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# Preview a signal set version

POST https://api.runtype.com/v1/signal-sets/{id}/versions/{versionNumber}/preview
Content-Type: application/json

Dry-run one version over an agent’s recent traces: per-signal fire rates, confidences, spans and projected monthly cost. Writes no results; the model calls are billed.

Reference: https://docs.runtype.com/api-reference/runtype-api/signals/preview-a-signal-set-version

## Authentication

- `Authorization` header (bearer token, required) — API key or Clerk session token

## Servers

- `https://api.runtype.com` (Production, default)
- `https://api.runtype-staging.com` (Staging)

## Request

### Path parameters

- `id` (string, required)
- `versionNumber` (integer, required)

### Body (application/json)

This endpoint expects an object.

- `agentId` (string, required) — Run the version over this agent’s most recent completed traces.
- `acknowledgeExternalProcessing` (boolean, optional) — Required for a PHI organization whose set uses a decision model outside Cloudflare Workers AI, after a human confirms.
- `limit` (integer, optional) — Traces to read, default 20, at most 50.

## Response

### 200

Preview

- `costUsd` (double, required) — What this preview spent.
- `evaluated` (integer, required)
- `failed` (integer, required)
- `labelAgreement` (any, required) — Agreement with human labels; null until labels exist.
- `monthlyTraceVolume` (integer, required)
- `notes` (list of string, required)
- `projectedMonthlyUsd` (double, required) — Mean unit cost times the agent’s last-30-day trace volume.
- `samples` (list of map from string to any, required)
- `signals` (list of SignalPreviewReportSignalsItems, required)
- `tracesRead` (integer, required)

## Errors

### 400 Bad Request Error

Invalid request

- `error` (string, required)
- `code` (string, optional) — Stable code, e.g. SIGNAL_SET_INVALID or SIGNALS_EXTERNAL_PROCESSING_UNACKNOWLEDGED.
- `details` (map from string to any, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

### 401 Unauthorized Error

Unauthorized

- `error` (string, required)
- `code` (string, optional) — Stable error code. `insufficient_scope` marks an API key that lacks a scope this request needs.
- `details` (list of ErrorDetailsItems, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

### 403 Forbidden Error

Insufficient permissions, or no organization context

- `error` (string, required)
- `code` (string, optional) — Stable code, e.g. SIGNAL_SET_INVALID or SIGNALS_EXTERNAL_PROCESSING_UNACKNOWLEDGED.
- `details` (map from string to any, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

### 404 Not Found Error

Not found

- `error` (string, required)
- `code` (string, optional) — Stable code, e.g. SIGNAL_SET_INVALID or SIGNALS_EXTERNAL_PROCESSING_UNACKNOWLEDGED.
- `details` (map from string to any, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

### 409 Conflict Error

Conflict, or external processing not yet acknowledged

- `error` (string, required)
- `code` (string, optional) — Stable code, e.g. SIGNAL_SET_INVALID or SIGNALS_EXTERNAL_PROCESSING_UNACKNOWLEDGED.
- `details` (map from string to any, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

### 422 Unprocessable Entity Error

Refused: the agent or organization posture forbids signal evaluation

- `error` (string, required)
- `code` (string, optional) — Stable code, e.g. SIGNAL_SET_INVALID or SIGNALS_EXTERNAL_PROCESSING_UNACKNOWLEDGED.
- `details` (map from string to any, optional)
- `requiredScopes` (list of string, optional) — On `insufficient_scope`: every API key scope this request needs.

## Types

### SignalPreviewReportSignalsItems

- `evaluated` (integer, required)
- `fireRate` (double, required)
- `fired` (integer, required)
- `key` (string, required)
- `meanConfidence` (double, required, nullable)
- `reviewBand` (integer, required)
- `type` (string, required)
- `valueCounts` (map from string to double, required)

### ErrorDetailsItems

- `message` (string, required)
- `code` (string, optional) — Stable Runtype validation code (e.g. MISSING_REQUIRED_FIELD, INVALID_ENUM).
- `path` (string, optional) — Dotted JSON path to the offending field.
- `suggestion` (string, optional) — Actionable hint (allowed values, accepted range, …).

## Examples

**Request**

```json
{
  "agentId": "agt_01HX9KZMQ3FVWPN8BRTD5CJYE"
}
```

**Response**

```json
{
  "costUsd": 0.0042,
  "evaluated": 18,
  "failed": 2,
  "labelAgreement": null,
  "monthlyTraceVolume": 4320,
  "notes": [
    "2 traces failed to evaluate due to missing required span fields."
  ],
  "projectedMonthlyUsd": 0.9072,
  "samples": [
    {}
  ],
  "signals": [
    {
      "evaluated": 18,
      "fireRate": 0.33,
      "fired": 6,
      "key": "hallucination_detected",
      "meanConfidence": 0.87,
      "reviewBand": 2,
      "type": "boolean",
      "valueCounts": {}
    }
  ],
  "tracesRead": 20
}
```

**SDK Code**

```python
import requests

url = "https://api.runtype.com/v1/signal-sets/id/versions/1/preview"

payload = { "agentId": "agt_01HX9KZMQ3FVWPN8BRTD5CJYE" }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.json())
```

```javascript
const url = 'https://api.runtype.com/v1/signal-sets/id/versions/1/preview';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"agentId":"agt_01HX9KZMQ3FVWPN8BRTD5CJYE"}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

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

func main() {

	url := "https://api.runtype.com/v1/signal-sets/id/versions/1/preview"

	payload := strings.NewReader("{\n  \"agentId\": \"agt_01HX9KZMQ3FVWPN8BRTD5CJYE\"\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

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

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

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.runtype.com/v1/signal-sets/id/versions/1/preview")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"agentId\": \"agt_01HX9KZMQ3FVWPN8BRTD5CJYE\"\n}"

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

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://api.runtype.com/v1/signal-sets/id/versions/1/preview")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"agentId\": \"agt_01HX9KZMQ3FVWPN8BRTD5CJYE\"\n}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.runtype.com/v1/signal-sets/id/versions/1/preview', [
  'body' => '{
  "agentId": "agt_01HX9KZMQ3FVWPN8BRTD5CJYE"
}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.runtype.com/v1/signal-sets/id/versions/1/preview");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"agentId\": \"agt_01HX9KZMQ3FVWPN8BRTD5CJYE\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = ["agentId": "agt_01HX9KZMQ3FVWPN8BRTD5CJYE"] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://api.runtype.com/v1/signal-sets/id/versions/1/preview")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```