Tool input validation treating optional fields as required in MCP calls

{
  "name": "PERPLEXITYAI_PERPLEXITY_AI_SEARCH",
  "inputSchema": {
    "type": "object",
    "properties": {
      "frequency_penalty": {
        "type": "number",
        "exclusiveMinimum": 0,
        "description": "..."
      },
      "presence_penalty": {
        "type": "number",
        "minimum": -2,
        "maximum": 2,
        "description": "..."
      },
      "stream": {
        "type": "boolean",
        "description": "..."
      },
      "systemContent": {
        "type": "string",
        "description": "..."
      },
      "userContent": {
        "type": "string",
        "description": "..."
      }
      // ... other optional fields
    },
    "required": ["systemContent", "userContent"],
    "additionalProperties": false
  }
}

Tool input validation failed for PERPLEXITYAI_PERPLEXITY_AI_SEARCH. Please fix the following errors and try again:
- frequency_penalty: Number must be greater than 0
- presence_penalty: Required
- stream: Required

Provided arguments: {...}