API reference · CAIN AGI Control Boundary

Agi Submit Proposal

POST /fabric/agi/propose

Last reviewed 2026-11-06

POST /fabric/agi/propose

Runs a proposal through the real, full ControlBoundary pipeline, including the last-mile enforcement stage. `agent_id` must already be a registered ACTIVE identity in this tenant (see the CAIN Identity API) holding capability `tool:{action_verb}` -- this endpoint grants no authority of its own, it only evaluates what identity_engine already says the caller has.

Request body

SubmitProposalRequest (required)

Field	Type	Meaning
`agent_id` required	string	min length `1`
`action_verb` required	string	min length `1` · max length `255`
`target_resource` required	string	min length `1` · max length `2048`
`arguments`	object
`intent` required	string	min length `1` · max length `4096`
`confidence`	number	default `1.0`
`memory_refs`	array of string
`claims`	object
`plan_id`	string	default `""`
`step_index`	integer	default `0`
`signature_b64`	string or null
`public_key_b64`	string or null
`session_id`	string or null
`proposal_id`	string or null	pattern `^urn:cain:agi-proposal:[0-9a-f]{24,64}$`

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 onlyRequest 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/agi/propose' \
  -H "X-API-Key: $CAIN_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"agent_id": "agent-id", "action_verb": "action-verb", "target_resource": "target-resource", "intent": "intent", "confidence": 1.0, "plan_id": "", "step_index": 0}'

import json, os, urllib.request

req = urllib.request.Request('https://cainstudio.online/fabric/agi/propose', method='POST',
    headers={"X-API-Key": os.environ["CAIN_API_KEY"], "Content-Type": "application/json"},
    data=json.dumps({
      "agent_id": "agent-id",
      "action_verb": "action-verb",
      "target_resource": "target-resource",
      "intent": "intent",
      "confidence": 1.0,
      "plan_id": "",
      "step_index": 0
    }).encode())
with urllib.request.urlopen(req, timeout=60) as r:
    print(r.status, json.load(r))

const res = await fetch("https://cainstudio.online/fabric/agi/propose", {
  method: "POST",
  headers: {
    "X-API-Key": process.env.CAIN_API_KEY!,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "agent_id": "agent-id",
    "action_verb": "action-verb",
    "target_resource": "target-resource",
    "intent": "intent",
    "confidence": 1.0,
    "plan_id": "",
    "step_index": 0
  }),
});
console.log(res.status, await res.json());

Schemas used

Error · HTTPValidationError · SubmitProposalRequest · ValidationError

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