docs: Document API client and runner functionality

docs/get-started/installation/index.mdx

@@ -48,6 +48,27 @@ You should see output in the terminal indicating the progress and results of the
 
 [![Sample test screenshot](./example.png)](./example.png)
 
+## Environment Variables
+
+You can customize Doc Detective's behavior with environment variables.
+
+### DOC_DETECTIVE_API_URL
+
+Override the default Doc Detective API endpoint. Use this for enterprise or custom API deployments.
+
+Default: `https://api.doc-detective.com/v1`
+
+Set the environment variable before running tests:
+
+```bash
+export DOC_DETECTIVE_API_URL=https://custom-api.example.com/v1
+npx doc-detective --input sample.spec.json
+```
+
+This variable only works when you've set an API key with `integrations.docDetectiveApi.apiKey` in your config. When you set an API key, Doc Detective runs tests via the API instead of locally.
+
+For more information, see the [configuration reference](/docs/references/schemas/config) and [integrations options](/docs/references/schemas/integrations-options).
+
 ## Next steps
 
 Next up, take a look at some of the [concepts](/docs/get-started/concepts) native to Doc Detective, check out some of the guided [tutorials](/docs/category/tutorials), or explore how to write [tests](/docs/get-started/tests) and [actions](/docs/category/actions) to automate your documentation testing.

docs/references/schemas/config.md

@@ -25,6 +25,7 @@ logLevel | string | Optional. Amount of detail to output when performing an oper
 runOn | array of object([context](/docs/references/schemas/context)) | Optional. Contexts to run the test in. Overrides contexts defined at the config and spec levels. | 
 fileTypes | array of one of: string, object([File type (custom)](/docs/references/schemas/file-type-custom)), object([File type (executable)](/docs/references/schemas/file-type-executable)) | Optional. Configuration for file types and their markup detection. | ``["markdown","asciidoc","html","dita"]``
 integrations | object([Integrations options](/docs/references/schemas/integrations-options)) | Optional. Options for connecting to external services. | 
+apiMaxWaitTime | integer | Optional. Maximum time in seconds to wait for API-based test execution to complete. Only applicable when `integrations.docDetectiveApi.apiKey` is configured. | `600`
 telemetry | object([Telemetry options](/docs/references/schemas/telemetry-options)) | Optional. Options around sending telemetry for Doc Detective usage. | ``{"send":true}``
 concurrentRunners | integer,boolean | Optional. Number of concurrent test runners. Set to true to use CPU core count (capped at 4).<br/><br/>Minimum: 1 | `1`
 environment | object([Environment details](/docs/references/schemas/environment-details)) | ReadOnly. Environment information for the system running Doc Detective. | 
@@ -157,3 +158,14 @@ debug | one of:<br/>- boolean<br/>- string | Optional. Enable debugging mode. `t
   "debug": "stepThrough"
 }
 ```
+
+```json
+{
+  "integrations": {
+    "docDetectiveApi": {
+      "apiKey": "your-api-key"
+    }
+  },
+  "apiMaxWaitTime": 300
+}
+```

docs/references/schemas/integrations-options.md

@@ -12,6 +12,8 @@ Options for connecting to external services.
 Field | Type | Description | Default
 :-- | :-- | :-- | :--
 openApi | array of unknown | Optional. No description provided. | 
+docDetectiveApi | object | Optional. Configure Doc Detective to run tests via the Doc Detective API instead of locally. When an API key is provided, tests are executed on remote infrastructure. | 
+docDetectiveApi.apiKey | string | Required (if docDetectiveApi is used). API key for authenticating with the Doc Detective API. | 
 
 ## Examples
 
@@ -20,3 +22,11 @@ openApi | array of unknown | Optional. No description provided. |
   "openApi": []
 }
 ```
+
+```json
+{
+  "docDetectiveApi": {
+    "apiKey": "your-api-key-here"
+  }
+}
+```