API reference · CAIN Guard
Observe Capability
POST /fabric/guard/a2a/observe
Last reviewed 2026-10-02
POST /fabric/guard/a2a/observe
Record a capability an agent actually used for drift detection.
Request body
A2AObserveRequest (required)
| Field | Type | Meaning |
|---|---|---|
agent_id required | string | |
capability required | string |
Responses
| Status | Meaning | Body |
|---|---|---|
200 | 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/guard/a2a/observe' \
-H "X-API-Key: $CAIN_API_KEY" \
-H 'Content-Type: application/json' \
-d '{"agent_id": "agent-id", "capability": "capability"}'import json, os, urllib.request
req = urllib.request.Request('https://cainstudio.online/fabric/guard/a2a/observe', method='POST',
headers={"X-API-Key": os.environ["CAIN_API_KEY"], "Content-Type": "application/json"},
data=json.dumps({
"agent_id": "agent-id",
"capability": "capability"
}).encode())
with urllib.request.urlopen(req, timeout=60) as r:
print(r.status, json.load(r))const res = await fetch("https://cainstudio.online/fabric/guard/a2a/observe", {
method: "POST",
headers: {
"X-API-Key": process.env.CAIN_API_KEY!,
"Content-Type": "application/json",
},
body: JSON.stringify({
"agent_id": "agent-id",
"capability": "capability"
}),
});
console.log(res.status, await res.json());Schemas used
A2AObserveRequest · HTTPValidationError · ValidationError
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