Pro
£29
Test subscription. No real charge is made.
ONCE PLAYGROUND / 001
ACTIVATE A HOSTED
SANDBOX.
Optional hosted activation uses Stripe test checkout. This is separate from learning the retry decisions. Run the ungated simulation first. Do not enter real card data.
EXECUTION SAFETY / LIVE MODEL
READY
ATTEMPT 01
EXECUTE
NETWORK
AMBIGUOUS
ATTEMPT 02
RETRY
EXPECTED EFFECTS
01
01 · FAILURE MODEL
The provider succeeds.
The provider succeeds.
The response disappears.
A timeout cannot prove that the external action failed. Retrying blindly can perform the same irreversible operation twice.
01
AGENT
Send consequential action
02
PROVIDER
Side effect committed
03
NETWORK
Response lost
04
RETRY
Duplicate exposure
02 · START SANDBOX
Choose the environment.
Choose the environment.
Then prove it.
Stripe is running in test mode. These plans exercise the real activation path without charging real money.
Startup
£79
Test subscription. No real charge is made.
Scale
£199
Test subscription. No real charge is made.
03 · EXPECTED PROOF
Two attempts.
Two attempts.
One external effect.
After activation, the live demo deliberately creates the ambiguous retry path and checks provider truth afterwards.
ATTEMPTS
02
Same operation identity
LEDGER
CONFIRMED
Durable state resolved
SIDE EFFECTS
01
Provider truth
DECISION
SAFE
Duplicate suppressed