Session Terminated for OpenAI Responses call

[OliverEberlei]

Hi, thank you for this project.

I set up a test server, which works great using the inspector.
When I add my own MCP server to an OpenAI responses call, it successfully can get the tool list.
But then the session is terminated before the actual tool call. This results in an mcp_protocol_error on the OpenAI side.

The log from my server also shows that the session is terminated before the actual tool call is received. Here is the log, which shows that the session is deleted before the request is received. I am sure I missed something. Can you point me in the right direction to configure it properly?

[2025-07-07 09:46:52] production.DEBUG: GET SSE stream closed. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"}
[2025-07-07 09:46:52] production.INFO: Client disconnected {"clientId":"c8d83df5451575b4a64f0aa8a4ea4c49","reason":"Session terminated by DELETE request"}
[2025-07-07 09:46:52] production.INFO: Session deleted {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"}
[2025-07-07 09:46:53] production.DEBUG: Request received {"method":"POST","path":"/mcp","target":"/mcp"}

[2025-07-07 09:46:51] production.INFO: Client connected {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"} [2025-07-07 09:46:51] production.INFO: Session created {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"} [2025-07-07 09:46:51] production.DEBUG: Message received. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","message":{"PhpMcp\\Schema\\JsonRpc\\Request":{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":[],"clientInfo":{"name":"openai-mcp","version":"1.0.0"}}}}} [2025-07-07 09:46:51] production.DEBUG: Response sent. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","payload":{"PhpMcp\\Schema\\JsonRpc\\Response":{"jsonrpc":"2.0","id":0,"result":{"protocolVersion":"2025-03-26","capabilities":{"logging":{},"completions":{},"prompts":{"listChanged":true},"resources":{"subscribe":true,"listChanged":true},"tools":{"listChanged":true}},"serverInfo":{"name":"Laravel MCP","version":"1.0.0"}}}}} [2025-07-07 09:46:51] production.DEBUG: Request received {"method":"POST","path":"/mcp","target":"/mcp"} [2025-07-07 09:46:51] production.DEBUG: Message received. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","message":{"PhpMcp\\Schema\\JsonRpc\\Notification":{"jsonrpc":"2.0","method":"notifications/initialized"}}} [2025-07-07 09:46:51] production.DEBUG: Request received {"method":"GET","path":"/mcp","target":"/mcp"} [2025-07-07 09:46:51] production.DEBUG: Request received {"method":"POST","path":"/mcp","target":"/mcp"} [2025-07-07 09:46:51] production.DEBUG: Message received. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","message":{"PhpMcp\\Schema\\JsonRpc\\Request":{"jsonrpc":"2.0","id":1,"method":"tools/list"}}} [2025-07-07 09:46:51] production.DEBUG: Response sent. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","payload":{"PhpMcp\\Schema\\JsonRpc\\Response":{"jsonrpc":"2.0","id":1,"result":{"tools":[{"name":"find_shows","inputSchema":{"type":"object","properties":{"bandName":{"type":"string"}},"required":["bandName"]},"description":"Find shows, concercts, and festivals for a band"}]}}}} [2025-07-07 09:46:52] production.DEBUG: Request received {"method":"DELETE","path":"/mcp","target":"/mcp"} [2025-07-07 09:46:52] production.DEBUG: GET SSE stream closed. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"} [2025-07-07 09:46:52] production.INFO: Client disconnected {"clientId":"c8d83df5451575b4a64f0aa8a4ea4c49","reason":"Session terminated by DELETE request"} [2025-07-07 09:46:52] production.INFO: Session deleted {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49"} [2025-07-07 09:46:53] production.DEBUG: Request received {"method":"POST","path":"/mcp","target":"/mcp"} [2025-07-07 09:46:53] production.DEBUG: Message received. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","message":{"PhpMcp\\Schema\\JsonRpc\\Request":{"jsonrpc":"2.0","id":0,"method":"tools/call","params":{"name":"find_shows","arguments":{"bandName":"Metallica"}}}}} [2025-07-07 09:46:53] production.DEBUG: Response sent. {"sessionId":"c8d83df5451575b4a64f0aa8a4ea4c49","payload":{"PhpMcp\\Schema\\JsonRpc\\Error":{"jsonrpc":"2.0","id":0,"error":{"code":-32600,"message":"Invalid or expired session. Please re-initialize the session."}}},"context":{"is_initialize_request":false,"type":"post_json","pending_request_id":"ad3b5f39fee7c6f758751cfd3047e021","status_code":404}}

[OliverEberlei]

I just found this thread in the php-mcp/server issues.
It might be related php-mcp/server#39

I set require_approval to never because I haven't implemented that step properly yet.

Is there a way to disable session management for the server?
I found a related discussion on the OpenAI Forums with a similar issue using the FastMCP python server.
They ended up setting the server to be "stateless"

https://community.openai.com/t/openai-mcp-client-starts-to-fail-when-moving-from-sse-to-streamable-http/1275728/6

mcp = FastMCP("bloomy-mcp", stateless_http=True)

This is obviously a feature of FastMCP, but I wondered if this might be something useful for this server also.

[OliverEberlei]

I just confirmed that this was indeed the issue.

"require_approval" => "never" does not work well yet with OpenAI and this MCP server.

I'll leave this issue here in case anyone else runs into it.

A stateless option is still interesting IMO for servers where subscriptions etc are not needed, like simple knowledgebases.

[nfauchelle]

Hi Oliver

Did you have a work around for it? You mentioned "require_approval" doesn't work well yet, what have you done for now? I don't need auth at the moment as just playing

[OliverEberlei]

Yes, I set require_approval to "always" and do multiple calls to the responses API.

In response.completed I iterate over the outputs to find:
$output->type === 'mcp_approval_request'

If one is present, I create a new request to the responses API with these added parameters

'previous_response_id' => $responseId,

'input' => [
    [
        'type' => 'mcp_approval_response',
        'approve' => true,
        'approval_request_id' => $approvalRequestId,
    ]
],

You get the responseId and approvalRequestId from the previous output.

This way I basically "auto-accept" the approval request and that seems to work with this package