Adds more parameters and explanations.

Author: szabosteve

specification/inference/_types/CommonTypes.ts

@@ -770,6 +770,17 @@ export class CustomServiceSettings {
    * ```
    */
   headers?: UserDefinedValue
+  /**
+   * Specifies the query parameters as a list of tuples. The arrays inside the `query_parameters` must have two items, a key and a value.
+   * For example:
+   * ```
+   * "query_parameters":[
+   *   ["param_key", "some_value"],
+   *   ["param_key", "another_value"]
+   * ]
+   * ```
+   */
+  query_parameters?: UserDefinedValue
   /**
    * The request configuration object.
    */

specification/inference/put_custom/PutCustomRequest.ts

@@ -32,6 +32,44 @@ import { InferenceChunkingSettings } from '@inference/_types/Services'
  *
  * The custom service gives more control over how to interact with external inference services that aren't explicitly supported through dedicated integrations.
  * The custom service gives you the ability to define the headers, url, query parameters, request body, and secrets.
+ * The custom service supports the template replacement functionality, which enables you to define a template that can be replaced with the contents of a value that defines that key.
+ * Templates are portions of a string that start with `${` and end with `}`.
+ * The parameters `secret_parameters` and `task_settings` are checked for keys for template replacement. Template replacement is supported in the `request`, `headers`, `url`, and `query_parameters`.
+ * If the definition (key) is not found for a template, an error message is returned.
+ * In case of an endpoint definition like the following:
+ * ```
+ * PUT _inference/text_embedding/test-text-embedding
+ * {
+ *   "service": "custom",
+ *   "service_settings": {
+ *      "secret_parameters": {
+ *           "api_key": "<some api key>"
+ *      },
+ *      "url": "...endpoints.huggingface.cloud/v1/embeddings",
+ *      "headers": {
+ *          "Authorization": "Bearer ${api_key}",
+ *          "Content-Type": "application/json"
+ *      },
+ *      "request": "{\"input\": ${input}}",
+ *      "response": {
+ *          "json_parser": {
+ *              "text_embeddings":"$.data[*].embedding[*]"
+ *          }
+ *      }
+ *   }
+ * }
+ * ```
+ * To replace `${api_key}` the `secret_parameters` and `task_settings` are checked for a key named `api_key`.
+ * 
+ * > info
+ * > Templates should not be surrounded by quotes.
+ * 
+ * Pre-defined templates:
+ * * `${input}` refers to the array of input strings that comes from the `input` field of the subsequent inference requests.
+ * * `${input_type}` refers to the input type translation values.
+ * * `${query}` refers to the query field used specifically for reranking tasks.
+ * * `${top_n}` refers to the `top_n` field available when performing rerank requests.
+ * * `${return_documents}` refers to the `return_documents` field available when performing rerank requests.
  * @rest_spec_name inference.put_custom
  * @availability stack since=8.13.0 stability=stable visibility=public
  * @availability serverless stability=stable visibility=public