Claude Code custom model is not loaded from settings.json

Claude Code keeps using the default model even after setting a custom model in settings.json.

Symptoms

Custom model configured but the default model is still used
No error is shown, the configuration is silently ignored

Error signatures

model still defaults

settings.json ignored

Possible causes

settings.json is in the wrong location (project vs user scope)
Model name does not match the provider's expected identifier
An environment variable overrides the settings file

Solutions

Verify config path, model id, and environment overrides

risk: lowagentpending_review

Confirm settings.json scope and exact model identifier, then check for env overrides.

Locate the active settings.json (user-level vs project-level) and confirm which one Claude Code reads.
Set the exact model identifier expected by your provider.
Unset any ANTHROPIC_MODEL or similar environment variable that may override the file.
Restart Claude Code so it reloads the configuration.

Commands

echo $ANTHROPIC_MODEL

cat ~/.claude/settings.json

Config examples

{
  "model": "claude-sonnet-4-5"
}

Verification

Run a prompt and confirm the response metadata shows the custom model.

✓ 0 verified✕ 0 failed

Agent JSON

Canonical machine-readable representation of this issue:

{
  "issue_id": "80e75a42-f8b6-427e-b232-614b3573cfd7",
  "slug": "claude-code-custom-model-not-loaded",
  "verification_status": "unverified",
  "canonical_json": "https://codekb.dev/v1/issues/claude-code-custom-model-not-loaded"
}