modelparams.dev
API MCP GitHub

Providers

Alibaba Anthropic Bedrock Cerebras Cohere DeepSeek Fireworks Google Groq Meta MiniMax Mistral Moonshot AI NVIDIA OpenAI Perplexity Thinking Machines Vertex xAI Xiaomi Z.ai

Providers

Alibaba Anthropic Bedrock Cerebras Cohere DeepSeek Fireworks Google Groq Meta MiniMax Mistral Moonshot AI NVIDIA OpenAI Perplexity Thinking Machines Vertex xAI Xiaomi Z.ai
OpenAI Deprecated 2 params

OpenAI GPT-5 API parameters

These are the API parameters modelparams.dev tracks for OpenAI GPT-5 — the settings you send in a request. Each row gives the type, default, valid range or values, and the conditions that gate it. It's the same data the JSON API serves.

This model is deprecated. Shutdown date: 2026-12-11. Suggested replacement: openai/gpt-5.6-sol.

After the parameter count instead — how many weights GPT-5 has? That's a different number, and we don't track it. Here's the difference.

Length 1 param
Parameter Type Default Description Condition
Max completion tokens
max_completion_tokens 		integer (16…+∞) 4096 Maximum number of output tokens the model may generate. —
Reasoning 1 param
Parameter Type Default Description Condition
Reasoning effort
reasoning_effort 		enum (minimal | low | medium | high) "medium" Controls how much reasoning the model should perform before producing an answer. —

OpenAI GPT-5 API parameters in brief

OpenAI GPT-5 documents 2 API parameters, grouped by what they control:

Frequently asked questions

Which API parameters does OpenAI GPT-5 support?
OpenAI GPT-5 accepts 2 API parameters in the request body: max_completion_tokens, reasoning_effort.

Resources

All OpenAI models Glossary Full catalog

GPT-5 — JSON

The full model definition as served by the API. Copy it or open the endpoint directly.

/api/v1/models/openai/gpt-5.json 
{
  "$schema": "https://modelparams.dev/api/v1/schema.json",
  "provider": "openai",
  "authType": "api_key",
  "model": "gpt-5",
  "status": "deprecated",
  "replacement": "openai/gpt-5.6-sol",
  "shutdownOn": "2026-12-11",
  "params": [
    {
      "path": "max_completion_tokens",
      "label": "Max tokens",
      "description": "Maximum number of output tokens the model may generate.",
      "group": "generation_length",
      "type": "integer",
      "default": 4096,
      "range": {
        "min": 16
      }
    },
    {
      "path": "reasoning_effort",
      "label": "Reasoning effort",
      "description": "Controls how much reasoning the model should perform before producing an answer.",
      "group": "reasoning",
      "type": "enum",
      "default": "medium",
      "values": [
        "minimal",
        "low",
        "medium",
        "high"
      ]
    }
  ]
}

Other OpenAI models

ChatGPT 4o Latest 3 params View GPT-3.5 Turbo 3 params View GPT-3.5 Turbo 16K 3 params View GPT-4 6 params View GPT-4 0613 3 params View GPT-4 Turbo 3 params View GPT-4 Turbo 2024-04-09 3 params View GPT-4.1 3 params View GPT-4.1 Mini 3 params View GPT-4.1 Nano 3 params View GPT-4o 3 params View GPT-4o 2024-11-20 3 params View GPT-4o mini 3 params View GPT-5 Chat Latest 1 param View GPT-5 Mini 2 params View GPT-5 Nano 2 params View GPT-5.1 2 params View GPT-5.1 Codex Subscription 3 params View GPT-5.1 Codex Max Subscription 3 params View GPT-5.2 2 params View GPT-5.2 Subscription 3 params View GPT-5.2 Codex Subscription 3 params View GPT-5.3 Codex 2 params View GPT-5.3 Codex Subscription 3 params View GPT-5.3 Codex Spark Subscription 3 params View GPT-5.4 2 params View GPT-5.4 Subscription 3 params View GPT-5.4 Mini 2 params View GPT-5.4 Mini Subscription 3 params View GPT-5.4 Nano 2 params View GPT-5.4 Pro 2 params View GPT-5.4 Pro Subscription 3 params View GPT-5.5 2 params View GPT-5.5 Subscription 3 params View GPT-5.5 Pro 2 params View GPT-5.5 Pro Subscription 3 params View GPT-5.6 2 params View GPT-5.6 Luna 2 params View GPT-5.6 Luna Subscription 3 params View GPT-5.6 Sol 2 params View GPT-5.6 Sol Subscription 3 params View GPT-5.6 Terra 2 params View GPT-5.6 Terra Subscription 3 params View GPT-OSS 120B 6 params View GPT-OSS 20B 6 params View GPT-OSS Safeguard 120B 4 params View GPT-OSS Safeguard 20B 4 params View o1 2 params View o1-mini 2 params View o1-preview 2 params View o3 2 params View o3-mini 2 params View o3-pro 2 params View o4-mini 2 params View

How to use

Building with an AI agent? Hit Copy to grab this whole guide as Markdown and paste it in — or point your agent straight at /llms.txt.

modelparams.dev is an open, community-maintained catalog of model parameters. Each entry shows the knobs you can turn — type, default, range, and the conditions that gate it.

The same model accessed via an API key and via a subscription usually exposes a different set of parameters. We list both as separate entries so the data stays honest.

Catalog API

The full catalog is static JSON, CORS-enabled, served from the edge.

curl https://modelparams.dev/api/v1/models.json

Each entry is keyed by provider/model for API-key variants; subscription variants append -subscription.

If you only need the params for one model contract, use the providerless endpoint. Subscription contracts are model slugs with -subscription. 

curl https://modelparams.dev/api/v1/models/openai/gpt-5.5.json
curl https://modelparams.dev/api/v1/models/openai/gpt-5.5-subscription.json

Single model

curl https://modelparams.dev/api/v1/models/anthropic/claude-opus-4-7.json
curl https://modelparams.dev/api/v1/models/anthropic/claude-opus-4-7-subscription.json

JSON Schema

Every entry validates against a JSON Schema you can use in your editor or pipeline. 

curl https://modelparams.dev/api/v1/schema.json

Add this header to any YAML you author for autocomplete in VS Code: 

# yaml-language-server: $schema=https://modelparams.dev/api/v1/schema.json

Logos

Provider logos are available at /assets/logos/{provider}.svg where {provider} is the provider slug. They use currentColor so they inherit your text color. 

curl https://modelparams.dev/assets/logos/anthropic.svg

Logos are sourced from the models.dev repo (MIT) and used under nominative fair use.

Contribute

The data lives in YAML under models/{provider}/{model}-{auth}.yaml in the GitHub repo. Open a PR; CI validates against the schema and rebuilds.

Edit on GitHub MIT licensed