> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://respan.ai/docs/apis/behaviors/create-custom-behavior/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://respan.ai/_mcp/server. # Create a custom behavior POST https://api.respan.ai/api/pulses/behaviors/custom/ Content-Type: application/json Creates a behavior from a plain-language definition. New spans are scored against it from then on; past spans are not rescored. Reference: https://respan.ai/docs/apis/behaviors/create-custom-behavior ## Authentication - `Authorization` header (bearer token, required) — Use your Respan API key for Respan API authentication. Enter only the Respan API key value; clients send Authorization: Bearer \. For /api/responses, provider credentials such as Perplexity, OpenAI, or Azure OpenAI go in Settings -> Providers or respan\_params.credential\_override in the request body, not in this authentication field. ## Request ### Body (application/json) This endpoint expects a CustomBehaviorCreateRequest. - `description` (string, required) — The plain-language definition span-01 scores each span against. Say what counts and what doesn't. At least 3 characters after trimming. - `name` (string, optional, nullable) — Display name. Optional and not unique. Blank is stored as `null`. - `polarity` (enum, optional) — Whether the behavior firing is good or bad: `negative` (an Issue), `positive` (a Win) or `neutral` (Info). Display metadata only; it does not change how spans are scored. Defaults to `neutral`. - Allowed values: `negative`, `positive`, `neutral` ## Response ### 201 The created behavior. - `id` (string, required) — Custom behavior ID. It is also the behavior's key in analytics, filters and span verdicts. - `name` (string, required, nullable) — Display name. Optional and not unique; behaviors are identified by `id`. - `description` (string, required) — The plain-language definition span-01 scores each span against. Say what counts and what doesn't. At least 3 characters after trimming. - `polarity` (enum, required) — Whether the behavior firing is good or bad: `negative` (an Issue), `positive` (a Win) or `neutral` (Info). Display metadata only; it does not change how spans are scored. - Allowed values: `negative`, `positive`, `neutral` - `created_at` (datetime, required) - `updated_at` (datetime, required) ## Errors ### 400 Bad Request Error Validation failed, or the project is on a legacy plan without a tier and already has 50 custom behaviors. - `map from string to any` ### 403 Forbidden Error Forbidden: the API key is missing, invalid or expired; the key doesn't grant `custom_behaviors:create` (Write access does); behaviors are turned off for the organization. - `detail` (string, required) ### 429 Too Many Requests Error Rate limited. This endpoint allows 30 requests per minute per organization. - `detail` (string, required) ## Examples **Request** ```json { "description": "The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.", "name": "Refund promise", "polarity": "negative" } ``` **Response** ```json { "id": "6f1c2a9e-3b7d-4c55-9a0e-2d8f4b1c7e93", "name": "Refund promise", "description": "The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.", "polarity": "negative", "created_at": "2026-09-28T17:41:09.512340Z", "updated_at": "2026-09-28T17:41:09.512340Z" } ``` **SDK Code** ```python Behaviors_createCustomBehavior_example import requests url = "https://api.respan.ai/api/pulses/behaviors/custom/" payload = { "description": "The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.", "name": "Refund promise", "polarity": "negative" } headers = { "Authorization": "Bearer ", "Content-Type": "application/json" } response = requests.post(url, json=payload, headers=headers) print(response.json()) ``` ```javascript Behaviors_createCustomBehavior_example const url = 'https://api.respan.ai/api/pulses/behaviors/custom/'; const options = { method: 'POST', headers: {Authorization: 'Bearer ', 'Content-Type': 'application/json'}, body: '{"description":"The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.","name":"Refund promise","polarity":"negative"}' }; try { const response = await fetch(url, options); const data = await response.json(); console.log(data); } catch (error) { console.error(error); } ``` ```go Behaviors_createCustomBehavior_example package main import ( "fmt" "strings" "net/http" "io" ) func main() { url := "https://api.respan.ai/api/pulses/behaviors/custom/" payload := strings.NewReader("{\n \"description\": \"The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.\",\n \"name\": \"Refund promise\",\n \"polarity\": \"negative\"\n}") req, _ := http.NewRequest("POST", url, payload) req.Header.Add("Authorization", "Bearer ") 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 Behaviors_createCustomBehavior_example require 'uri' require 'net/http' url = URI("https://api.respan.ai/api/pulses/behaviors/custom/") http = Net::HTTP.new(url.host, url.port) http.use_ssl = true request = Net::HTTP::Post.new(url) request["Authorization"] = 'Bearer ' request["Content-Type"] = 'application/json' request.body = "{\n \"description\": \"The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.\",\n \"name\": \"Refund promise\",\n \"polarity\": \"negative\"\n}" response = http.request(request) puts response.read_body ``` ```java Behaviors_createCustomBehavior_example import com.mashape.unirest.http.HttpResponse; import com.mashape.unirest.http.Unirest; HttpResponse response = Unirest.post("https://api.respan.ai/api/pulses/behaviors/custom/") .header("Authorization", "Bearer ") .header("Content-Type", "application/json") .body("{\n \"description\": \"The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.\",\n \"name\": \"Refund promise\",\n \"polarity\": \"negative\"\n}") .asString(); ``` ```php Behaviors_createCustomBehavior_example request('POST', 'https://api.respan.ai/api/pulses/behaviors/custom/', [ 'body' => '{ "description": "The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.", "name": "Refund promise", "polarity": "negative" }', 'headers' => [ 'Authorization' => 'Bearer ', 'Content-Type' => 'application/json', ], ]); echo $response->getBody(); ``` ```csharp Behaviors_createCustomBehavior_example using RestSharp; var client = new RestClient("https://api.respan.ai/api/pulses/behaviors/custom/"); var request = new RestRequest(Method.POST); request.AddHeader("Authorization", "Bearer "); request.AddHeader("Content-Type", "application/json"); request.AddParameter("application/json", "{\n \"description\": \"The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.\",\n \"name\": \"Refund promise\",\n \"polarity\": \"negative\"\n}", ParameterType.RequestBody); IRestResponse response = client.Execute(request); ``` ```swift Behaviors_createCustomBehavior_example import Foundation let headers = [ "Authorization": "Bearer ", "Content-Type": "application/json" ] let parameters = [ "description": "The assistant promises a refund, credit, or compensation that the policy in the system prompt does not allow.", "name": "Refund promise", "polarity": "negative" ] as [String : Any] let postData = JSONSerialization.data(withJSONObject: parameters, options: []) let request = NSMutableURLRequest(url: NSURL(string: "https://api.respan.ai/api/pulses/behaviors/custom/")! 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() ```