# Indie game development tools to make your game and grow it > Build with an AI agent in a real engine, generate the assets a small team never has time for, and make the store art and marketing that decide whether anyone finds the game. Even if you build it in another engine. - URL: https://www.summerengine.com/for/indie-devs - Keyword: indie game development tools **The short answer:** Summer is a free desktop game engine plus a paid set of AI tools for the rest of the job, covering 3D models, sprites, voice, sound effects, music, key art and video. Build the game in Summer with its agent or with Claude Code, Cursor or Codex, or keep your current engine and use Summer only for assets and marketing. Either way, the same account and the same asset library follow you across projects. Indie teams are one to five people doing the work of twenty across design, code, art, audio, trailers, store pages and social posts. Most AI tools help with one of those. You end up with five subscriptions and a folder of files that still need to get into the game, resized, re-exported and wired up by hand before anyone can even tell if the idea works. Summer is built around the whole path. The engine and its agent build and test the game. Studio generates the assets and drops them into the project. The same tools make the capsule art and marketing clips that go on Steam and social. The point is not that any one generator is the best in its category; it is that build, asset and marketing all read from the same project, so nothing gets lost between tools. You do not have to switch engines to benefit. Every asset comes out as a standard file (GLB models, image files, WAV and MP3 audio, MP4 video) that works in Unity, Godot, Unreal or GameMaker. A one-person team can use Summer purely as an asset and marketing pipeline around a game built somewhere else, and add the engine and agent side later if it earns a place in the workflow. ## What it does - **Build in a real engine with an agent:** Describe features and the agent edits scenes and scripts, runs the game and fixes what breaks. Works with the built-in agent or Claude Code, Cursor and Codex through the Summer MCP. - **3D, 2D and audio assets:** Generate rigged 3D characters, sprites and sprite sheets, NPC voices, sound effects and music, then place them in the scene. - **Steam capsule art for the store:** Make key art from your own characters and export every Steam capsule and library size with the right rules. - **Grow with clips for social:** Generate short video shots with Seedance 2.0, Veo 3.1 or Kling 3.0 in vertical or wide formats for posts and ads, and cut them alongside your own captured gameplay. ## How it works 1. **Download Summer:** The engine is free for macOS (Apple silicon) and Windows. Start from a template or open a compatible project. 2. **Build with the agent:** Use the built-in agent, or connect Claude Code, Cursor or Codex with one setup command. 3. **Fill the gaps with Studio:** Generate the assets you are missing and let the agent import and wire them. 4. **Ship and market:** Export your build, make capsule art and social clips, and publish where you want. You own the game. ## In Studio, or from the agent you already use ### In Summer Studio Studio on the web holds every generator in one place (Image, 3D, Audio, Video and Animation), with your asset library shared with the desktop engine. [Open Summer Studio](https://www.summerengine.com/studio) ### From Claude, Cursor or Codex via MCP If you already code with an AI agent, install the Summer MCP and keep your workflow. The agent gets engine control plus the generators. Example prompt for your agent: ```text Read the Summer project context and list the three biggest gaps before this game is demo ready. Then replace the placeholder art and sound in the first level and run a playtest. ``` [Set up the Summer MCP](https://www.summerengine.com/mcp) ## What it costs - 3D model, Hunyuan 3D v3.1 Pro: $0.53 - Image, Nano Banana 2 Lite (1K): $0.04 (estimate) - Sound effect, 5 seconds: $0.01 - Music, per minute of track: $0.15 - Video clip, Seedance 2.0, 8 seconds: $2.42 (estimate) Prices are charged from your Summer usage balance. Generating assets needs a paid plan or a top-up: Pro is $20 a month and includes $20 of usage, and top-ups start at $5. The desktop engine itself is free to download. ## Prompts that work, and what comes back What a week of indie work looks like with Summer in the loop. ### Monday, vertical slice - Prompt: Build a first playable room: third-person character, one enemy type, a door that opens with a key. - What you get: A playable scene the agent has already run and checked. ### Tuesday, art pass - Prompt: Replace the grey boxes with stylized low poly props and a rigged enemy with walk and attack animations. - What you get: Generated 3D assets placed in the level. ### Wednesday, audio - Prompt: Add footsteps, hit sounds, an exploration track and voice lines for the gatekeeper. - What you get: Sound effects, music and dialogue imported and triggered. ### Thursday, store page - Prompt: Make key art of our hero on the cliff and export all Steam capsule sizes. - What you get: A full capsule set ready for Steamworks. ### Friday, announce - Prompt: Generate three 8-second vertical shots of the world for a teaser post. - What you get: Clips to cut together with real gameplay footage. [Browse game templates](https://www.summerengine.com/templates) ## Built in another engine? Use Summer for the rest Plenty of indie developers are years into a Unity, Godot or Unreal project. Summer does not ask you to move. The asset generators, capsule workflow and video tools work on their own and export standard files. If you ever want to move a project, Summer has porting guides for common engines. In practice this means a Unity developer can open Studio in a browser, generate a rigged 3D character, download the GLB and import it the same way they would a Blender export. The AI tooling does not know or care which engine eventually loads the file. ## What is not there yet Summer cannot yet record gameplay to a video file for trailers; the video tools generate new shots rather than capturing your game. Trailers today combine your own screen recordings with generated shots. Asset generation needs a paid plan or a top-up; the engine does not. Be direct about that split when you plan a launch. Budget for a screen recorder and a rough edit for the real gameplay beats in a trailer, and let generated shots carry the moments a camera cannot easily capture, like a sweeping establishing shot of a world that only exists as level geometry so far. ## Frequently asked questions ### Is Summer free for indie developers? The desktop engine is free to download and use. The AI generators and hosted AI are paid, through a plan or a top-up. ### Do I have to make my game in Summer? No. You can use Studio for assets, capsule art and video with any engine. The files are standard formats. ### Do I keep the rights to my game? Yes. You own your game and can launch it wherever you want. Summer's terms state that you retain ownership of the content you create. ### Can I publish on Steam? Yes. Export your build and publish through Steamworks. Disclose AI-generated content in Steam's content survey. ### Which AI agents does Summer work with? The built-in agent in the desktop app, plus Claude Code, Cursor, Codex, Gemini CLI, Cline and many other agents through the Summer MCP. ### How is this different from just using separate AI tools for art, audio and video? Those tools each do one job well but do not know your project. In Summer, generated assets land in the same library the engine reads from, so the agent can place a model, wire a sound to an event or reuse a character reference for key art without you re-uploading files between apps. ## Related tools and guides - [AI game maker for indie devs](https://www.summerengine.com/ai-game-maker-for-indie-devs) - [Guide to AI tools for indie game developers](https://www.summerengine.com/blog/ai-tools-for-indie-game-developers) - [AI 3D model generator for games](https://www.summerengine.com/ai-3d-model-generator-for-games) - [Steam capsule art generator](https://www.summerengine.com/steam-capsule-art-generator) - [Claude Code game development](https://www.summerengine.com/claude-code-game-development) - [Porting a game you own](https://www.summerengine.com/porting) - [Summer for game marketers](https://www.summerengine.com/for/marketers) - [Pricing](https://www.summerengine.com/pricing) [Download Summer free](https://www.summerengine.com/download) --- ## Machine-readable resources - Site index for agents: https://www.summerengine.com/llms.txt - Full inlined content: https://www.summerengine.com/llms-full.txt - Porting catalog: https://www.summerengine.com/llms-porting.txt - Structured catalog: https://www.summerengine.com/agent-catalog.json - Sitemap: https://www.summerengine.com/sitemap.xml - Developer resources: https://www.summerengine.com/docs - Summer API (assets from any agent or code; public per-call model prices): https://docs.summerengine.com/api