Agent Vibes: A Protocol Gateway That Points Cursor and Claude Code at Antigravity, Codex and Kiro
Unified Agent Gateway — Enables Claude Code CLI and Cursor IDE to use free AI backends (Antigravity, Codex) through protocol translation
At a glance
- What is it?
- Agent Vibes is an MIT-licensed TypeScript gateway that speaks Anthropic SSE to Claude Code CLI and ConnectRPC/gRPC to Cursor IDE, then routes those requests to Antigravity, Codex, Claude-compatible or Kiro backends. The protocol work is real, but the project ships with an explicit account-ban warning and a Cursor version pin that moves fast.
- Who is it for?
- Adopt Agent Vibes if you already hold Antigravity, Codex or Kiro credentials and want Cursor and Claude Code CLI to reach them without changing your editor, and if you accept the README's own warning that Antigravity accounts may be banned. Do not adopt it as a production gateway for a team, because the Cursor protocol implementation is pinned to specific Cursor builds (3.15.6 and 3.19.13 appear in the release titles) and will break on the next protocol change.
- Can I use it commercially?
- Yes. MIT is a permissive licence: you can use, modify and sell software built on it, as long as you keep its copyright and licence notices.
- Is it still maintained?
- Yes. The repository last received commits 2 days ago.
- What is it written in?
- Mainly TypeScript, according to GitHub's language statistics.
Answers come from the project's GitHub data, last synced on September 15, 2026, and from our analysis. They are not legal advice.
DEEP OPEN-SOURCE ANALYSIS
The credential mismatch Agent Vibes is built to paper over
Coding agents are now split across two axes that do not line up. The client you like (Cursor, Claude Code CLI) and the backend you have access to (Antigravity, Codex, Kiro, a third-party Anthropic-compatible endpoint) are chosen independently, and neither side speaks the other's protocol. Cursor talks to its own agent channel over ConnectRPC and gRPC. Claude Code CLI talks Anthropic's /v1/messages with server-sent events. Antigravity exposes a Google Cloud Code API. Kiro streams from AWS CodeWhisperer. Agent Vibes sits in the middle and translates.
The target user is not a team building an internal AI platform. It is an individual developer who already has credentials for one of these backends and wants to keep using the editor they are used to. The README's install path confirms this: the recommended option is to paste a prompt into any LLM and have it walk you through downloading a VSIX, installing it, and applying a Cursor patch. That is a consumer-grade onboarding flow, not a platform deployment guide.
Inside the proxy: two client protocols, five backend routes
The architecture diagram in the README shows a single proxy server with an asymmetric job. On the client side it must accept two different wire formats: POST /v1/messages carrying Anthropic SSE for Claude Code CLI, and POST /agent.v1.* carrying ConnectRPC/gRPC for Cursor IDE. On the backend side it fans out by model family. Gemini requests go to Antigravity IDE over the Cloud Code API. Claude requests can go to a Claude-compatible API, to Antigravity, or to Kiro via the AWS CodeWhisperer streaming endpoint. GPT requests go to Codex CLI or to an OpenAI-compatible API.
The interesting part is the Cursor side. The README states that Agent Vibes implements the Cursor protocol directly rather than only proxying it, aligned with Cursor 3.15 message dumps, and that this includes the full streaming tool loop and tool protocol mapping. Non-core RPCs are passed through to the official implementation. That split is a deliberate bet: implement the parts that carry agent behaviour, delegate the rest. It also explains why releases are titled after Cursor versions. When Cursor changes the shape of the agent channel, the implemented half has to be rewritten.
Routing, cooldowns and the account pool
The features table describes routing decisions made on backend availability and model capability, plus native worker and process pools, backend account state, cooldowns, model-level cooldowns, Google, Codex and Kiro quota views, rate-limit views, and multi-account rotation. Read that as an admission about the backends it targets. Free or bundled tiers have limits, and a gateway that fronts several accounts needs to know when one is exhausted before it forwards a request into a 429.
The granularity matters. Cooldowns exist at both the backend level and the model level, which means a single model hitting a limit does not necessarily take the whole account out of rotation. Quota views are exposed per provider (Google, Codex, Kiro) rather than as one aggregate number. That is the right shape for a system where each backend has a different accounting model, but it also means the operator has to watch several dashboards instead of one.
Installing it: VSIX, Node 24, and the Cursor patch
The README gives two install options. Option 1 is the prompt install, aimed at non-developers: you copy a supplied prompt into any LLM and it walks you through environment checks, downloading the correct VSIX from the GitHub Releases page, installing it, and applying the Cursor direct-connection patch. The prompt text itself is in the README and is worth reading before running it, because it names the exact steps the assistant is supposed to follow.
Option 2 is the manual path, and the README shows the shape of it. You install the VSIX for your platform, then open or fully restart Cursor. The documentation states the extension should auto-start the local bridge and keep Cursor on the direct-connection patch by default, controlled by the setting agentVibes.trafficMode=cursorPatch. If the Dashboard reports the patch still needs applying, the README points to Dashboard > API > Cursor IDE Protocol, or the Command Palette entry Agent Vibes: Apply Cursor Bridge Endpoint Patch.
The environment floor is Node.js 24 or higher, per the badge at the top of the README and the repository's stated requirements. The stack is NestJS 11 on Fastify with HTTP/2, written in TypeScript 5. Beyond the extension, the README lists a dashboard, account management, OAuth and token import, manual account JSON editing, SSL certificate generation, legacy forwarding setup, logs, built-in diagnostics, usage and analytics, and update checks. That is a lot of surface area for a v0.1.x project.
The ban warning, and the Cursor version treadmill
Two limitations are stated in the material itself, which is more than most projects admit. The first is the disclaimer: the project is for educational and research purposes, and using the proxy may put your Antigravity account at risk of being banned. That is not a hedge about uptime. It is a statement that the intended use of the backend may not match the terms under which you obtained access. If your Antigravity account is tied to anything you care about, this is the wrong tool for you.
The second is version coupling. Release titles encode both the project version and the Cursor version they target: v0.1.71 and v0.1.70 are tagged Cursor 3.19.13, while v0.1.69 is tagged Cursor 3.15.6. The README's own install prompt asks the assistant to confirm the user is on a compatible Cursor version for the release. That is the maintenance cost made explicit. Cursor updates, the implemented agent channel shifts, and you wait for a matching Agent Vibes release. Claude Code CLI, which uses the documented Anthropic SSE format, is the more stable of the two client paths.
What it is not: a drop-in replacement for LiteLLM
The obvious comparison is a general-purpose LLM proxy such as LiteLLM. LiteLLM normalises many providers behind an OpenAI-shaped API and leaves the client to adapt. Agent Vibes does the opposite. It implements the client protocols natively, including Cursor's ConnectRPC agent channel and its streaming tool loop, and it treats the backends as the variable part. If you want one OpenAI-compatible endpoint for a dozen model providers, LiteLLM covers that ground and Agent Vibes does not.
If your problem is specifically that Cursor or Claude Code CLI cannot reach the backend you have credentials for, a general proxy will not help, because the missing piece is the client-side protocol, not the provider list. That is the narrow gap Agent Vibes fills. The trade is that you inherit a codebase tracking two proprietary protocols at once, and you inherit the account-risk disclaimer that comes with the backends it targets.
Licence, maintenance and what v0.1.x implies
The licence is MIT, per the repository metadata and the badge in the README. That permits commercial use, modification and redistribution with attribution, and it disclaims warranty. It does not grant you any rights to the Antigravity, Codex, Kiro or Cursor services themselves, and the ban disclaimer sits on top of the licence rather than being overridden by it. If you fork and redistribute, the MIT terms travel with the code; the account risk travels with you.
The maintenance signal is the cadence. Three releases appear in the supplied list, dated 2026-08-09, 2026-09-06 and 2026-09-06, with the last two landing about half an hour apart, and the project is still on 0.1.x. Frequent patch releases tied to Cursor versions suggest active tracking of a moving target rather than a settled interface. Budget for upgrades as a recurring task, not a one-time install, and expect to re-apply the Cursor patch after some updates. The README lists built-in diagnostics and update checks, which is the project's own answer to that churn.
Editorial conclusion
Adopt Agent Vibes if you already hold Antigravity, Codex or Kiro credentials and want Cursor and Claude Code CLI to reach them without changing your editor, and if you accept the README's own warning that Antigravity accounts may be banned. Do not adopt it as a production gateway for a team, because the Cursor protocol implementation is pinned to specific Cursor builds (3.15.6 and 3.19.13 appear in the release titles) and will break on the next protocol change. Before installing, verify three things: your Node.js is version 24 or higher, your Cursor build matches the one named in the release you download, and you can complete the OAuth or token import for at least one backend, since the account pool is the component everything else depends on.
Community notes