Problem

Closes #4211

browser_click in the MCP server uses oneOf at the top level of inputSchema to express "provide either index OR coordinate_x+coordinate_y":

{
  "type": "object",
  "properties": { ... },
  "oneOf": [
    {"required": ["index"]},
    {"required": ["coordinate_x", "coordinate_y"]}
  ]
}

Claude's API (and other strict MCP clients) rejects oneOf/allOf/anyOf at the top level of a tool input schema:

400 tools.N.custom.input_schema: input_schema does not support oneOf, allOf, or anyOf at the top level

This cascades — it breaks all MCP tools in the session, not just browser_click.

Fix

Remove the oneOf block. The constraint is now expressed in the property descriptions instead. No behaviour change: the runtime guard in _click() already returns a clear error string when neither index nor coordinates are provided.

Diff summary

• -4 lines: remove the oneOf: [...] block entirely
• +3 lines: update the three property descriptions to say "Provide this OR ..."

The _click() handler is untouched.

Summary by cubic

Remove the top-level oneOf from the browser_click tool schema to stop Claude and other strict MCP clients from rejecting the tool and breaking the session. No behavior change; validation stays in _click(), and field descriptions now explain using index or coordinate_x+coordinate_y.

^{Written for commit 217b451. Summary will update on new commits.}