Observed arrival · 2026-10-09
Shotcup’s disposable JavaScript sandboxes
Shotcup offers deterministic, short-lived JavaScript sandboxes for AI agents, with runs available through REST and MCP.
○Open
⊠Login
$Paid
†Ads
✦Pretty
●Pro
◎Niche
◉Human
⚑Risk
ƒJS
- For
- Developers building tools and workflows for AI agents
- Worth noticing
- Its performance page dates measurements and explains methods, while also disclosing that raw compute is slower than V8.
Field notes
The homepage lays out a run as a sequence: an agent plans, writes main.js, executes it in a fresh sandbox, and can inspect errors and retry. It describes tool calls from code, approval pauses, seeded clocks and randomness, and artifacts returned from /out. Performance figures are dated October 8, 2026; the page also reports a separate 2.1 ms p50 nested-sandbox measurement from the engine on an M1 Max.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
$PaidCommerce or pricing visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
ƒJavaScriptBrowser-side code central
One card from the complete issue