Aleteo

Ask for it like this

Copy this prompt, paste it into Claude or ChatGPT, and that's it. It's the short version: the minimum for the game to come out playable.

Make me a one-button game for the browser, in the style of the bird-and-pipes games, with original art.

- The character falls with gravity and rises a little with each tap.
- Pairs of obstacles come with a gap that changes height; 1 point for each pair I pass.
- I lose if I touch an obstacle, the ground or the ceiling.
- Difficulty goes up gradually: after 10 points the gap gets smaller and after 25 the obstacles move faster. Medals at 10, 25 and 50 points.
- At the start, the character hovers in place until my first tap, so I don't lose instantly.
- Screens: title, "tap to start", the game with a big score, and game over with score, high score and medal.
- Controls: space or click on desktop; tap the screen on mobile.
Technical: a single HTML file with the CSS and JavaScript inside, no libraries and no external images, everything drawn on canvas. It should fill the window and be playable with a finger on a phone and with keyboard or mouse on a computer.

Getting it as an HTML file

A game like this is a single file you open with a double click. These four steps are the same in any AI.

1. 1. Ask for the whole file

   Add this line at the end of your prompt: Give me a single, complete HTML file, nothing cut out, ready to save as index.html and open in the browser. Without it, you often get the code in pieces.

2. 2. Copy all of the code

   In Claude the game shows up on the side, already running, with a button to copy or download it. In ChatGPT, copy the whole code block: it has to start with <!DOCTYPE html> and end with </html>.

3. 3. Save it as index.html

   Paste it into Notepad (Windows) or TextEdit in plain text mode (Mac) and save it as index.html. Watch out for .txt: if the file ends up as index.html.txt, it won't open as a page.

4. 4. Double-click to open it

   It opens in your browser and it's ready to play, with nothing to install and no internet needed. To share it, upload it to any web host or send it by email: it's just one file.

If the game shows up blank, go back to the AI and paste the error from the browser console (right click → Inspect → Console). With that text it fixes it fast.

The full prompt, the one actually used

Longer and more specific: numbers, screens and style details. It's the one that produced exactly this game, unedited. Use it if you want to fine-tune the result.

Diego wrote it in Spanish and it stays in Spanish on purpose: it's the honest record of how the game was made, and a translation would be a prompt nobody used. Claude and ChatGPT understand it as is; add "Answer in English" if you want the game's text in English.

Hazme un juego de navegador llamado "Aleteo".

La idea: un colibrí que cae por gravedad y sube un poco cada vez que aletea, y tiene que pasar entre pares de cactus, al estilo de los juegos de un solo toque de pájaros y tubos, pero con arte original.

Mecánica:
- La gravedad jala al colibrí hacia abajo todo el tiempo. Cada aleteo le da un impulso fijo hacia arriba.
- Los pares de cactus, uno arriba y otro abajo, vienen desde la derecha con un hueco para pasar. El alto del hueco cambia en cada par.
- 1 punto por cada par que pasas.
- Pierdes si tocas un cactus, el suelo o el techo.
- La dificultad sube poco a poco: después de 10 puntos el hueco se achica un poco, y después de 25 los cactus se mueven un poco más rápido.
- Medallas de bronce, plata y oro a los 10, 25 y 50 puntos.
- Al empezar, el colibrí flota en el sitio hasta el primer aleteo, para que el jugador no pierda al instante.

Pantallas: título con Jugar; un "toca para empezar" con el colibrí flotando; el juego con el puntaje grande arriba; y fin con puntaje, récord, medalla y reintentar.

Controles: en PC, Espacio o clic para aletear. En celular, tocar en cualquier parte de la pantalla.

Estilo: desierto al atardecer con capas de cerros en parallax, colibrí verde tornasol con las alas que aletean rápido, cactus verdes con flores, y plumas que salen al chocar.

Técnico:
- Un solo archivo HTML con todo el CSS y el JavaScript dentro. Sin librerías, sin CDN, sin imágenes externas: todo dibujado en canvas.
- Tiene que llenar la ventana y adaptarse a cualquier tamaño, de celular a pantalla grande, sin deformarse.
- Tiene que jugarse completo desde celular (solo con el dedo) y desde PC (teclado o mouse).
- Tiene que funcionar dentro de un iframe con sandbox="allow-scripts". El récord va en localStorage dentro de try/catch para que el juego no se rompa si no hay acceso.
- Se pausa solo cuando la pestaña no está visible.
- El texto del juego va en español.

For ChatGPT, add the line from step 1 at the end: it tends to hand over the code in pieces.

What this prompt was missing

What became clear once the game was finished. If you're making your own from this one, add these from the start: fixing things later costs another round.

• Ask that the ground take up no more than a fifth of the screen when upright: here it took nearly a third.
• Say what should happen when you tie the high score, and whether the medal also shows during the run.

What was asked after the first result, in Diego's own words (Spanish):

• Agrégale un menú de pausa, un botón para cambiar entre español e inglés, y que el récord no se pierda al recargar.

It works in any AI

Claude, ChatGPT, Gemini, Copilot: the prompt is the same and so is the method. What changes is where you see the result. Four things that hold in all of them:

1. Ask for a single file

   "A single HTML file with everything inside, no libraries or CDN." That way the game works with a double click, with nothing to install, and you can upload it to any website.

2. Ask it to tell you what it assumed

   End with: "before writing the code, tell me in 5 lines what you assumed". That's where the gaps in your prompt show up, while fixing them is still cheap.

3. One fix per message

   Say what happens and what you expected. If you ask for three changes at once, one usually undoes another.

4. Ask it to test, not to promise

   "Check that every level can be won and tell me how you checked." That's how the games on this page found their bugs before going live.

The 6 parts of a good prompt, with a template to copy