Cursor API Relay Guide - Custom API Keys, OpenAI-Compatible Providers and Risk Checks

Quick answer

Use official provider keys as the safety baseline. Consider an API relay for Cursor only when it documents provider support, model names, pricing, privacy policy and OpenAI-compatible behavior clearly enough for a small non-sensitive test.

Cursor custom API keys are configured from Cursor Settings > Models.
Custom API keys apply to standard chat models; specialized Cursor models may still use Cursor's own models.
Relays need extra checks for model substitution, logging, token billing and refund rules.

Verify before testing a Cursor relay

Official docs or provider pages mention Cursor, OpenAI-compatible APIs or supported model families.
Base URL, API key format, model names, streaming behavior and error format are documented.
Pricing is public enough to compare input/output token costs and failed-request billing.
Privacy, log retention, terms and support channels are visible before sending repository context.
The provider page has a clear update path so missing fields can be corrected by the provider.

Cursor-compatible provider shortlist

This shortlist is based on visible Cursor or OpenAI-compatible signals in the current public-data directory. It is a starting point for verification, not a final recommendation.

Entry	Provider	Type	Best for	Tool compatibility	Public links	Notes	Source / action
Listed 1	MoleAPI moleapi.com	Claude Code friendly	Developers who want one endpoint for Claude Code, Cursor, Codex CLI, and common OpenAI SDK workflows.	Claude Code Codex CLI Cursor Cline	Official Docs Pricing 6/8 sources	Run low-balance test first	Details Website
Listed 2	API易 apiyi.com	Claude Code friendly	Teams that care about documentation, invoices, and visible model/pricing references.	Claude Code Codex CLI Cursor Cline	Official Docs Pricing 5/8 sources	Run low-balance test first	Details Website
Listed 3	灵芽 API api.lingyaai.cn	Claude Code friendly	Users who primarily need copyable setup steps for AI coding terminals and editors.	Claude Code Codex CLI Cursor Cline	Official Docs Pricing 6/8 sources	Run low-balance test first	Details Website
Listed 4	OpenRouter openrouter.ai	Global aggregator	Benchmarking model availability, pricing, and a global API gateway baseline.	Codex CLI Cursor Cline	Official Docs Pricing 7/8 sources	Run low-balance test first	Details Website
Listed 5	302.AI 302.ai	Global aggregator	Users who want both AI tools and API access under one account, while still checking official docs, pricing and privacy links before production use.	Codex CLI Cursor Cline	Official Docs Pricing 7/8 sources	Run low-balance test first	Details Website
Listed 6	SiliconFlow siliconflow.com	China model platform	Low-cost DeepSeek, Qwen, embedding, image, and open model workloads.	Codex CLI Cursor Cline	Official Docs Pricing 7/8 sources	Run low-balance test first	Details Website
Listed 7	柏拉图 AI api.bltcy.ai	Claude Code friendly	Users comparing Chinese relay services with coding-tool setup support.	Claude Code Codex CLI Cursor Cline	Official Docs Pricing needs checking 5/8 sources	Pricing needs checking	Details Website
Listed 8	DMXAPI dmxapi.com.cn	Enterprise gateway	Companies that need private deployment, auditability, and a managed API control layer.	Codex CLI Cursor Cline	Official Docs need checking Pricing needs checking 2/8 sources	Docs need checkingPricing needs checking	Details Website

Official and public sources

These sources anchor the page. Provider-specific claims should still be checked from each provider's current docs and pricing pages.

Cursor API key settings GPT/Codex relay directory Relay risk guide

Cursor's official documentation for custom API keys and supported providers.
OpenAI-compatible providers that may also be useful for Cursor-style workflows.
Privacy, billing and model-substitution risks to check before testing relays.

Provider update and sponsored inquiries

If a Cursor-compatible provider has missing docs, pricing, model coverage, privacy or support fields, use the update path to send public sources. Sponsored placements must be labeled and do not remove risk notes.

Update a listing Risk guide

FAQ

Can Cursor use a custom API key?

Yes. Cursor's official settings documentation describes custom API key configuration under Cursor Settings > Models for supported providers such as OpenAI, Anthropic, Google, Azure OpenAI and AWS Bedrock.

Can every OpenAI-compatible relay work with Cursor?

No. OpenAI-compatible support is only a starting signal. Verify base URL behavior, model names, streaming, pricing, privacy and whether Cursor's exact workflow accepts that provider.

Should I use a relay for sensitive Cursor projects?

Prefer official APIs, cloud-provider routes or self-hosted gateways for sensitive repositories. Test relays only with non-sensitive code and a small balance first.