API reference · Trust Fabric

See CAIN decide on a real action -- no account needed

POST /fabric/try

Last reviewed 2026-11-06

POST /fabric/try

The five-minute path: watch the fabric intercept an action, decide, enforce.

Unauthenticated on purpose. An engineer evaluating a trust platform should not have to hand over an email address to find out whether it does anything.

Safety properties, because this is a public endpoint that executes the real decision path: * scenarios are FIXED, so this is not an oracle for probing our screens * it runs against a throwaway tenant, never a customer's * rate limited per IP * the enforcement mode is forced on for the demo, so a visitor sees the control actually blocking rather than shadow-mode observing

Parameters

Name	In	Type	Meaning
`scenario`	query	string	default `"safe-read"`

Responses

Status	Meaning	Body
`200`	Successful Response	JSON
`401`	The X-API-Key header is missing, or the key is unknown, revoked or replaced.	`Error`
`403`	The key is valid but may not do this (for example an agent key approving its own held action).	`Error`
`422`	Validation Error	`HTTPValidationError`
`429`	Rate limit or monthly quota reached. Wait for the number of seconds in Retry-After when it is sent.	`Error`

Try it

Your API key X-API-Key Remember the key in this tab onlyscenario query

This call changes data in the account the key belongs to.

The request goes from your browser straight to this site. Your key is not stored unless you tick the box, and then only in this tab's session storage.

Code

curl -sS -X POST 'https://cainstudio.online/fabric/try' \
  -H "X-API-Key: $CAIN_API_KEY"

import json, os, urllib.request

req = urllib.request.Request('https://cainstudio.online/fabric/try', method='POST',
    headers={"X-API-Key": os.environ["CAIN_API_KEY"]})
with urllib.request.urlopen(req, timeout=60) as r:
    print(r.status, json.load(r))

const res = await fetch("https://cainstudio.online/fabric/try", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.CAIN_API_KEY!,
  },
});
console.log(res.status, await res.json());

Schemas used

Error · HTTPValidationError · ValidationError

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