Pay only for scale,
not for POCs.
Validate the idea first. Scale what works.
Designed for creators, founders, and small engineering teams: choose a project directory, connect your Codex account, run a small real test, inspect whether it worked and what it used, and decide whether the idea deserves production investment.
Codex usage itself follows your personal Codex account quota; Sidecar eliminates the upfront cost, complexity, and risk of building surrounding infrastructure before you even know if the workflow is viable.
Runs natively on macOS & Windows • No local server configuration required
< 2 min
to first HTTP 200
0 infra
cloud footprint to start
4 steps
from install to test
100% local
gateway & dashboard
Sidecar Desktop
1. Workspace
~/Projects/client-portal
2. Create key
local-development
3. Sign in
Codex linked
4. Test connection
Ready to dispatch
Project-Scoped Key
60 req/min limit • Optional expiry
Bound Workspace
Folder sandbox verified
Codex Auth Session
Direct upstream session
{
"model": "gpt-6-astra",
"messages": [
{
"role": "user",
"content": "Say hello"
}
]
}
See if it works before you scale it.
Setting up a new AI workflow traditionally means provisioning complex cloud gateways, wiring webhooks, managing hosted secrets, and hoping nothing breaks. Sidecar gets you to a confirmed HTTP 200 in under two minutes with zero infra footprint.
Choose workspace
Point Sidecar to a specific directory like ~/Projects/client-portal. Bound processes stay restricted to this chosen path.
Create scoped key
Create project-scoped API keys with rate limits and optional expiry. Keys are securely stored and verified on your local gateway.
Sign in to Codex
Authenticate your personal Codex account on your machine. Requests dispatch upstream directly to Codex using your personal model entitlement.
One-click test
Click "Test Connection" to fire an immediate test payload. Sidecar confirms local endpoint routing, upstream handshake, and 200 OK status.
Understand cost, latency, and viability in real time.
When proving an AI feature, the biggest unknowns are token usage, unexpected response latency, and cryptic local connection errors. Sidecar surfaces the exact telemetry you need to evaluate if an idea is ready for production.
IDE inline query
Codex model (example) • 1 min ago
412ms (example)
28 tokens (example)
Prototype test completion
Selected model • 4 mins ago
1,240ms (example)
542 tokens (example)
Rapid script loop throttled
Safety bucket preserved quota
12ms (example)
0 tokens billed
Local connection verification
handshake-ping • 14 mins ago
210ms (example)
32 tokens (example)
Plain English Diagnosis
If a local port conflict occurs, your key expires, or upstream auth needs renewal, Sidecar identifies the root cause and provides a clear resolution path.
Use it where you already work.
Sidecar acts as an OpenAI-compatible local API endpoint. Connect your existing editors, scripts, or prototype frontends to validate ideas rapidly.
VS Code
Configure your standard AI extension to point directly to Sidecar's local endpoint for interactive chat and completion testing.
http://127.0.0.1:3081/v1/chat/completions
Cursor & Cline
Use standard OpenAI-compatible API base URL and your scoped safe key for seamless inline editor queries and suggestions.
Browser Prototypes
Test client-side JavaScript experiments against local AI streaming without exposing upstream credentials in browser devtools.
cURL & Scripts
Run deterministic test scripts or benchmarks locally before building any complex deployment pipelines.
curl http://127.0.0.1:3081/v1/models
Private by default.
When evaluating early ideas, you should never have to compromise confidentiality or send unvetted workspace data through unfamiliar third-party proxies.
Runs on your computer
The desktop gateway and dashboard run locally on your computer by default. Traffic dispatches upstream straight to Codex.
Strict folder boundaries
Authorized tools are confined strictly to your chosen project workspace. Your personal files and system paths remain unreachable.
Project-scoped keys
Project-scoped API keys with rate limits and optional expiry. Keys are securely stored and verified on your local gateway.
In-memory metadata only
Request history stores volatile metadata only (timestamp, model, status, latency, token count) in local memory and never stores prompts, completions, or credentials.
On our roadmap
Upcoming features focused on making local AI validation even more frictionless.
Broader provider adapters
Connecting additional AI accounts with the same local boundary safeguards.
Standalone background daemon
Quiet background operation that activates whenever your IDE queries the local port.
One-line automated installers
Streamlined single-command installer packages for immediate desktop onboarding.
Deeper IDE extensions
Direct one-click connection extensions for auto-configuring editor base URLs.
Ready to validate your AI idea without infra overhead?
Download Sidecar for macOS & Windows, connect your Codex account, and test your first proof of concept locally today.