Skip to content
CC Switch WikiUnofficial Community Wiki

ERR_BAD_REQUEST api.anthropic.com Claude Code

Quick fix

Turn on "skip the first-install confirmation" in cc-switch and clear the conflicting environment variables to resolve the Claude Code ERR_BAD_REQUEST.

Symptom

Section titled “Symptom”
Error output
Unable to connect to Anthropic services. Failed to connect to api.anthropic.com: ERR_BAD_REQUEST.

Cause

Section titled “Cause”

Configuring cc-switch to run Claude Code on Windows, a request to api.anthropic.com can error with ERR_BAD_REQUEST because the first-install confirmation flow intercepts it, or because of leftover environment variables (ANTHROPIC_AUTH_TOKEN, ANTHROPIC_BASE_URL). Maintainers note that the latest cc-switch resolved this by adding a "skip the first-install confirmation" feature.

Fix

Section titled “Fix”

  1. Update cc-switch to the latest version for the built-in fix.

  2. In the cc-switch interface, find and turn on the "skip the first-install confirmation" option.

  3. Check and unset the ANTHROPIC_AUTH_TOKEN and ANTHROPIC_BASE_URL system environment variables to prevent a configuration conflict.

Affected Versions

Section titled “Affected Versions”
ToolClaude Code
VersionUnknown
PlatformsWindows

Source Issues

Section titled “Source Issues”

This page is distilled from 2 real issues

FAQ

Section titled “FAQ”
Is this error caused by my using a relay, or by the official Claude?
The error is usually unrelated to relay or official API — it comes from the cc-switch first-install confirmation interception or a local environment variable conflict. Follow the steps above to turn on skip-confirmation and clear the environment variables.
Section titled “Related problems”
API Error: 401 authentication_errorCheck the API key field, Base URL, key type, and cc-switch version, so Claude Code actually reads a valid credential.7 issues mergedClaude Official check failed: could not extract base_url - CodexCC Switch proxying and load balancing do not support an official Claude subscription — use a third-party API key. Forcing it errors and risks a ban.4 issues mergedOnly a 200K context window shows in actual use - Claude CodeChange the default model in `~/.claude/settings.json` to the `[1m]` variant, or run `/model claude-opus-4-8[1m]` in the session, to activate the 1M context.5 issues merged

This is an unofficial community wiki with no affiliation to the cc-switch authors or the project itself. Its content is compiled from the project's public GitHub issues. This site distributes no software.