[BUG] Browser pane get_page_text: schema says tabId is optional (defaults to fronted tab) but validation requires it

Environment

• Claude Code desktop app 2.1.215 (macOS, Darwin 25.3.0)
• Tool: mcp__Claude_Browser__get_page_text (in-app Browser pane MCP)

Description

The tool schema for get_page_text describes tabId as optional:

tabId: "Tab to act on within the preview context (default: the fronted tab). \"main\" is the primary view."

But calling the tool without tabId fails server-side validation:

MCP error -32602: Input validation error: Invalid arguments for tool get_page_text: [
  {
    "expected": "string",
    "code": "invalid_type",
    "path": ["tabId"],
    "message": "Invalid input: expected string, received undefined"
  }
]

Steps to reproduce

1. Open the Browser pane in a Claude Code desktop session.
2. Have the model call get_page_text with no arguments.

Expected

The call succeeds against the fronted tab, as the schema's default documents. (Or, if tabId is truly required, the schema should mark it required so the model passes it on the first try.)

Actual

Validation error above. The model has to burn a retry with an explicit tabId: "main".

The workaround is easy once you know it, but the schema/validator mismatch guarantees a wasted tool call for any model that trusts the schema.

🤖 Filed with Claude Code