API reference · Trust Fabric

Replay recorded decisions under proposed settings

GET /fabric/simulate

Last reviewed 2026-11-06

GET /fabric/simulate

Answers "if I turn this on, what breaks?" against your own traffic.

Read-only and side-effect free. It recomputes recorded outcomes rather than re-running the decision path, so it cannot alter how live traffic is decided and cannot create evidence, queue entries or billable usage.

Parameters

Name	In	Type	Meaning
`enforce`	query	boolean	default `true`
`approval_enforce`	query	boolean or null
`verify_enforce`	query	boolean or null
`limit`	query	integer	default `200`

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 onlyenforce queryapproval_enforce queryverify_enforce querylimit query

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 GET 'https://cainstudio.online/fabric/simulate' \
  -H "X-API-Key: $CAIN_API_KEY"

import json, os, urllib.request

req = urllib.request.Request('https://cainstudio.online/fabric/simulate', method='GET',
    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/simulate", {
  method: "GET",
  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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