Docs

Two lines. Any tool.

Every tool below needs the same two things: the apmix base URL and your API key. Paste your key once and every snippet on this page is ready to copy.

Base URLs

https://api.apmix.ai/v1OpenAI-compatible
Chat Completions and Responses. Codex, Cursor, OpenCode, Pi, Kimi, Grok, Hermes and SDKs.
https://api.apmix.aiAnthropic-compatible
Messages API. Claude Code and the Anthropic SDKs.

Your setup

Get a key →

API key

Stays in this tab. It is only used to fill the snippets on this page.

Model

Each tool starts with a sensible default. Pick any model from the catalog.

base_url: https://api.apmix.ai
api_key: apx_live_YOUR_KEY
model: claude-sonnet-5

Choose your tool

11 tools

01
Install Claude Code
Needs Node.js 18 or newer. Skip this if it is already on your machine.
Terminal
```
npm install -g @anthropic-ai/claude-code
```
02
Point it at apmix
Claude Code speaks the Anthropic protocol, so the base URL has no /v1. Set the three variables in the terminal you run it from.
```
export ANTHROPIC_BASE_URL="https://api.apmix.ai"
export ANTHROPIC_AUTH_TOKEN="apx_live_YOUR_KEY"
export ANTHROPIC_MODEL="claude-sonnet-5"
```
Paste your key above to fill this in

Make it permanent

Put the same values in ~/.claude/settings.json so every new terminal is ready. The script backs up an existing file first; if you already have settings, merge the env block into them instead of replacing the file.

~/.claude/settings.json

mkdir -p ~/.claude
[ -f ~/.claude/settings.json ] && cp ~/.claude/settings.json ~/.claude/settings.json.bak
cat > ~/.claude/settings.json <<'EOF'
{
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.apmix.ai",
    "ANTHROPIC_AUTH_TOKEN": "apx_live_YOUR_KEY",
    "ANTHROPIC_MODEL": "claude-sonnet-5"
  }
}
EOF

Paste your key above to fill this in

04
Run it
Start Claude Code inside your project. Switch models any time with /model, using any Claude id from the catalog.
Terminal
```
cd your-project
claude
```

Verify

Check that the key works.

List the models your key can reach. A JSON list back means the key and the URL are right; a 401 means the key is wrong or expired.

curl https://api.apmix.ai/v1/models -H "Authorization: Bearer apx_live_YOUR_KEY"

Paste your key above to fill this in

Your tool isn't listed?

Any tool that lets you set an OpenAI or Anthropic base URL works with apmix. Look for a Base URL or Custom provider field, paste the URL and your key, and use a model id from the catalog.

Still stuck? Email support@apmix.ai with the tool name and your request id.

Errors

Every error, its number, and what to do.

The API answers with a standard HTTP status and a JSON body that names the error. The code never changes, so you can match on it; the message is written for humans. Every response also carries an x-apmix-request-id header — quote it when you write to support@apmix.ai.

Two shapes, depending on the endpoint

OpenAI-compatible endpoints (/v1/chat/completions, /v1/responses, /v1/models, /v1/usage)

HTTP/1.1 429 Too Many Requests
x-apmix-request-id: req_5b1f…

{
  "error": {
    "message": "Your monthly allowance is used up. …",
    "type": "insufficient_quota",
    "code": "allowance_exhausted",
    "param": null
  }
}

Anthropic-compatible endpoints (/v1/messages, /v1/messages/count_tokens)

HTTP/1.1 429 Too Many Requests
x-apmix-request-id: req_5b1f…

{
  "type": "error",
  "error": {
    "type": "rate_limit_error",
    "message": "Your monthly allowance is used up. …",
    "code": "allowance_exhausted"
  }
}

StatusCodeWhen it happensWhat to do

400Bad request

400
invalid_json
invalid_request_error
When it happens: The request body could not be parsed as JSON.
What to do: Check quotes, commas and the Content-Type: application/json header.
400
missing_model
invalid_request_error
When it happens: The request has no model field.
What to do: Add a model id from the catalog, e.g. claude-sonnet-4-6-free.
400
bad_request
invalid_request_error
When it happens: The model rejected a parameter (wrong type, unsupported option, content too long).
What to do: Read the message; it repeats the model's reason. Fix the parameter and resend.

401Authentication

401
missing_api_key
authentication_error
When it happens: No key was sent. Every endpoint needs one, including GET /v1/models, because the catalog is scoped to your plan.
What to do: Send Authorization: Bearer apx_live_… (or x-api-key on Anthropic endpoints).
401
invalid_api_key
authentication_error
When it happens: The key does not exist or was deleted.
What to do: Copy it again from Dashboard → API keys, or create a new one.
401
key_expired
authentication_error
When it happens: The key passed the expiry date you set when you created it.
What to do: Create a new key; expiry cannot be extended.

403Permission

403
model_not_in_plan
permission_error
When it happens: The model exists but is above your plan. On the free trial only the free models are open — the ids ending in -free, such as claude-sonnet-4-6-free. The message names the model, the plan it needs and the plan your key is on.
What to do: Call GET /v1/models with the same key — it lists only what your plan can call — or upgrade in Dashboard → Billing.
403
account_suspended
permission_error
When it happens: The account was suspended for breaking the terms.
What to do: Email support@apmix.ai from the address on the account.

404Not found

404
model_not_found
not_found_error
When it happens: The model id is unknown or was retired.
What to do: Use an id from /v1/models or the Models page. Vendor prefixes like anthropic/ are accepted.
404
not_found
not_found_error
When it happens: The path or method does not exist.
What to do: Use POST /v1/chat/completions, POST /v1/responses, POST /v1/messages, GET /v1/models or GET /v1/usage.

429Limits

429
allowance_exhausted
insufficient_quota · rate_limit_error
When it happens: Your monthly weighted tokens are used up. The type is insufficient_quota, like OpenAI's.
What to do: Upgrade in Dashboard → Billing or wait for the renewal date shown on the Overview page.
429
daily_limit_reached
rate_limit_error
When it happens: You reached the daily cap you set yourself in Settings → Limits.
What to do: Raise or remove the cap, or wait for midnight UTC.
429
weekly_limit_reached
rate_limit_error
When it happens: You reached the weekly cap you set yourself in Settings → Limits.
What to do: Raise or remove the cap, or wait for Monday 00:00 UTC.
429
rate_limit_exceeded
rate_limit_error
Safe to retry
When it happens: More than 60 requests in one minute on a single key.
What to do: Wait retry-after seconds. Spread heavy jobs over several keys.
429
upstream_rate_limited
rate_limit_error
Safe to retry
When it happens: The model itself is saturated right now.
What to do: Retry with back-off (1s, 2s, 4s). Nothing was charged.

502Upstream

502
upstream_error
api_error
Safe to retry
When it happens: The model returned a broken or unexpected reply.
What to do: Retry once; if it repeats, try another model. Nothing was charged.

503Unavailable

503
upstream_unavailable
api_error · overloaded_error
Safe to retry
When it happens: The model timed out or is down for maintenance.
What to do: Retry in a moment or switch models. Nothing was charged.
503
no_provider
api_error · overloaded_error
Safe to retry
When it happens: The model has no active route on our side (rare, during maintenance).
What to do: Retry in a few minutes or pick another model.

Errors marked “safe to retry” are transient: wait a second or two, then send the same request again (most SDKs do this automatically on 429 and 5xx). Everything else needs a change on your side first.

Useful response headers

x-apmix-request-id: Unique id of this request. Include it when you email support@apmix.ai.
x-apmix-remaining: Weighted tokens left in your monthly allowance after this request.
x-apmix-weighted-tokens: What this request cost, after the model's multiplier.
retry-after: Seconds to wait; sent with rate_limit_exceeded.