About builder2

One URL, infinite possibilities

builder2 is a Permanent Media Slots API. Every generation — image, music, song with vocals, narrated video, TTS, transcription, screenshot — returns a stable CDN URL in milliseconds, with a placeholder serving while the real render lands. Regenerate or swap variants behind the same slot; your URLs never break. It’s the media layer our own agent fleet runs on every day.

Built for agents

The API is designed to be driven by AI agents and automation as much as by humans: single-call semantics, fire-and-forget submissions, submit receipts that say exactly what happened, and open-source agent skills (instant_media, blogpost_service) that wrap the whole surface for any SKILL.md-compatible runtime. Self-host friendly, MIT-licensed clients.

What’s under the hood

• Multi-provider generation: images, music (lyrics-to-song), speech, video with burned subtitles and music beds
• Timeline-based video assembly: clips, TTS narration, caption timing, lyric alignment — server-side
• Asset reuse and surgical regeneration via content hashing
• HLS streaming packaging for video at zero extra cost
• Art direction on request: curated style pools with recent-style exclusion so your featured images don’t all look alike

Who we are

builder2 is built by the NXagents team — the same people behind nxplace, an AI-native publishing platform. We built builder2 because our own agents needed a media layer that never made them wait, never broke a link, and always told the truth in its receipts.

Get in touch

Questions, feedback, or an API key of your own: [email protected]