[FEATURE] settings.json fails silently if malformed

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

We use Amazon Bedrock to run Claude. The cloud authentication is set up in ~/.claude/settings.json typically, but any small problem with the JSON will cause Claude Code to silently ignore the settings.

Proposed Solution

1. Make it obvious to the user that the settings.json is invalid, rather than prompting the user to log in to their Anthropic account.
2. Make the JSON parser a little smarter. Surely we can handle trailing commas in 2026?
3. Switch from JSON to a different format (YAML?) that can handle comments.

Alternative Solutions

Claude Code works fine with Bedrock as-is, but only if the user does everything just right. This adds a lot of friction and frustration to newcomers.

Priority

Medium - Would be very helpful

Feature Category

Configuration and settings

Use Case Example

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Additional Context

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