Codex Desktop 26.810.41047 returns 400: input[0].tools[0].description is empty with Azure Responses API

What version of the Codex App are you using (From “About Codex” dialog)?

Desktop version: 26.810.41047 Runtime/client version: 0.148.0

What subscription do you have?

Provider: Azure OpenAI / Foundry

What platform is your computer?

Windows

What issue are you seeing?

Invalid 'input[0].tools[0].description': empty string. Expected a string with minimum length 1, but got an empty string instead.

What steps can reproduce the bug?

After updating to Codex Desktop 26.810.41047, requests sent through a custom Azure OpenAI / Microsoft Foundry provider fail with HTTP 400.
The API rejects a dynamically generated tool because its description field is an empty string

What is the expected behavior?

No response

Additional information

Desktop version: 26.810.41047
Runtime/client version: 0.148.0
Provider: Azure OpenAI / Foundry
Endpoint: /openai/v1/responses
Error: input[0].tools[0].description empty_string
First occurrence: 2026-08-14 04:58:32
Last observed: 2026-08-14 07:57:46

The issue is reproducible and has occurred 18 times in the local logs.

Observed failures by model:

gpt-5.6-sol: 10
gpt-5.6-luna: 7
gpt-5.6-terra: 1

Reproduce the failure with Codex Desktop 26.810.41047, Runtime/client 0.148.0, and a custom Azure OpenAI / Microsoft Foundry provider at /openai/v1/responses. Inspect the generated request and local logs around input[0].tools[0].description, using the listed model cases; done means the request is accepted without the empty-description 400 error.