Models & pricing

This page is for developers choosing a callable model and estimating the likely cost before integration.

OpenAI-compatible endpoints accept either a complete author/model ID or a bare model name. The gateway resolves exact matches from its alias table. For example, gpt-5.4-nano resolves to openai/gpt-5.4-nano, deepseek-v4-flash to deepseek/deepseek-v4-flash, qwen3.5-flash to qwen/qwen3.5-flash-02-23, and claude-haiku-4.5 to anthropic/claude-haiku-4.5. A bare name absent from the alias table is treated as openai/<name>.

Prefer the complete ID in production and inspect the response model field to confirm the resolved ID. Variants are not bare aliases: always write the complete author/model:free or author/model:batch value.

Anthropic and Gemini native endpoints use different namespaces. Anthropic Messages uses native hyphenated names, such as the verified claude-haiku-4-5. The gateway maps a few dotted aliases (claude-opus-4.8 resolves to claude-opus-4-8), but coverage is partial: claude-haiku-4.5 returns 404. OpenAI-compatible IDs such as anthropic/claude-haiku-4.5 are never valid there. Use public GET /anthropic/v1/models for its current list. Gemini accepts Google-native names, such as the verified gemini-3.1-flash-lite; use public GET /v1beta/models for that protocol.

Base URLs and primary endpoints#

OpenAI-compatible calls use the base URL https://api.clssai.com/v1 and accept Bearer, x-api-key, or a ?key= query parameter. Prefer a header: a key in the URL leaks through referrers, proxy logs, and browser history. The Anthropic SDK base URL is https://api.clssai.com without /v1; calls accept x-api-key or Bearer and require anthropic-version: 2023-06-01. Gemini uses https://api.clssai.com/v1beta with x-goog-api-key or ?key= and does not accept Bearer authentication.

List callable model IDs#

GET /v1/models is public, supports ETag and If-None-Match, and returns only id, object, created, and owned_by for each record.

curl https://api.clssai.com/v1/models \
  -H "Content-Type: application/json" \
  -H 'If-None-Match: "your-last-etag"'

{
  "object": "list",
  "data": [
    {"id": "author/model", "object": "model", "created": 1767225600, "owned_by": "author"}
  ]
}

The API directory is the authority for callable IDs. Reference context and token prices below are server-rendered from the same catalog snapshot used by the full model browser. Non-token-priced models show an em dash instead of a token price.

Models by modality#

Common mistakes#

• Include /v1 in the OpenAI SDK base URL.
• Do not infer availability from a model detail URL; use GET /v1/models.
• Prefer a complete author/model ID in production, use the response model field to audit bare-name resolution, and keep :free or :batch in the complete ID.
• Do not send OpenAI-compatible IDs to native Anthropic or Gemini endpoints; use each protocol's public model list.
• Do not treat a displayed reference price as the final charge; see Usage & billing.
• Do not call inference endpoints from browser JavaScript.
• Use the Anthropic SDK base URL without /v1.
• Use cf-ray when tracing inference requests.