Refine Prompt

POST /v2/agents/prompt/refine

Refine Prompt

cURL

curl --request POST \
  --url https://api.velt.dev/v2/agents/prompt/refine \
  --header 'Content-Type: application/json' \
  --header 'x-velt-api-key: <x-velt-api-key>' \
  --header 'x-velt-auth-token: <x-velt-auth-token>' \
  --data '
{
  "data": {
    "analysisPrompt": "<string>",
    "demoFeedback": [
      {}
    ],
    "provider": "<string>"
  }
}
'

import requests

url = "https://api.velt.dev/v2/agents/prompt/refine"

payload = { "data": {
        "analysisPrompt": "<string>",
        "demoFeedback": [{}],
        "provider": "<string>"
    } }
headers = {
    "x-velt-api-key": "<x-velt-api-key>",
    "x-velt-auth-token": "<x-velt-auth-token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'x-velt-api-key': '<x-velt-api-key>',
    'x-velt-auth-token': '<x-velt-auth-token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({data: {analysisPrompt: '<string>', demoFeedback: [{}], provider: '<string>'}})
};

fetch('https://api.velt.dev/v2/agents/prompt/refine', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.velt.dev/v2/agents/prompt/refine",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'data' => [
        'analysisPrompt' => '<string>',
        'demoFeedback' => [
                [
                                
                ]
        ],
        'provider' => '<string>'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-velt-api-key: <x-velt-api-key>",
    "x-velt-auth-token: <x-velt-auth-token>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

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

func main() {

	url := "https://api.velt.dev/v2/agents/prompt/refine"

	payload := strings.NewReader("{\n  \"data\": {\n    \"analysisPrompt\": \"<string>\",\n    \"demoFeedback\": [\n      {}\n    ],\n    \"provider\": \"<string>\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-velt-api-key", "<x-velt-api-key>")
	req.Header.Add("x-velt-auth-token", "<x-velt-auth-token>")
	req.Header.Add("Content-Type", "application/json")

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.velt.dev/v2/agents/prompt/refine")
  .header("x-velt-api-key", "<x-velt-api-key>")
  .header("x-velt-auth-token", "<x-velt-auth-token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"data\": {\n    \"analysisPrompt\": \"<string>\",\n    \"demoFeedback\": [\n      {}\n    ],\n    \"provider\": \"<string>\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.velt.dev/v2/agents/prompt/refine")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["x-velt-api-key"] = '<x-velt-api-key>'
request["x-velt-auth-token"] = '<x-velt-auth-token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"data\": {\n    \"analysisPrompt\": \"<string>\",\n    \"demoFeedback\": [\n      {}\n    ],\n    \"provider\": \"<string>\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "result": {
    "status": "success",
    "message": "Prompt refined successfully",
    "data": {
      "refinerResult": {
        "analysis_prompt": "## Objective\n...\n\n## Detection Logic\n...",
        "response_descriptions": {}
      }
    }
  }
}

Use this API to refine an existing analysis prompt based on feedback from demo runs. You provide the current prompt and a list of demos with the user’s feedback on what went wrong; the engine returns a refined analysis prompt and updated response descriptions.

This is the iteration step in the prompt-design loop: run Validate Prompt to expand a simple instruction, run the demos against the resulting prompt, then refine when the demos don’t pass.

Endpoint

POST https://api.velt.dev/v2/agents/prompt/refine

Headers

x-velt-api-key · string · required

Your API key.

x-velt-auth-token · string · required

Your Auth Token.

Body

Params

data · object · required

Show properties

analysisPrompt · string · required

Min 1 char. The current analysis prompt to refine. Typically the analysis_prompt returned by Validate Prompt.

demoFeedback · object[] · required

Min 1 entry. Demo feedback items.

Each entry:

Field	Type	Required	Description
demoId	string	yes	Min 1 char. Stable demo identifier.
demoTitle	string	yes	Min 1 char. Human-readable demo title.
demoHtml	string	yes	Min 1 char. HTML content the demo was run against.
demoExpected	string	yes	Min 1 char. The expected outcome for this demo.
feedback	string	yes	Min 1 char. Free-form feedback explaining what was wrong.

provider · string

LLM provider override: "gemini" or "claude".

Example Requests

Refine after a missed detection

{
  "data": {
    "analysisPrompt": "## Objective\nIdentify all broken links on the page.\n\n## Detection Logic\nCheck HTTP status codes for non-2xx responses.",
    "demoFeedback": [
      {
        "demoId": "demo-1",
        "demoTitle": "Mailto link with malformed address",
        "demoHtml": "<a href=\"mailto:invalid email@\">Email us</a>",
        "demoExpected": "detected",
        "feedback": "The agent missed this — malformed mailto links should also count as broken links, not just non-2xx HTTP responses."
      }
    ]
  }
}

Response

Success Response

{
  "result": {
    "status": "success",
    "message": "Prompt refined successfully",
    "data": {
      "refinerResult": {
        "analysis_prompt": "## Objective\nIdentify all broken or non-functional hyperlinks on the page, including malformed mailto and tel links.\n\n## Detection Logic\nFor http(s) URLs, check HTTP status codes for non-2xx responses. For mailto links, validate the email address format. For tel links, validate the phone number format.",
        "response_descriptions": {
          "title": "Brief description of the broken link",
          "severity": "critical for 5xx, high for 4xx and malformed mailto/tel, medium for timeouts, low for redirects",
          "targetText": "The anchor text of the broken link",
          "suggestion": "The correct URL, email address, or phone number"
        }
      }
    }
  }
}

Field	Type	Description
data.refinerResult.analysis_prompt	string	The refined analysis prompt.
data.refinerResult.response_descriptions	object	Updated per-field descriptions for AI response shaping.

Failure Response

{
  "error": {
    "message": "ERROR_MESSAGE",
    "status": "INVALID_ARGUMENT"
  }
}

Errors: INVALID_ARGUMENT (missing required fields, empty demoFeedback array, or any demo entry missing required fields).

{
  "result": {
    "status": "success",
    "message": "Prompt refined successfully",
    "data": {
      "refinerResult": {
        "analysis_prompt": "## Objective\n...\n\n## Detection Logic\n...",
        "response_descriptions": {}
      }
    }
  }
}