--- title: Claude Code,Codex + Antigravity OAuth: FULLY FREE AI... description: A walkthrough of CLI Proxy API, an open-source tool that wraps Google's Antigravity IDE OAuth session as a local API server compatible with OpenAI, Gemini, and... canonical: https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY! | daily.dev og:description: A walkthrough of CLI Proxy API, an open-source tool that wraps Google's Antigravity IDE OAuth session as a local API server compatible with OpenAI, Gemini, and... og:url: https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw og:image: https://api.daily.dev/og/posts/CZqUvIhHw.png og:image:alt: Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY! og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY! **[AICodeKing](https://daily.dev/sources/aicodeking)** · 8 min read · 6 upvotes · 0 comments ## Summary A walkthrough of CLI Proxy API, an open-source tool that wraps Google's Antigravity IDE OAuth session as a local API server compatible with OpenAI, Gemini, and Claude API formats. This lets developers use frontier models like Claude Opus 4.6 and Gemini 3.1 Pro for free inside tools like Claude Code, Open Code, Codex CLI, and Cline by redirecting API calls through a local proxy. Setup involves installing the proxy, authenticating with a Google account via OAuth, configuring environment variables or config files in each tool, and pointing the base URL to localhost:8317. Rate limits apply per 5-hour window, with Claude models having tighter quotas than Gemini ones. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I use Claude Opus 4.6 for free inside Claude Code instead of paying Anthropic? Install CLI Proxy API, an open-source local server that wraps a Google Antigravity account's OAuth access into Anthropic, OpenAI, and Gemini-compatible API formats. Run the binary with the antigravity login flag to authenticate, then set the ANTHROPIC_BASE_URL to localhost:8317, set an auth token matching your config API key, and map the Opus, Sonnet, and Haiku model environment variables to Antigravity's Claude Opus 4.6 Thinking and Sonnet 4.6 models. _daily.dev surfaces setups like this for developers hunting ways around expensive coding-model subscriptions._ ### What models does Google Antigravity give free access to via OAuth login? A normal Google account logged into Antigravity provides free access to Claude Opus 4.6 Thinking, Claude Sonnet 4.6, Gemini 3.1 Pro (high and low reasoning variants), Gemini 3.5 Flash (multiple effort levels), Gemini 3 Flash, a flash image model, and GPT-OSS-120B, all with generous rate limits reset on a rolling 5-hour window. _Developers comparing free versus paid model access follow updates like this through daily.dev._ ### How can I connect a self-hosted OpenAI-compatible proxy to Codex CLI and OpenCode? For Codex CLI, edit config.toml in the .codex folder to add a custom model provider block with the base URL set to localhost:8317/v1 and wire API set to responses, then choose the desired model. For OpenCode, edit the opencode.json config to add a provider entry with the same base URL and an API key, then select any available model from the model list. _daily.dev helps developers track configuration tricks for wiring custom endpoints into their preferred coding harness._ --- Tags: [#ai-coding](https://daily.dev/tags/ai-coding), [#claude-code](https://daily.dev/tags/claude-code), [#google-gemini](https://daily.dev/tags/google-gemini) [View this post on daily.dev](https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY!","url":"https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw"},"datePublished":"2026-07-18T09:32:25.554Z","dateModified":"2026-09-14T07:02:41.373Z","description":"A walkthrough of CLI Proxy API, an open-source tool that wraps Google's Antigravity IDE OAuth session as a local API server compatible with OpenAI, Gemini, and...","image":"https://i.ytimg.com/vi/sYtNcR9zXvk/sddefault.jpg","thumbnailUrl":"https://i.ytimg.com/vi/sYtNcR9zXvk/sddefault.jpg","isAccessibleForFree":true,"articleSection":"AICodeKing","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"AICodeKing","logo":"https://media.daily.dev/image/upload/s--x7nDUfWj--/f_auto,q_auto/v1768208312/logos/aicodeking","url":"https://daily.dev/sources/aicodeking"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":6},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"ai-coding,claude-code,google-gemini","timeRequired":"PT8M","video":{"@type":"VideoObject","name":"Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY!","description":"A walkthrough of CLI Proxy API, an open-source tool that wraps Google's Antigravity IDE OAuth session as a local API server compatible with OpenAI, Gemini, and...","thumbnailUrl":"https://i.ytimg.com/vi/sYtNcR9zXvk/sddefault.jpg","uploadDate":"2026-07-18T09:32:25.554Z","duration":"PT8M","url":"https://api.daily.dev/r/CZqUvIhHw","embedUrl":"https://www.youtube.com/embed/sYtNcR9zXvk"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"AICodeKing","item":"https://daily.dev/sources/aicodeking"},{"@type":"ListItem","position":3,"name":"Claude Code,Codex + Antigravity OAuth: FULLY FREE AI Coder is CRAZY!"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/claude-code-codex-antigravity-oauth-fully-free-ai-coder-is-crazy--czquvihhw#faq","mainEntity":[{"@type":"Question","name":"How do I use Claude Opus 4.6 for free inside Claude Code instead of paying Anthropic?","acceptedAnswer":{"@type":"Answer","text":"Install CLI Proxy API, an open-source local server that wraps a Google Antigravity account's OAuth access into Anthropic, OpenAI, and Gemini-compatible API formats. 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