chore(main): release toolbox-langchain 1.2.0 (#669)

* chore(main): release toolbox-langchain 1.2.0

* chore: update changelog

---------

Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>
Co-authored-by: Anubhav Dhawan <anubhavdhawan@google.com>

Author: release-please[bot]

.release-please-manifest.json

@@ -1,5 +1,5 @@
 {
-  "packages/toolbox-langchain": "1.0.1",
+  "packages/toolbox-langchain": "1.2.0",
   "packages/toolbox-core": "1.2.0",
   "packages/toolbox-llamaindex": "0.7.0",
   "packages/toolbox-adk": "1.2.0"

packages/toolbox-langchain/CHANGELOG.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## [1.2.0](https://github.com/googleapis/mcp-toolbox-sdk-python/compare/toolbox-langchain-v1.0.1...toolbox-langchain-v1.2.0) (2026-07-09)
+
+
+### Features
+
+* add support for stateless MCP 2026 draft and protocol negotiation fallback ([#699](https://github.com/googleapis/mcp-toolbox-sdk-python/issues/699)) ([68263e1](https://github.com/googleapis/mcp-toolbox-sdk-python/commit/68263e138e37125249584ca410f1c1bcf562602a))
+
+
 ## [1.0.1](https://github.com/googleapis/mcp-toolbox-sdk-python/compare/toolbox-langchain-v1.0.0...toolbox-langchain-v1.0.1) (2026-05-18)
 
 

packages/toolbox-langchain/src/toolbox_langchain/version.py

@@ -12,4 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__version__ = "1.0.1"
+__version__ = "1.2.0"