Only granted tools
- stripe.refundGranted
- NetworkBlocked
- File systemBlocked
Default: nothing
Safely run the code your agents write
Your permissions enforced on each call, with an audit trail.
Why Submilli
Every program gets its own sandbox
Each program runs in its own WebAssembly sandbox, with no network or file system access by default, and no startup time.
Sandboxes share one server process.
See how a program runsPermissions down to each argument
A tool allowlist only says which tools. A Blueprint goes down to each argument, and the runtime enforces it outside the model.
Stored credentials stay hidden from the model. Your agent's code can use them.
Watch how Blueprints workEvery call checked
Your permissions, enforced
- Read details✓ Allowed
- Send message? Ask a human
- Delete record× Denied
Runs that pick up where they stopped
A run continues after a server crash or restart. Finished steps are not repeated, with no separate workflow engine or workflow code.
An interrupted step can run again, so external effects must be safe to repeat. A stuck run needs an explicit resume.
See how runs recoverFinished steps never re-run
Run progress2 kept · 1 resumed
Server restart
- Read details
- kept
- Prepare message
- kept
- Send message
- resumed
Built for agents that write code
The agent writes one program instead of calling tools one at a time. The model sees the result.
Submilli helps it find Packages and fix errors in that code.
Learn why code execution works>98% fewer tokens
Before150,000 tokens
With code execution2,000 tokens