API reference · Trust Fabric
Register a principal
POST /fabric/identity/principals
Last reviewed 2026-10-02
POST /fabric/identity/principals
Request body
PrincipalCreate (required)
| Field | Type | Meaning |
|---|---|---|
kind required | string | agent | human | service |
display_name required | string | min length 1 · max length 200 |
public_key | string or null | base64 Ed25519 public key (32 bytes) |
metadata | object |
Responses
| Status | Meaning | Body |
|---|---|---|
201 | Successful Response | JSON |
422 | Validation Error | HTTPValidationError |
401 | No key, or a key that is not valid | JSON detail |
429 | Rate limit for your plan reached; retry after the Retry-After seconds | JSON detail |
Try it
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/identity/principals' \
-H "X-API-Key: $CAIN_API_KEY" \
-H 'Content-Type: application/json' \
-d '{"kind": "kind", "display_name": "display-name"}'import json, os, urllib.request
req = urllib.request.Request('https://cainstudio.online/fabric/identity/principals', method='POST',
headers={"X-API-Key": os.environ["CAIN_API_KEY"], "Content-Type": "application/json"},
data=json.dumps({
"kind": "kind",
"display_name": "display-name"
}).encode())
with urllib.request.urlopen(req, timeout=60) as r:
print(r.status, json.load(r))const res = await fetch("https://cainstudio.online/fabric/identity/principals", {
method: "POST",
headers: {
"X-API-Key": process.env.CAIN_API_KEY!,
"Content-Type": "application/json",
},
body: JSON.stringify({
"kind": "kind",
"display_name": "display-name"
}),
});
console.log(res.status, await res.json());Schemas used
HTTPValidationError · PrincipalCreate · ValidationError
← List this tenant's principals · all 79 Trust Fabric calls · Fetch one principal →
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