diff --git a/CHANGELOG.md b/CHANGELOG.md
index b593019..3e18983 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,12 @@ incompatibles. Chaque ligne renvoie à un commit dédié (un artefact = un commi
 
 ## [Unreleased]
 
+## [0.36.1] — 2026-06-23  — fix DELETE conversation (body vide)
+### Fixed
+- Client web `req()` : `content-type: application/json` n'est plus envoyé sur
+  les requêtes **sans corps** (DELETE) — Fastify rejetait le body vide
+  (`FST_ERR_CTP_EMPTY_JSON_BODY`). La suppression de conversation fonctionne.
+
 ## [0.36.0] — 2026-06-23  — conversations persistantes (mémoire multi-tour)
 ### Added
 - **`conversations/store.ts`** : store SQLite (conversations + messages) avec
diff --git a/web/src/api.ts b/web/src/api.ts
index cc8df12..e411a1a 100644
--- a/web/src/api.ts
+++ b/web/src/api.ts
@@ -37,7 +37,10 @@ export class ApiError extends Error {
 }
 
 async function req<T>(path: string, token: string | null, init?: RequestInit): Promise<T> {
-  const headers: Record<string, string> = { "content-type": "application/json" };
+  const headers: Record<string, string> = {};
+  // content-type seulement s'il y a un corps : sinon Fastify rejette un body
+  // vide annoncé en application/json (DELETE, etc.).
+  if (init?.body != null) headers["content-type"] = "application/json";
   if (token) headers.authorization = `Bearer ${token}`;
   const res = await fetch(`/api${path}`, { ...init, headers: { ...headers, ...(init?.headers as Record<string, string>) } });
   if (!res.ok) {