{"slug": "stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per", "title": "Stop guessing your AI bill: one endpoint for GPT-5.5, Claude & Gemini at a flat per-call price", "summary": "A developer created ModelisHub, a single OpenAI-compatible endpoint that auto-selects the best LLM (GPT-5.5, Claude Opus 4.8, Gemini 3.1, Grok, DeepSeek) for each request and charges a flat per-call price, eliminating unpredictable per-token billing and the need to manage multiple API keys. The service routes requests via a 'modelis-auto' model name and returns a header indicating which model handled the call, with options to pin specific models or quality tiers.", "body_md": "If you build on top of LLMs, you've probably hit this: you ship a feature, traffic spikes, and the API bill comes back way higher than you expected. Per-token pricing makes costs hard to predict — you're billed by how verbose the model is, not by the value you ship.\n\nI got tired of that (plus juggling three API keys), so here's a setup that fixes both: **one OpenAI-compatible endpoint that auto-picks the best model and charges a flat price per call.**\n\nInstead of calling each provider directly, you point your existing OpenAI SDK at a single gateway and send one model name: `modelis-auto`\n\n. It routes each request to the best model for the task (GPT-5.5, Claude Opus 4.8, Gemini 3.1, Grok, DeepSeek…) and bills a **flat per-call rate** — so your cost is predictable regardless of which model handled it.\n\nIf you already use the OpenAI SDK, this is a one-line change.\n\n``` python\nfrom openai import OpenAI\n\nclient = OpenAI(\n    api_key=\"YOUR_MODELIS_KEY\",\n    base_url=\"https://modelishub.com/v1\",   # the only change\n)\n\nresp = client.chat.completions.create(\n    model=\"modelis-auto\",                    # let it pick the best model\n    messages=[{\"role\": \"user\", \"content\": \"Explain CRDTs in two sentences.\"}],\n)\nprint(resp.choices[0].message.content)\n```\n\nOr with curl:\n\n```\ncurl https://modelishub.com/v1/chat/completions \\\n  -H \"Authorization: Bearer YOUR_MODELIS_KEY\" \\\n  -H \"Content-Type: application/json\" \\\n  -d '{\"model\":\"modelis-auto\",\"messages\":[{\"role\":\"user\",\"content\":\"Hi\"}]}'\n```\n\nThat's it. Your existing code, SDKs, and OpenAI-compatible tools keep working.\n\nFair question — auto-routing shouldn't be a black box. Every response returns a header telling you exactly which model handled the request:\n\n```\nX-Modelis-Routed-Model: claude-opus-4-8\n```\n\nAnd if you want control, you can stay in a quality tier or call a specific model directly:\n\n```\nmodel: \"modelis-auto:premium\"     # stay in a quality tier\nmodel: \"gpt-5.5\"                   # or pin a specific model\n```\n\nThe point isn't \"cheaper than everyone\" — it's **predictable**. With a flat per-call price:\n\nIf your workload is steady, you control prompt/response sizes tightly, and you've already optimized model choice per route, per-token billing can be cheaper. Flat per-call shines when traffic is bursty, prompts vary, or you just don't want to babysit model selection and cost. Pick what fits your reality.\n\nThere's a free tier: [modelishub.com](https://modelishub.com). I'd genuinely love feedback — especially whether predictable pricing actually matters for how you build, or if you prefer per-token control.", "url": "https://wpnews.pro/news/stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per", "canonical_source": "https://dev.to/chenxiao5580cmd/stop-guessing-your-ai-bill-one-endpoint-for-gpt-55-claude-gemini-at-a-flat-per-call-price-3m8a", "published_at": "2026-06-18 16:17:46+00:00", "updated_at": "2026-06-18 16:29:24.486381+00:00", "lang": "en", "topics": ["large-language-models", "developer-tools", "ai-infrastructure", "ai-products", "ai-tools"], "entities": ["ModelisHub", "GPT-5.5", "Claude Opus 4.8", "Gemini 3.1", "Grok", "DeepSeek", "OpenAI"], "alternates": {"html": "https://wpnews.pro/news/stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per", "markdown": "https://wpnews.pro/news/stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per.md", "text": "https://wpnews.pro/news/stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per.txt", "jsonld": "https://wpnews.pro/news/stop-guessing-your-ai-bill-one-endpoint-for-gpt-5-5-claude-gemini-at-a-flat-per.jsonld"}}