API reference · CAIN Trajectory

Record Event To Trajectory

POST /fabric/trajectories/{trajectory_id}/events

Last reviewed 2026-11-06

POST /fabric/trajectories/{trajectory_id}/events

Submit a verified event to the trajectory and seal with Ed25519 node attestation.

Parameters

Name	In	Type	Meaning
`trajectory_id` required	path	string

Request body

RecordEventRequest (required)

Field	Type	Meaning
`action` required	string
`resource`	string or null
`tool`	string or null
`intent`	string or null
`decision`	string or null	default `"allow"`
`risk_score`	number or null	default `0.1`
`execution_status`	string or null	default `"executed"`

Responses

Status	Meaning	Body
`200`	Successful Response	object
`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 onlytrajectory_id pathRequest body application/json

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/trajectories/<trajectory_id>/events' \
  -H "X-API-Key: $CAIN_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"action": "action", "decision": "allow", "risk_score": 0.1, "execution_status": "executed"}'

import json, os, urllib.request

req = urllib.request.Request('https://cainstudio.online/fabric/trajectories/<trajectory_id>/events', method='POST',
    headers={"X-API-Key": os.environ["CAIN_API_KEY"], "Content-Type": "application/json"},
    data=json.dumps({
      "action": "action",
      "decision": "allow",
      "risk_score": 0.1,
      "execution_status": "executed"
    }).encode())
with urllib.request.urlopen(req, timeout=60) as r:
    print(r.status, json.load(r))

const res = await fetch("https://cainstudio.online/fabric/trajectories/<trajectory_id>/events", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.CAIN_API_KEY!,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "action": "action",
    "decision": "allow",
    "risk_score": 0.1,
    "execution_status": "executed"
  }),
});
console.log(res.status, await res.json());

Schemas used

Error · HTTPValidationError · RecordEventRequest · ValidationError

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