diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index e07945e9..4d204362 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-    ".": "3.16.0"
+    ".": "4.0.0"
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0435d627..ce128ee7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Changelog
 
+## [4.0.0](https://github.com/launchdarkly/ldcli/compare/v3.16.0...v4.0.0) (2026-11-05)
+
+
+### ⚠ BREAKING CHANGES
+
+* The production spec renames or removes some API tags. The ai-configs, views-beta, holdouts-beta, release-pipelines-beta, and releases-beta command groups are replaced by agent-control, views, holdouts, and release-pipelines-deprecated. The contexts command group no longer has the delete-instances, list-instances, and search-instances commands.
+
+### Features
+
+* add observability commands to query logs, traces, aggregations, and keys ([#986](https://github.com/launchdarkly/ldcli/issues/986)) ([a34441c](https://github.com/launchdarkly/ldcli/commit/a34441c5afaeb6e7f12797999d335b1e4bfc0fdd))
+* sync the OpenAPI spec with the production spec ([#963](https://github.com/launchdarkly/ldcli/issues/963)) ([43c3ede](https://github.com/launchdarkly/ldcli/commit/43c3ede6a2b95cd4c5e4d1628a4348a277ad2034))
+* **sync:** add projection and problem core ([#987](https://github.com/launchdarkly/ldcli/issues/987)) ([bcc8d30](https://github.com/launchdarkly/ldcli/commit/bcc8d3080a98ce8943196b77cce7e6dbaf557b5d))
+* **sync:** add the adapter core and the Markdown adapter ([#988](https://github.com/launchdarkly/ldcli/issues/988)) ([3b2d454](https://github.com/launchdarkly/ldcli/commit/3b2d45408c5e64b701040c15301324a145d532d3))
+
 ## [3.16.0](https://github.com/launchdarkly/ldcli/compare/v3.15.0...v3.16.0) (2026-11-02)
 
 
diff --git a/PROVENANCE.md b/PROVENANCE.md
index 2c901437..014159e5 100644
--- a/PROVENANCE.md
+++ b/PROVENANCE.md
@@ -9,7 +9,7 @@ To verify build provenance attestations, we recommend using the [GitHub CLI `att
 <!-- x-release-please-start-version -->
 ```
 # Set the version of the package to verify
-PACKAGE_VERSION=3.16.0
+PACKAGE_VERSION=4.0.0
 ```
 <!-- x-release-please-end -->
 
diff --git a/package.json b/package.json
index aae1699a..3b12b068 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@launchdarkly/ldcli",
   "description": "The official command line interface for managing LaunchDarkly feature flags.",
-  "version": "3.16.0",
+  "version": "4.0.0",
   "main": "index.js",
   "scripts": {
     "postinstall": "go-npm install",