CAIN-42 CAIN Studio

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)

FieldTypeMeaning
agent_id requiredstring
capability requiredstring

Responses

StatusMeaningBody
200Successful ResponseJSON
422Validation ErrorHTTPValidationError
401No key, or a key that is not validJSON detail
429Rate limit for your plan reached; retry after the Retry-After secondsJSON 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"}'

Schemas used

A2AObserveRequest · HTTPValidationError · ValidationError

← Check Nonce · all 10 CAIN Guard calls · Register A2A Card →

Try CAIN-42 on your own agents

Create a free account and every new account starts with a 7-day trial of the full platform. Or try the sandbox first, with no account at all.

Create a free account →  ·  Try the sandbox  ·  See the whole ecosystem