OpenAI invalid tool schema - array missing items and invalid tool name containing double '--' #36
Description
Was trying to use this MCP server with https://5ire.app/ (OpenAI) and getting following error:
Invalid schema for function 'apifyactors--apify--rag-web-browser': In context=('properties', 'outputFormats'), array schema missing items.
OpenAI tool parameters -> properties do support array type but then items needs to be specified to be clear about inner array type. See https://platform.openai.com/docs/guides/function-calling?example=get-weather -> https://json-schema.org/understanding-json-schema/reference/array
For example for xx this input property causes the error: is array and does not have items set;
{
"title": "Output formats",
"description": "Select one or more formats to which the target web pages will be extracted and saved in the resulting dataset.",
"type": "array",
"default": [
"markdown"
]
}
Should be:
{
"title": "Output formats",
"description": "Select one or more formats to which the target web pages will be extracted and saved in the resulting dataset.",
"type": "array",
"items": {
"type": "string"
},
"default": [
"markdown"
]
}
Also there is an issue with tool naming where we use '--' in the tool name, some clients like the https://5ire.app/ uses '--' to separate MCP client namespace and the tool name: see https://github.com/nanbingxyz/5ire/blob/100f9517bda87a5a11b31527437a6e21c1a4c23d/src/intellichat/services/NextChatService.ts#L214; So we should change this to something else if possible if we want to support as many clients possible
Other issue while working with https://5ire.app/ was the default 60 seconds MCP client tool call timeout, for example the RAG browser was too slow to respond and I had to override the default MCP client timeout in the source code.