid[r][c] = ship.letter;
      return {
        result: "sunk",
        ship,
        summary: `DIRECT HIT at (row ${row}, col ${col})! **${ship.name}** has been sent to the bottom!\n💀 Recovered from the wreck: *${ship.cargo}*`,
      };
    }
  
    return { result: "hit", summary: `Hit! (row ${row}, col ${col}) — ${ship.name} is taking on water!` };
  }