# plaingateway

> plaingateway is the free OpenRouter alternative: an LLM API gateway with OpenRouter's API, the same paths, request fields, response shapes and errors.
> One prepaid key reaches every routed model through OpenAI-compatible and Anthropic-compatible endpoints. Tokens cost the provider's list price, with 0% platform fee and no subscription.

## When to use plaingateway

- You call models through OpenRouter, or want to, and want the same model ids with no fee on credits: every model is billed at the provider's list price, with 0% platform fee. Switching is a new base URL and a new key. Numbers: https://plaingateway.com/pricing.md
- You run a coding agent or an SDK client (Claude Code, Codex CLI, Cline, Kilo Code, OpenCode, Cursor, the OpenAI or Anthropic SDK) and want one key for every model.
- You need to know who serves a request: each model is pinned to one named host, and `X-PG-Host` names the host on every response.
- You need the cost of each request: it is in `usage.cost` on every completion.
- You need data kept out of training: plaingateway does not train on request data, and each host's retention policy is in the docs.

When not to use it: you need free tokens (there are none; requests are paid from a prepaid balance or through your own provider keys), a model that is not listed at https://plaingateway.com/models.md, or enterprise features such as SSO, SCIM or guardrails.

## Make a first call

- Base URL (OpenAI-compatible): https://api.plaingateway.com/api/v1
- Base URL for the Anthropic SDK (it appends /v1/messages): https://api.plaingateway.com/api
- Auth header: `Authorization: Bearer <key>`. `X-Api-Key: <key>` also works.
- Key format: `sk-pg-v1-` followed by 64 hex characters.
- Get a key: a human signs up at https://plaingateway.com/signup (one email confirmation click, no card), then creates a key at https://plaingateway.com/settings/keys. The key is shown once. There is no API that creates keys.
- Pay for requests: a human adds credit at https://plaingateway.com/settings/credits. New accounts may get a small starting credit for a test call.
- Model ids are `author/slug`, for example `openai/gpt-5.6-luna`. List the text models with `GET https://api.plaingateway.com/api/v1/models` (no key needed) or see https://plaingateway.com/models. Embedding models are listed apart, at `GET https://api.plaingateway.com/api/v1/embeddings/models` or `GET https://api.plaingateway.com/api/v1/models?output_modalities=embeddings`, and answer only `POST https://api.plaingateway.com/api/v1/embeddings` (https://plaingateway.com/docs/api/embeddings).

```sh
curl https://api.plaingateway.com/api/v1/chat/completions \
  -H "Authorization: Bearer $PLAINGATEWAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "openai/gpt-5.6-luna", "messages": [{"role": "user", "content": "Say hello in five words."}], "max_tokens": 32}'
```

Expected response (200, values vary):

```json
{
  "id": "gen-6f2d0c5e9a1b4c7d8e3f2a10",
  "object": "chat.completion",
  "created": 1700000000,
  "model": "openai/gpt-5.6-luna",
  "provider": "OpenAI",
  "choices": [
    {
      "index": 0,
      "finish_reason": "stop",
      "message": { "role": "assistant", "content": "Hello! How are you today?" }
    }
  ],
  "usage": { "prompt_tokens": 12, "completion_tokens": 11, "total_tokens": 23, "cost": 0.0000156 }
}
```

Response headers: `X-PG-Host` (the serving host), `X-PG-Cost-USD` (the charge in USD, on non-streamed responses; a stream carries it as `usage.cost` in its final usage chunk), `X-Generation-Id` (look it up at `GET /generation?id=`).

Errors are JSON with the HTTP status in `error.code`:

```json
{ "error": { "message": "User not found.", "code": 401 } }
```

401 bad or missing key, 402 balance too low or key spend limit reached, 400 bad request or unknown model id, 404 no host left after routing filters, 408 provider timeout, 413 body over 32 MiB, 429 provider rate limit (with Retry-After), 502 provider error, 503 a gateway store is unavailable (retry). `/messages` returns Anthropic's error shape instead.

## More

- [For AI agents](https://plaingateway.com/docs/overview/agents.md): the whole bootstrap on one page
- [Full docs as one Markdown file](https://plaingateway.com/llms-full.txt)
- [OpenAPI 3.1 description](https://plaingateway.com/openapi.json)
- [Docs](https://plaingateway.com/docs): every page also answers as Markdown with a .md suffix or `Accept: text/markdown`
- [Models and prices](https://plaingateway.com/models): also as Markdown at https://plaingateway.com/models.md, and each model page with a .md suffix
- [Pricing](https://plaingateway.com/pricing.md): the earned bonus credit, fees and top-up rules, with the date they were read

## Docs pages

- [Quickstart](https://plaingateway.com/docs/overview/quickstart.md): Sign up with no card, create a key, send a test call, then add credits when you want more.
- [For AI agents](https://plaingateway.com/docs/overview/agents.md): Everything an AI agent needs to make its first call, on one page.
- [FAQ](https://plaingateway.com/docs/overview/faq.md): Answers about top-ups, hosts, cost and privacy.
- [Image inputs](https://plaingateway.com/docs/overview/image-inputs.md): Send images in chat completions and Messages requests.
- [Models](https://plaingateway.com/docs/overview/models.md): Find model IDs, prices, capabilities and hosts.
- [Principles](https://plaingateway.com/docs/overview/principles.md): How pricing, host choice, compatibility and data handling work.
- [Current key](https://plaingateway.com/docs/api/api-keys.md): Read the calling key's spend limit and usage with GET /auth/key.
- [Chat completions](https://plaingateway.com/docs/api/chat-completions.md): Create a chat completion or stream.
- [Completions](https://plaingateway.com/docs/api/completions.md): Create a legacy text completion.
- [Credits](https://plaingateway.com/docs/api/credits.md): Read total credits and usage.
- [Embeddings](https://plaingateway.com/docs/api/embeddings.md): Turn text into vectors with POST /embeddings, the same request and answer as OpenRouter's.
- [Endpoints](https://plaingateway.com/docs/api/endpoints.md): List the hosts of one model with their prices and measured uptime, latency and throughput.
- [Errors](https://plaingateway.com/docs/api/errors.md): Error bodies, every status the gateway returns, and what to do about each.
- [Generation](https://plaingateway.com/docs/api/generation.md): Look up cost and usage for one request.
- [Headers](https://plaingateway.com/docs/api/headers.md): Authentication, attribution and Anthropic request headers, the host header on every response, and the cost header on every non-streamed response.
- [Messages](https://plaingateway.com/docs/api/messages.md): Create an Anthropic-shaped message.
- [Models](https://plaingateway.com/docs/api/models.md): List model IDs and prices with GET /models, and embedding models with GET /embeddings/models.
- [Responses](https://plaingateway.com/docs/api/responses.md): Create an OpenAI Responses-shaped result.
- [API keys](https://plaingateway.com/docs/auth/api-keys.md): Create, limit, disable and revoke the keys that call the API.
- [Management keys](https://plaingateway.com/docs/auth/management-keys.md): There are no management keys: manage keys in the dashboard.
- [Auto top-up](https://plaingateway.com/docs/billing/auto-recharge.md): Top up by card automatically when the balance falls below a threshold.
- [Bonus and referral credit](https://plaingateway.com/docs/billing/bonus-and-referral-credit.md): The first top-up bonus, bonus credit from small tasks, and the credit a referrer earns.
- [Wallet and top-ups](https://plaingateway.com/docs/billing/credits.md): Add credit to the prepaid wallet and see when usage is charged.
- [Invoices](https://plaingateway.com/docs/billing/invoices.md): Find the invoice for each card payment.
- [Projects](https://plaingateway.com/docs/billing/projects.md): Separate keys, credits, usage and invoices under one sign-in.
- [Refunds](https://plaingateway.com/docs/billing/refunds.md): What a refund or dispute does to your wallet and referral credit.
- [Taxes](https://plaingateway.com/docs/billing/taxes.md): How tax is handled on card payments.
- [Changelog](https://plaingateway.com/docs/changelog.md): Dated changes to the API and the documentation.
- [App attribution](https://plaingateway.com/docs/features/app-attribution.md): Name the app behind a request.
- [Error handling](https://plaingateway.com/docs/features/errors.md): When to retry, and when to stop.
- [Prompt caching](https://plaingateway.com/docs/features/prompt-caching.md): Reuse a long prompt prefix at the cached token price.
- [Rate limits](https://plaingateway.com/docs/features/rate-limits.md): What happens when a host rate limits a request.
- [Reasoning tokens](https://plaingateway.com/docs/features/reasoning-tokens.md): Set how much a model reasons, and read how many tokens it used.
- [Structured outputs](https://plaingateway.com/docs/features/structured-outputs.md): Ask for JSON that matches a schema.
- [Tool calling](https://plaingateway.com/docs/features/tool-calling.md): Let a model call your functions, then send back the results.
- [Usage accounting](https://plaingateway.com/docs/features/usage-accounting.md): See what each request cost and when the wallet is charged.
- [Zero data retention](https://plaingateway.com/docs/features/zero-data-retention.md): Route only to hosts that keep no prompts or outputs.
- [Aider](https://plaingateway.com/docs/integrations/aider.md): Use plaingateway, the free OpenRouter alternative, in Aider: three lines of config, the provider's list price for tokens and nothing on top.
- [Anthropic SDK](https://plaingateway.com/docs/integrations/anthropic-sdk.md): Configure the Anthropic SDK to call plaingateway.
- [Claude Code](https://plaingateway.com/docs/integrations/claude-code.md): Use plaingateway, the free OpenRouter alternative, in Claude Code: one settings block, the provider's list price for tokens and nothing on top.
- [Cline](https://plaingateway.com/docs/integrations/cline.md): Use plaingateway, the free OpenRouter alternative, in Cline: four settings, the provider's list price for tokens and nothing on top.
- [Codex CLI](https://plaingateway.com/docs/integrations/codex-cli.md): Configure Codex CLI to call plaingateway.
- [Continue](https://plaingateway.com/docs/integrations/continue.md): Configure Continue to call plaingateway.
- [Cursor](https://plaingateway.com/docs/integrations/cursor.md): Configure Cursor to call plaingateway.
- [JanitorAI](https://plaingateway.com/docs/integrations/janitorai.md): Use plaingateway, the free OpenRouter alternative, as your JanitorAI proxy: four fields, the provider's list price for tokens and nothing on top.
- [Kilo Code](https://plaingateway.com/docs/integrations/kilo-code.md): Use plaingateway, the free OpenRouter alternative, in Kilo Code: one custom provider, the provider's list price for tokens and nothing on top.
- [LangChain](https://plaingateway.com/docs/integrations/langchain.md): Configure LangChain to call plaingateway.
- [LibreChat](https://plaingateway.com/docs/integrations/librechat.md): Configure LibreChat to call plaingateway.
- [n8n](https://plaingateway.com/docs/integrations/n8n.md): Configure n8n to call plaingateway.
- [Open WebUI](https://plaingateway.com/docs/integrations/open-webui.md): Configure Open WebUI to call plaingateway.
- [OpenAI SDK](https://plaingateway.com/docs/integrations/openai-sdk.md): Configure the OpenAI SDK to call plaingateway.
- [OpenCode](https://plaingateway.com/docs/integrations/opencode.md): Use plaingateway, the free OpenRouter alternative, in OpenCode: paste one provider block, pay the provider's list price for tokens and nothing on top.
- [SillyTavern](https://plaingateway.com/docs/integrations/sillytavern.md): Use plaingateway, the free OpenRouter alternative, in SillyTavern: five connection fields, the provider's list price for tokens and nothing on top.
- [Vercel AI SDK](https://plaingateway.com/docs/integrations/vercel-ai-sdk.md): Configure the Vercel AI SDK to call plaingateway.
- [From Anthropic](https://plaingateway.com/docs/migrate/from-anthropic.md): Move an Anthropic Messages client to plaingateway.
- [From OpenAI](https://plaingateway.com/docs/migrate/from-openai.md): Move an OpenAI client to plaingateway.
- [From OpenRouter](https://plaingateway.com/docs/migrate/from-openrouter.md): Move OpenRouter traffic to plaingateway: base URL, key, model ids, headers, routing fields, cost, errors and what is not supported.
- [Data policies](https://plaingateway.com/docs/privacy/data-policies.md): What plaingateway keeps, and how to limit which hosts see a request.
- [Data Processing Addendum](https://plaingateway.com/docs/privacy/dpa.md): Request a data processing addendum.
- [Provider logging](https://plaingateway.com/docs/privacy/provider-logging.md): Hosts keep data under their own policies.
- [Subprocessors](https://plaingateway.com/docs/privacy/subprocessors.md): Companies that process data for plaingateway.
- [Referral dashboard](https://plaingateway.com/docs/referral/dashboard.md): Find your referral code, link and earnings.
- [How referral works](https://plaingateway.com/docs/referral/how-it-works.md): Share your code and earn credit on the top-ups of accounts you refer.
- [Payouts](https://plaingateway.com/docs/referral/payouts.md): Referral earnings are paid as wallet credit.
- [Referral rules](https://plaingateway.com/docs/referral/rules.md): What blocks or reverses referral credit.
- [Model fallbacks](https://plaingateway.com/docs/routing/model-fallbacks.md): Name other models to try when the first one fails.
- [Model variants](https://plaingateway.com/docs/routing/model-variants.md): Change host order with a :floor or :nitro suffix.
- [Provider routing](https://plaingateway.com/docs/routing/provider-routing.md): Filter and order the hosts that serve a request.