diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7cb747779f..996c2126fd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,24 @@
 
 ---
 
+## [3.1.1] — 2026-03-26
+
+### ✨ New Features
+
+- **Vision Capability Metadata**: Added `capabilities.vision`, `input_modalities`, and `output_modalities` to `/v1/models` entries for vision-capable models (PR #646)
+- **Gemini 3.1 Models**: Added `gemini-3.1-pro-preview` and `gemini-3.1-flash-lite-preview` to the Antigravity provider (#645)
+
+### 🐛 Bug Fixes
+
+- **Ollama Cloud 401 Error**: Fixed incorrect API base URL — changed from `api.ollama.com` to official `ollama.com/v1/chat/completions` (#643)
+- **Expired Token Retry**: Added bounded retry with exponential backoff (5→10→20 min) for expired OAuth connections instead of permanently skipping them (PR #647)
+
+### 🧪 Tests
+
+- **936 tests, 0 failures**
+
+---
+
 ## [3.1.0] — 2026-03-26
 
 ### ✨ New Features
diff --git a/docs/openapi.yaml b/docs/openapi.yaml
index 43731c8fe0..9f6aae29c4 100644
--- a/docs/openapi.yaml
+++ b/docs/openapi.yaml
@@ -1,7 +1,7 @@
 openapi: 3.1.0
 info:
   title: OmniRoute API
-  version: 3.1.0
+  version: 3.1.1
   description: |
     OmniRoute is a local-first AI API proxy router. It provides an OpenAI-compatible
     endpoint that routes requests to multiple AI providers with load balancing,
diff --git a/package-lock.json b/package-lock.json
index d82cf970bf..23536523d8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "omniroute",
-  "version": "3.1.0",
+  "version": "3.1.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "omniroute",
-      "version": "3.1.0",
+      "version": "3.1.1",
       "hasInstallScript": true,
       "license": "MIT",
       "workspaces": [
diff --git a/package.json b/package.json
index 0be61613ae..fdba66dd8a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "omniroute",
-  "version": "3.1.0",
+  "version": "3.1.1",
   "description": "Smart AI Router with auto fallback — route to FREE & cheap models, zero downtime. Works with Cursor, Cline, Claude Desktop, Codex, and any OpenAI-compatible tool.",
   "type": "module",
   "bin": {