diff --git a/index.d.ts b/index.d.ts
index eee2794..7d2ec98 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -104,6 +104,19 @@ export class InstrumentationMatcher {
 export class Transformer {
   private constructor();
   free(): void;
+
+  /**
+   * The name of the module to transform.
+   */
+  get moduleName(): string;
+
+  /**
+   * The relative file path within the npm package being instrumented.
+   *
+   * @returns {string}
+   */
+  get filePath(): string;
+
   /**
    * Transform JavaScript code and optionally sourcemap.
    *
diff --git a/lib/transformer.js b/lib/transformer.js
index 990686b..663e3cb 100644
--- a/lib/transformer.js
+++ b/lib/transformer.js
@@ -41,6 +41,24 @@ class Transformer {
   /** No-op — freeing resources is not needed for the JavaScript implementation. */
   free () {}
 
+  /**
+   * The npm package name being instrumented.
+   *
+   * @returns {string}
+   */
+  get moduleName () {
+    return this.#moduleName
+  }
+
+  /**
+   * The relative file path within the npm package being instrumented.
+   *
+   * @returns {string}
+   */
+  get filePath () {
+    return this.#filePath
+  }
+
   /**
    * Instruments `code` by injecting diagnostics_channel tracing around the
    * target functions defined by this transformer's configs.