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HTTP 401 Unauthorized - CC Switch Anthropic

Quick fix

Upgrade cc-switch to a fixed build so it sends the x-api-key and anthropic-version headers Anthropic requires.

Symptom

Section titled “Symptom”
Error output
fetch_models returns 401 for Anthropic-compatible endpoints due to missing auth headers

Cause

Section titled “Cause”

The cc-switch `fetch_models` function sends only an `Authorization: Bearer <key>` header by default when fetching a model list. But Anthropic-compatible endpoints (`api.anthropic.com` or a third-party provider) require `x-api-key: <key>` and `anthropic-version: 2023-06-01` as well. Missing those necessary auth headers, the server returns HTTP 401 Unauthorized.

This was resolved in a downstream branch (SaladDay/cc-switch-cli) by introducing a `ModelFetchStrategy` enum that sends the right header combination per provider type: a Bearer token for OpenAI style, Bearer plus x-api-key plus the version header for Anthropic style, and x-goog-api-key for Gemini style.

Fix

Section titled “Fix”

  1. Check whether your cc-switch version has merged the upstream or SaladDay branch fix. If you are on an official build that has not been updated, try a build containing this fix (the SaladDay branch, for example).

  2. If you cannot change build, make sure the API key in your Anthropic config is set correctly as a workaround, and be aware that Fetch Models by hand may still fail, so enter model names manually.

Affected Versions

Section titled “Affected Versions”
ToolClaude Code / Codex
Version3.14.1
PlatformsWindowsmacOSLinux

Source Issues

Section titled “Source Issues”

This page is distilled from 2 real issues

FAQ

Section titled “FAQ”
I configured a local proxy address — why do I still get 401?
Issue #2514 mentions a user configuring a local CPA reverse proxy address while the error pointed at the official OpenAI address. That usually means cc-switch did not apply the custom baseUrl config correctly, or the proxy itself does not pass authentication through properly. Check baseUrl is set correctly in the config file, and that the proxy forwards the specific headers Anthropic needs (x-api-key and so on).
How do I specify a model by hand to avoid Fetch Models failing?
When fetch_models fails with a 401, enter the model name directly in the cc-switch config screen or config file ('claude-sonnet-4-20250514', for example), with no need for the automatic fetch.
Section titled “Related problems”
Gtk-CRITICAL: gtk_widget_get_scale_factor failedOn a GTK assertion failure running cc-switch under Linux or WSL2, edit settings.json to turn silent startup off, or clean the leftovers and reinstall.3 issues mergedmodel is not supported when using CodexDisable cc-switch proxy takeover to avoid writing unsupported model IDs to Codex, preventing official subscription bans or request rejections.2 issues merged"Not logged in ? Please run /login" ClaudeEnable "API Proxy Takeover" in cc-switch when using hosted accounts like Copilot or Codex; direct upstream connections cause auth failures.2 issues merged

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