Browser Use 0.13.10
Release notesA maintenance release. All of it lands in the MCP layer and the dependency list.
Browser Use 0.13.10 shipped on the fourth of September. The MCP layer moves onto a new SDK, tool errors get reported differently, and every dependency now names one exact version.
Browser harness 0.1.13
The upgradesThe browser harness moves up a version
First, the browser harness. That is the component that actually drives Chrome. Browser Use now requires version 0.1.13 of it, one step up from the previous release.
MCP Python SDK 2.1.1
The upgradesMCP jumps a major version
The MCP Python SDK goes from 1.28.1 to 2.1.1. That is a major version, and both the server Browser Use exposes and the client it talks through were rewritten against it.
02 The renames
ChapterThe renames
What your own MCP code has to change.
What your own MCP code has to change.
Fields in snake case
The renamesThree fields switch to snake case
- +inputSchema → input_schema, on a tool definition
- +mimeType → mime_type, on image content
- +isError → is_error, on a tool result
The SDK renamed its fields to snake case. A tool definition's JSON schema, the mime type on image content, and the error flag on a result all answer to a new attribute name now.
Reading the error flag
The renamesThe client trusts the error flag
When a tool result comes back, the client used to look the error flag up defensively and default it to false. It now reads the typed field straight off the result, so a missing flag cannot slip through.
03 Failure and the handshake
ChapterFailure and the handshake
How the server reports trouble, and how it introduces itself.
How the server reports trouble, and how it introduces itself.
Unknown tool calls
Failure and the handshakeAn unknown tool call is now an error
Same message, carried on an error result
Call the Browser Use MCP server with a tool name it does not have, and it used to hand back the words unknown tool as a successful result. Now the same message arrives flagged as an error.
Argument checks
Failure and the handshakeBad arguments come back as errors
- +An empty code string for browser_exec
- +A max_dim that is not a positive integer
The same flag rides on the argument checks. An empty code string, or a screenshot size that is not a positive integer, now comes back marked as an error instead of a plain line of text.
Version at connect
Failure and the handshakeThe server states its version at connect
Version and usage instructions live on the server object
The stdio server now carries the Browser Use version and its usage instructions on the server object itself, and hands both to the client during the opening handshake.
Handler registration
Failure and the handshakeHandlers register by method name
self.server.add_request_handler(
"tools/list", types.PaginatedRequestParams, handle_list_tools
)
self.server.add_request_handler(
"tools/call", types.CallToolRequestParams, handle_call_tool
)Registration moves off decorators. Each handler is attached to a method name, takes a request parameters object, and returns a typed result instead of a bare list of text and image blocks.
04 The dependency list
ChapterThe dependency list
What gets installed alongside it, and at which versions.
What gets installed alongside it, and at which versions.
Exact pins
The dependency listEvery declared dependency names one exact version
runtime · optional · development · build
Every declared dependency is now pinned to one exact version, across runtime, optional, development and build. Two installs a month apart resolve to the same tree.
The pins that move
The dependency listThe pins that change what you get
- +Pydantic: a version range becomes exactly 2.13.5
- +pydantic-settings 2.15.0 joins the runtime dependencies
- +Hatchling 1.32.0 pins the build backend
Pydantic was a range and is now exactly 2.13.5. Pydantic settings moves out of the development list and becomes a runtime dependency, at 2.15.0. Hatchling is pinned for the build itself.
pypdf 6.16.2
The dependency listpypdf 6.16.2 clears three advisories
The PDF parser in the runtime dependency list
pypdf goes to 6.16.2, which clears the three security advisories Dependabot had open against it. It is the PDF parser in the runtime dependency list, so every install picks the fix up.
0.13.10
Release notesEvery code change in this release sits in the MCP layer, so how the agent behaves on a page is unchanged. Pin browser-use to 0.13.10 and the whole tree comes with it.
