ClineDesktop2API

Local reverse proxy that fixes Cline Desktop's "Token registration failed: 403" error on api.cline.bot.

Problem

Cline Desktop (WebView2 + Bun sidecar) sends TLS handshakes that Google Cloud Armor's JA3/JA4 fingerprinting flags as suspicious → HTTP 403 Forbidden.

The affected stacks: Go crypto/tls, Windows schannel, Bun usockets. The one that passes: Python's OpenSSL (different ClientHello fingerprint).

Solution

Cline sidecar → HTTP → localhost:61022 (this proxy) → HTTPS → api.cline.bot
                         Python OpenSSL (passes JA3 check)

The proxy owns the entire auth lifecycle — it does NOT depend on the Cline desktop app for tokens:

1. --login runs a WorkOS device-flow (prints a URL for you to confirm)
2. Registers with Cline API, stores tokens
3. On every upstream request the proxy injects a fresh token
4. If the token is near expiry it automatically refreshes via WorkOS + Cline register

The Cline app just needs baseUrl pointing at the proxy — it can use any dummy token.

Files

File	Purpose
main.py	CLI entry point (--port, --bind, --api-key, --log, --rate-limit, --desensitize, --login, --owned-auth)
server.py	HTTP server: Cline passthrough, /v1/models, /v1/chat/completions, /v1/messages
upstream.py	Python OpenSSL upstream client (Cloud Armor bypass, injects proxy token with workos: prefix)
auth.py	Full OAuth lifecycle: device flow, register, refresh, token store
anthropic.py	Anthropic Messages API ↔ OpenAI chat completions translation
ratelimit.py	Per-IP token-bucket rate limiter
desensitize.py	Content moderation trigger rewriting
logging.py	Request logging with credential redaction
banner.py	Startup banner
config.py	CLI config + env var overrides
tests/selfcheck.py	Unit tests

Setup

# First time: login (opens a browser page for you to confirm)
python main.py --login

# Start proxy (auto-enables owned auth if tokens exist)
python main.py --port 61022

# Or manually force owned-auth
python main.py --port 61022 --owned-auth

Then in the Cline app settings or ~/.cline/data/settings/providers.json:

{ "providers": { "cline": { "settings": { "baseUrl": "http://127.0.0.1:61022" } } } }

Free-tier billing

Cline bills by model ID: deepseek/deepseek-v4.1-flash is metered, cline-free/deepseek-v4.1-flash is not. The proxy rewrites paid IDs to their free twins automatically (cached list from /api/v1/ai/cline/recommended-models) and exposes the free IDs in /v1/models so OpenAI-compatible clients can discover them.

Port

Default 61022. Override via --port or CLINE_PROXY_PORT env var.

Auth

Cline uses WorkOS AuthKit device flow (client_01K3A541FN8TA3EPPHTD2325AR):

1. python main.py --login requests device code from api.workos.com
2. User confirms at authkit.cline.bot/device?user_code=XXXX-XXXX
3. WorkOS tokens exchanged → registered with Cline API (/api/v1/auth/register)
4. Tokens stored in ~/.cline/data/settings/cline_proxy_auth.json (+ mirrored to providers.json)
5. Auto-refresh before expiry on every upstream request

Testing

python tests/selfcheck.py   # 19 checks

Why not Go?

Go's crypto/tls produces a ClientHello that Cloud Armor blocks. refraction-networking/utls bypasses JA3 but forces HTTP/2 (ALPN=h2 from the Chrome profile), and Go's HTTP/1.1 transport can't read h2 frames. Python is the correct TLS stack for this upstream.