agent-browser adds experimental WebMCP support
Introduced 2026-09-01 · score 0.96
HOW TO USE IT
When browsing with locally managed Chrome, discover current-page WebMCP tools with `agent-browser webmcp list` and invoke a selected tool with its parameters. To expose WebMCP through the MCP server, start it with `agent-browser mcp --tools webmcp`; disable WebMCP with `--no-webmcp` or `AGENT_BROWSER_NO_WEBMCP` when needed.
agent-browser open <url>
agent-browser webmcp list
agent-browser webmcp invoke <tool> --params '{"key":"value"}'agent-browser webmcp invoke <tool> --params @input.json --detach
agent-browser webmcp result <invocation-id>
agent-browser webmcp cancel <invocation-id>agent-browser mcp --tools webmcpWHY THIS HELPS
Discover and invoke tools provided by the current page while browsing with locally managed Chrome.
REQUIREMENTS AND LIMITATIONS
- Version: v0.36.0
- Availability: Experimental; WebMCP is enabled by default for locally managed Chrome.
- <url>: Page URL to open; `open` without a URL launches about:blank.
- <tool> (required): Page-provided WebMCP tool name to invoke.
- --params <JSON|@file>: Tool input object as JSON or from a file; no default parameters are documented.
- --detach: Run invocation detached so its result can be retrieved later.
- --tools <profile>: Select MCP server tool profiles; `webmcp` enables page-tool discovery, invocation, detached results, and cancellation. Profiles can be combined; `all` enables every tool.
- --no-webmcp: Disable experimental WebMCP Chrome features; `AGENT_BROWSER_NO_WEBMCP` is the environment-variable alternative.
- Prerequisite: WebMCP is enabled by default for locally managed Chrome.
- Prerequisite: MCP server startup defaults to the `core` tools profile; select `webmcp` explicitly to expose its tools.
- WebMCP applies to locally managed Chrome by default.
- WebMCP can be disabled with `--no-webmcp` or `AGENT_BROWSER_NO_WEBMCP`.
- The MCP tool profile is opt-in.
- Support includes frame-aware tool selection, detached results, cancellation, and bounded metadata and output handling.
FIRST-PARTY EVIDENCE
- https://github.com/vercel-labs/agent-browser/releases/tag/v0.36.0
- https://github.com/vercel-labs/agent-browser/blob/v0.36.0/skill-data/core/references/commands.md
- https://github.com/vercel-labs/agent-browser/blob/v0.36.0/cli/src/mcp.rs
Check the installed version and the source before using it. Entry JSON