README: images bill to system key (no customUserVars gate); pluginauths inert

README.md

@@ -232,13 +232,14 @@ needed.
   is deliberately NOT in the chat picker (image models are not chat models;
   chat-calling it was the source of the old 500s).
 - **Image generation — two paths**:
-  1. **MCP tool (default, no key ever)**: `inference-image` server (tool
-     `generate_image`) — members select it in the composer's **+** palette
-     and just ask. The server uses the member's `IC_API_KEY` if LibreChat
-     injected one, otherwise sends a **keyless request** (the gateway bills
-     the request; per-member billing is NOT enforced on this path).
-     `customUserVars` were removed from the live yaml on 2026-10-19 —
-     members are never asked for a key.
+  1. **MCP tool (default, no key ever, no gate)**: `inference-image` server
+     (tool `generate_image`) — members select it in the composer's **+**
+     palette and just ask. Images bill to the co-op SYSTEM key
+     (`SYSTEM_IMAGE_KEY`, LiteLLM alias `system-image-fallback`, $5/30d,
+     `regolo/qwen-image` only). No `customUserVars` gate: it made the credential
+     REQUIRED and blocked the whole server for any not-yet-seeded member
+     (first-login gap) before the fallback could run, and v0.8.8 has no
+     optional-flag escape hatch.
   2. **Agent tool**: LibreChat's built-in "OpenAI Image Tools" (env
      `IMAGE_GEN_OAI_BASEURL`/`IMAGE_GEN_OAI_MODEL` → gateway; no admin key,
      members paste their own). Note LibreChat v0.8.8 renders the generated
@@ -266,9 +267,11 @@ member's own portal-provisioned key automatically:
    that feed and upserts, per member with a sandbox account:
    - `keys` collection: `{userId, name: "Inference Co-op", value: encrypt(JSON.stringify({apiKey}))}`
      — consumed by the chat endpoint (`apiKey: "user_provided"` in the yaml).
-   - `pluginauths` collection: `{userId, pluginKey: "mcp:inference-image",
-     authField: "IC_API_KEY", value: encrypt(key)}` — consumed by the MCP
-     `customUserVars` config so image generation bills to the member's team.
+   - `pluginauths` collection: `{userId, pluginKey: "mcp_inference-image",
+     authField: "IC_API_KEY", value: encrypt(key)}` — currently INERT: image
+     generation bills to the system key instead (see Feature notes), so this
+     row is only written for forward-compatibility if per-member image billing
+     is re-enabled later.
    Encryption uses LibreChat's own scheme (`CREDS_KEY`/`CREDS_IV`, AES-256-CBC
    via `@librechat/data-schemas` `encrypt()`), read from the app process env
    (`/proc/1/environ`) because `cloudron exec` sessions don't inherit it.