Debugging an AI API 401 from Your Terminal
An AI API 401 means checking credentials first
A 401 usually means the server did not accept your authentication: the key is missing, malformed, revoked, or intended for a different service. It does not usually mean your prompt is wrong. Before changing models or reinstalling your CLI, reproduce the failure outside your editor.
These commands use Bash, curl, and jq. Fluxo gives you one key and one base URL, https://api.fluxorelay.com, across providers. That makes one pairing especially important: a Fluxo key belongs at Fluxo’s endpoint, not a provider’s direct endpoint.
1. Load the key without putting it in shell history
Paste your key at this hidden prompt. Do not paste it into a command, commit it to a repository, or include it in a screenshot.
read -r -s -p 'Fluxo API key: ' FLUXO_API_KEY; printf '\n'; export FLUXO_API_KEY
Check that the variable exists and contains no whitespace, without printing its value:
if [[ -z "$FLUXO_API_KEY" ]]; then printf 'Key is empty\n'; elif [[ "$FLUXO_API_KEY" =~ [[:space:]] ]]; then printf 'Key contains whitespace; paste it again\n'; else printf 'Key is present, with no whitespace\n'; fi
Copy only the key itself, without surrounding quotes or a Bearer prefix. Export matters: an unexported shell variable will not reach a Python process or CLI launched afterward.
2. Test the base URL and Bearer header with curl
For this walkthrough, use the OpenAI-compatible /v1 routes. Confirm the documented route for your chosen integration; a wrong path normally produces a 404, but gateways can authenticate before checking paths.
export OPENAI_BASE_URL='https://api.fluxorelay.com/v1' — Create a private scratch directory, then capture the response body, headers, and status separately:
umask 077; DEBUG_DIR=$(mktemp -d) — curl --silent --show-error --max-time 30 --dump-header "$DEBUG_DIR/headers" --output "$DEBUG_DIR/body" --write-out 'HTTP %{http_code}\n' --header "Authorization: Bearer $FLUXO_API_KEY" "$OPENAI_BASE_URL/models"
cat "$DEBUG_DIR/body" — A 200 means authentication worked for that route. A 401 means you should inspect the error body before changing anything else. A 403 generally points toward permissions or policy; a 429 generally points toward rate limits or quota. Providers differ, so trust the structured error details over the status alone.
3. Fix the credential and endpoint pairing
- Replace revoked or expired credentials with a newly generated key.
- Keep the Authorization scheme as Bearer, followed by one space.
- Remove duplicate authentication headers added by wrappers or custom middleware.
- Check whether your proxy or gateway strips the Authorization header.
- Restart editor terminals when their inherited environment contains stale credentials.
Do not add curl’s redirect-following option while debugging authentication. Inspect an unexpected redirect first, rather than sending credentials toward an unverified destination. Avoid verbose traces in shared logs because they can expose request headers.
4. Prove a model request works before reopening your editor
If the models route returned a model list, print the exact API identifiers: — jq -r '.data[]?.id' "$DEBUG_DIR/body"
Choose an available identifier corresponding to, for example, Claude Sonnet 5.5 or GPT-6.1 Sol. Display names are not necessarily API identifiers; copy the documented ID rather than inventing a slug.
read -r -p 'Paste the exact model ID: ' MODEL_ID
jq -n --arg model "$MODEL_ID" '{model: $model, messages: [{role: "user", content: "Reply with OK."}]}' > "$DEBUG_DIR/request.json"
curl --silent --show-error --max-time 60 --write-out '\nHTTP %{http_code}\n' --header "Authorization: Bearer $FLUXO_API_KEY" --header 'Content-Type: application/json' --data-binary @"$DEBUG_DIR/request.json" "$OPENAI_BASE_URL/chat/completions"
5. Carry the working configuration into your development tools
For an OpenAI SDK application using the usual environment defaults, export the same credential: — export OPENAI_API_KEY="$FLUXO_API_KEY"
Fluxo works with OpenAI SDKs, Claude Code, Codex, and Gemini CLI, but each tool has its own configuration rules. Match its documented authentication mode and endpoint settings; do not assume every CLI reads OPENAI_BASE_URL.
If curl succeeds but your editor fails, compare environment inheritance, project configuration, and credential precedence. If both fail, leave a note on the contact page after signing in, including the timestamp, endpoint path, status, and redacted error—not your key.
If you want to try this workflow, create a Fluxo account. Usage is billed per real token, including cache reads and writes, with no monthly fee; users also earn a referral share when people they invite pay.
Remove the local debugging files when finished:
rm -r -- "$DEBUG_DIR"