[Bug]: Undefined array key "key" (and "value") in FileSearchComparisonFilter.php

[adatta02]

Description

On the OpenAI API, the File Search Tool / Searching a vector store supports nesting multiple CompoundFilters in the "filters" parameter to create a complex expression.

The library supports creating API requests of that type but when OpenAI returns the data the library errors while trying to parse the "filters" object returned via the API.

The errors you get are:

[Wed Aug 27 15:15:37 2025] PHP Warning:  Undefined array key "key" in /home/ashish/workspace/college-access-poc/vendor/openai-php/client/src/Responses/Responses/Tool/FileSearchComparisonFilter.php on line 40
[Wed Aug 27 15:15:37 2025] PHP Warning:  Undefined array key "value" in /home/ashish/workspace/college-access-poc/vendor/openai-php/client/src/Responses/Responses/Tool/FileSearchComparisonFilter.php on line 42

When the API response "tools" key looks like this:

    "tools": [
        {
            "type": "file_search",
            "filters": {
                "type": "and",
                "filters": [
                    {
                        "type": "and",
                        "filters": [
                            {
                                "type": "ne",
                                "key": "state",
                                "value": "ny"
                            },
                            {
                                "type": "ne",
                                "key": "state",
                                "value": "ca"
                            }
                        ]
                    }
                ]
            },
            "max_num_results": 5,
            "ranking_options": {
                "ranker": "auto",
                "score_threshold": 0.1
            },
            "vector_store_ids": [
                "vs_68a38ae83c288191a1071eeb288e8fb5",
                "vs_68adf7d2880481919bde619efeb1526f"
            ]
        }
    ],

https://platform.openai.com/docs/api-reference/vector_stores/search

Steps To Reproduce

1. Create an OpenAI vector store and add some documents
2. Use the Responses API with a file search tool and a nested filter object like this:

$result = $client->responses()->create([
    'model' => 'gpt-4.1-2025-04-14',
    'input' => $data["search"],
    'instructions' => $data["prompt"],
    'include' => ['file_search_call.results'],
    'temperature' => 0,
    'tools' => [
        [
            'type' => 'file_search',
            'vector_store_ids' => [$data["vector_id"]],
            'filters' => [
                "type" => "or",
                "filters" => [[
                    "type" => "or",
                    "filters" => [
                        [ "type" => "eq", "key" => "state", "value" => "ny" ],
                        [ "type" => "ne", "key" => "state", "value" => "ca" ],
                    ],
                ]],
            ]
        ]
    ]
]);

OpenAI PHP Client Version

v0.16.0

PHP Version

8.3.24

Notes

The issue is in how FileSearchTool and FileSearchCompoundFilter parse the filters that come back from OpenAI in this case.

It looked like some refactoring would need to be done to allow a list of FileSearchCompoundFilter in FileSearchTool as well as allowing FileSearchCompoundFilter to hold FileSearchCompoundFilter children itself.

[iBotPeaches]

This was a PITA to build the first time and it seems its back with a vengeance.

[iBotPeaches]

Okay I took and look and the code doesn't expect the nesting. So the question is do I have to design this into a recursive any depth recursion or can only nest one additional layer.

[iBotPeaches]

Okay I replicate with your sample in a little test I made. I'll see what I can do - iBotPeaches/openai-php-laravel-test@18ed080

[iBotPeaches]

PR up - #670. It should support recursion at any depth for compound/compound depths.

[adatta02]

@iBotPeaches awesome, thank you!!