unexpected status 404 Not Found: Unknown error - Codex

Quick fix

Change the DeepSeek official API request URL to one that includes /v1, then send the request through Codex again.

Symptom

Error outputCopy

unexpected status 404 Not Found: Unknown error, url: https://api.deepseek.com/responses

Cause

The DeepSeek official API does not support direct requests to the `responses` endpoint; Codex is currently requesting `https://api.deepseek.com/responses`, which returns 404.

Users have confirmed that appending `/v1` to the API request URL resolves this issue.

Fix

1. 1

   In the Codex configuration in CC Switch, append `/v1` to the end of the DeepSeek official API request URL.

2. 2

   Send the Codex request again and confirm it no longer requests `https://api.deepseek.com/responses`.

Affected Versions

ToolCodex

VersionUnknown

PlatformsWindows

Source Issues

This page is distilled from 2 real issues

• #2843CCSwitch 调用 deepseek v4 给codex 桌面端 出现404错误
• #5210unexpected status 404 Not Found: Unknown error, url: https://api.deepseek.com/responses

FAQ

Is there a solution?

Append `/v1` to the end of the API request URL; users have reported that this method works.

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