fix(client): don't let non-JSON error bodies crash requests

CHANGELOG.md

@@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 > Entries before 1.2.0 were not tracked in this file; see the git history for details.
 
+## [1.4.1] — 2026-08-14
+### Fixed
+- Non-JSON error bodies (e.g. a plain-text `"Service Unavailable"` on a FAMIS 503) no
+  longer crash requests with a raw `SyntaxError`/`"... is not valid JSON"`. The shared
+  axios instance now parses defensively and falls back to the raw string, so
+  `throwResponseError`/`ApiError` always get a real response to work with instead of
+  axios's transform throwing before one exists. (#458)
+
 ## [1.4.0] — 2026-07-17
 ### Added
 - Opt-in **keyset (Id-range-partitioned) parallel paging** for the assets batch fetch.

famis_client.ts

@@ -387,6 +387,24 @@ export class FamisClient {
       // socket, freeing the slot) instead of hanging forever. Per-request, not
       // per-operation — safe for paginated fetches (each page is its own request).
       timeout: requestTimeoutMs,
+      // FAMIS sometimes returns a non-JSON body (e.g. plain-text "Service Unavailable")
+      // on 5xx errors. Axios's default transformResponse can throw a raw SyntaxError in
+      // that case instead of resolving, which skips throwResponseError entirely and
+      // surfaces an unhandled parse error instead of a clean ApiError with the real
+      // status. Parse defensively and fall back to the raw string so every request
+      // resolves to a normal AxiosResponse.
+      transformResponse: [
+        (data: any) => {
+          if (typeof data === 'string' && data.length) {
+            try {
+              return JSON.parse(data);
+            } catch (e) {
+              return data;
+            }
+          }
+          return data;
+        },
+      ],
     });
     if (autoRetry) {
       const RETRIES = 6;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "facility360",
-  "version": "1.4.0",
+  "version": "1.4.1",
   "description": "A Node based 360Facility client SDK",
   "main": "dist/index.js",
   "files": [