Dify with Claude and GPT: every field of the OpenAI-API-compatible plugin, explained

A developer running the APIVAI gateway published a field-by-field guide to configuring Dify's official openai_api_compatible plugin (v0.0.68) and anthropic plugin, covering the API Base URL, model ID, context size, function-call and API-type settings needed to route Claude and GPT models through a single OpenAI-compatible endpoint. The writeup notes that Dify validates each model with a test request before saving and that the Anthropic plugin appends /v1/messages itself, so the address field should omit that path. It also cites gateway pricing of $1.26/$6.32 per million input/output tokens for Claude Sonnet 4.6 versus Anthropic's official $3/$15.

Disclosure: I run APIVAI, the gateway used in the examples below. The setup is the same for any endpoint that speaks the OpenAI or Anthropic format. Dify https://docs.dify.ai is an open-source platform for building LLM apps: chatbots, agents, workflows and knowledge-base RAG apps. It reaches models through model provider plugins, and with a third-party gateway there are enough fields that it's easy to fill one in wrong. This post goes through the actual fields of Dify's official openai api compatible plugin version 0.0.68 and the anthropic plugin. | Plugin | Address field | Models | Best for | |---|---|---|---| | OpenAI-API-compatible | API Base URL: https://api.apivai.com/v1 | Claude and GPT | One provider for every model; you type the model IDs | | Anthropic | API URL: https://api.apivai.com | Claude only | Claude only, in the native format with prompt caching | Start with OpenAI-API-compatible : you type each model ID yourself, so a new model works as soon as the gateway lists it. Providers live on the Model Provider page: under Integrations in current Dify Cloud, under Settings in the account menu in older self-hosted versions. Each provider applies to the whole workspace, and only owners and admins can change it. Open Model Provider , find OpenAI-API-compatible in the list of providers you can install or on the Dify Marketplace https://marketplace.dify.ai/ and click Install . On the OpenAI-API-compatible card, click Add Model and fill in: | Field | Value | |---|---| | Model Type | LLM | | Model Name | claude-sonnet-4-6 the exact model ID | | Model display name | optional, e.g. "Claude Sonnet 4.6" | | API Key | your key | | API Base URL | https://api.apivai.com/v1 | | model name for API endpoint | leave empty | | Completion mode | Chat | | Model context size | no larger than the model's context window | | Upper bound for max tokens | 8192 or more | | Function Call Type | Tool Call | | Stream function calling | Support | | API Type | Chat Completions API /chat/completions | Leave the rest at their defaults. Older versions of the plugin call the address field API endpoint URL ; the value is the same. The fields people most often misread: When you click Save , Dify sends a test request and only saves if it passes. Repeat Add Model for each model you want, with the same key and address, for example gpt-5.5 and claude-haiku-4-5 . Take model IDs from the API: curl https://api.apivai.com/v1/models -H "Authorization: Bearer your-key" https://api.apivai.com . Do /v1 ; the plugin's Anthropic client appends /v1/messages itself. Leave claude-sonnet-4-6 ; others have different or dated names. If a model is missing or returns "model not found", click claude-haiku-4-5 or gpt-6-luna claude-sonnet-5-5 claude-opus-5-5 A routing workflow a cheap model classifies first, then hands the hard cases to a strong one is the most common way to keep Dify costs down. https://api.apivai.com/v1 , without /chat/completions ; the Anthropic plugin needs At the time of writing, most Claude models on APIVAI are 56–58% below Anthropic's list prices and GPT models up to 86% below OpenAI's; for example, Claude Sonnet 4.6 is $1.26 / $6.32 per million input / output tokens against the official $3 / $15. It's prepaid and billed per token, with no subscription. The full table is at https://apivai.com/pricing https://apivai.com/pricing . Questions are welcome in the comments.