Developer limits

Limit	Current bound
App canvas	64×32 pixels
Top-level Starlark files	Exactly one
Source encoding	Non-empty UTF-8, no NUL bytes
Source size	128 KiB maximum
Review preview	Non-empty WebP, 2 MiB maximum
Local validation render	1 second target bound
Local push render timeout	30 seconds
Developer projects	5 per account during preview
Saved developer source	50 MiB per account during preview
Active submission	One queued or in-review submission per project

MCP inputs add field-specific bounds, UUID validation, configuration-schema checks, rate limits, and explicit confirmation for destructive operations.

Limits can become stricter before public launch. Treat a passing browser preview as development feedback, not proof that hosted or physical-device gates pass.

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Developer limits