Old-vs-new text for one change

curl --request GET \
  --url https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff \
  --header 'Authorization: Bearer <token>'

import requests

url = "https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

{
  "data": {
    "changeId": 91,
    "changeKind": "amended",
    "beforeText": "An application for approval of a new drug...",
    "afterText": "An application for approval of a new drug or amended new drug...",
    "hasBefore": true,
    "hasAfter": true
  },
  "meta": {
    "processingTimeMs": 41,
    "creditsConsumed": 4
  }
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>",
      "input": "<unknown>",
      "ctx": {}
    }
  ]
}

{
  "detail": "Insufficient API credits."
}

Old-vs-new text for one change

The section’s text before and after this specific change, when available (see hasDiff on the change list above).

How many sides a change has depends on its kind, and each is a complete answer:

amended — both sides. This is the only kind where one side alone is not a partial answer but no answer.
added — after side only. There is no before side by definition, and the full text of a newly published section is precisely what the notification is for.
removed — before side only, the last text we held.

A missing side is not an error: hasBefore/hasAfter say which text is actually present, so a caller can render a graceful ‘diff unavailable’ state for older changes or a snapshot that failed to capture, instead of treating null as a failure.

Cost: 4 credits per call (see /api-credits/pricing). This is the only metered route in the alerts family: every other board and watch endpoint, including the /changes list this reads from, is free.

You are charged only for a diff that answers the question its kind asks, and creditsConsumed always reports what was actually billed. Refunded in full (creditsConsumed: 0): an amended change missing either side, an amended change whose two sides resolve to identical text (a capture artifact on our side, not a change on the publisher’s), and any change resolving no text at all. A one-sided added or removed diff is the complete answer and is charged normally.

GET

api

watches

{watch_id}

changes

{change_id}

diff

Old-vs-new text for one change

curl --request GET \
  --url https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff \
  --header 'Authorization: Bearer <token>'

import requests

url = "https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff"

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers)

print(response.text)

const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

fetch('https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.vaquill.ai/api/v1/watches/{watch_id}/changes/{change_id}/diff"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

{
  "data": {
    "changeId": 91,
    "changeKind": "amended",
    "beforeText": "An application for approval of a new drug...",
    "afterText": "An application for approval of a new drug or amended new drug...",
    "hasBefore": true,
    "hasAfter": true
  },
  "meta": {
    "processingTimeMs": 41,
    "creditsConsumed": 4
  }
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": "Insufficient API credits."
}

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>",
      "input": "<unknown>",
      "ctx": {}
    }
  ]
}

{
  "detail": "Insufficient API credits."
}

Authorizations

Authorization

string

header

required

API key issued from the developer dashboard. Pass as Authorization: Bearer vq_key_...

Path Parameters

watch_id

string

required

change_id

integer

required

Response

The change's before/after text (either side may be absent).

Last modified on September 7, 2026

US Statutes

Pricing

Board Watches

Old-vs-new text for one change

Authorizations

Path Parameters

Response