mcp: tool schemas omit required when additionalProperties is false

Description

MCP tools advertised to the model set additionalProperties: false without a required array.

McpCatalog.convertTool copies the server schema and then forces additionalProperties: false. If the server omitted required (common for all-optional objects), the wire schema has properties but no required field. Strict OpenAI-compatible validators reject that with errors like 'required' is required to be supplied and to be an array.

The same shape is used for list_mcp_resources / list_mcp_resource_templates, which have an optional server property, additionalProperties: false, and no required.

read_mcp_resource already sets required: ["server", "uri"].

Plugins

None

OpenCode version

dev (c7134cb)

Steps to reproduce

1. Convert an MCP tool whose inputSchema is { type: "object", properties: { server: { type: "string" } } } (no required).
2. Inspect the schema sent to the model: additionalProperties: false, required missing.
3. Send that schema to a strict OA-compat validator (Console Go / Codex).

Screenshot and/or share link

No response

Operating System

Linux

Terminal

n/a (unit-level)