dsh-subscription-antigravity
Reuse a Google Antigravity subscription (Google AI Pro / Ultra) as model
providers in DeepSeek Harness.
Authorize one or more Google accounts once; the plugin provisions an
antigravity model route with Gemini, Claude, and GPT-OSS models from Cloud
Code Assist and serves them through a loopback OpenAI-compatible proxy.
Protocol shape follows the
pi-antigravity reference
implementation. Unofficial integration — not affiliated with or endorsed by
Google. Use only with an account and services you are authorized to access.
Install
npx --yes github:shaomingbo/dsh-subscription-antigravity#v0.2.1
The no-argument installer adds the bundle to the web profile (fixed tag
source, pnpm install --ignore-scripts, atomic manifest writes, rollback on
dependency-install failure). It never stops or restarts DSH — when it finishes,
restart DSH manually and hard-refresh the Web GUI.
Other commands:
npx --yes github:shaomingbo/dsh-subscription-antigravity#v0.2.1 status
npx --yes github:shaomingbo/dsh-subscription-antigravity#v0.2.1 uninstall
Options: --profile <name> (default web), --source <spec>, --help.
Environment: DSH_ANTIGRAVITY_SOURCE overrides the package source.
Local development (link:)
npx --yes github:shaomingbo/dsh-subscription-antigravity#v0.2.1 install \
--source link:/Users/you/open-source/dsh-subscription-antigravity
A link: source is for development only; switch back to the fixed tag for
normal use.
Manual fallback
Edit ~/.dsh/profiles/web/package.json by hand: add
"dsh-subscription-antigravity": "github:shaomingbo/dsh-subscription-antigravity#v0.2.1"
to dependencies and "dsh-subscription-antigravity" to
dsh.profile.bundles, then run pnpm install --ignore-scripts in the profile
directory. Restart DSH and hard-refresh afterwards.
Accounts, quota, and switching
- Open Settings → Antigravity and choose Add Google account. Google is
asked to show its account chooser; OAuth uses PKCE and the callback server
listens only on
localhost:51121.
- Repeat to build a local account pool. Each account card shows its email,
active state, project, lowest known remaining quota, reset time, and an
expandable runtime-model quota list.
- Choose Use this account to switch immediately without another OAuth
flow. In-flight requests stay on their original account; new requests use
the active one.
- Optional Automatically switch on exhausted quota is off by default. When
enabled it rotates only after an explicit quota-exhausted 429; ordinary rate
limits, auth errors, network failures, and 5xx responses never trigger it.
A newly added account becomes active. Removing one deletes only that local
credential; removing the active account selects the next saved account. The
single antigravity entry in the DSH model picker always uses the active
account. Existing v1 single-account files migrate automatically without a new
sign-in.
For a remote/headless browser, paste the full callback URL
(http://localhost:51121/oauth-callback?…) into the field provided. Requested
Google scopes: aicode, cloud-platform, userinfo.email, userinfo.profile,
cclog, experimentsandconfigs; review them before approving.
Models
Public model ids mirror the Antigravity CLI catalog; each exposes only the
thinking levels the backend advertises (thinking effort maps to the backend's
runtime ids — see SPEC.md):
| Model | Input | Thinking |
|---|
gemini-3.8-flash | text, image | low / medium / high |
gemini-3.7-flash | text, image | low / medium / high |
gemini-3.6-flash | text, image | low / medium / high |
gemini-3.5-flash | text, image | low / medium / high |
gemini-3.1-pro | text, image | low / high |
claude-sonnet-4-6 | text, image | high |
claude-opus-4-6 | text, image | high |
gpt-oss-120b | text | medium |
Model availability, entitlement, and quota are account-dependent. Gemini
3.8 Flash works by presenting the agy CLI request fingerprint (older
VS Code extension headers get the legacy catalog instead), with transparent
fallback to Gemini 3.7 Flash should a runtime id ever 404. Settings
fetches quotaInfo separately for every saved account; these are best-effort
runtime-model snapshots, not a promise that different models share one pool.
How it works
flowchart LR
A["llm-pi-ai Antigravity route"] --> B["Loopback proxy 127.0.0.1:51122"]
B -->|streamGenerateContent| C["Cloud Code Assist daily endpoint"]
D["Google OAuth PKCE"] --> E["Local account pool"]
E --> F["Active account router"]
F --> B
- The plugin provisions (and repairs) one route in
llm-pi-ai.providers via
the settings service — per-provider merge; your own edits to models are
preserved, and other providers are never touched.
- The proxy binds
127.0.0.1 only and translates OpenAI chat completions
(streaming SSE and JSON) into Cloud Code Assist envelopes, including tool
calls, image inputs, thinking → reasoning_content, and quota-friendly
error mapping. Override the port with DSH_ANTIGRAVITY_PROXY_PORT.
- Each generation request snapshots one account's token and project, so a
manual switch cannot mix identities inside an in-flight request. Optional
quota failover is serialized to avoid concurrent switch storms.
- The active access token syncs into the ordinary credentials seam
(
ANTIGRAVITY_ACCESS_TOKEN); an empty pool removes the seam value.
- Usage-based billing and non-Google endpoints are out of scope.
Credential safety
- OAuth tokens live only in the versioned account pool at
$DSH_HOME/.antigravity-auth.json (0600, atomic writes). They are never sent
to the browser RPC, logged, or exported, and go only to Google's OAuth and
Cloud Code Assist endpoints. Upstream error text is redacted and bounded.
- Uninstall keeps the credential file. Delete
$DSH_HOME/.antigravity-auth.json yourself for a full wipe.
- The installer only edits the profile
package.json (dependency + bundle
entry); it never reads credentials, never runs lifecycle scripts, and never
stops/restarts DSH.
Development
npm install # test-only tooling; the plugin itself has zero runtime deps
npm run check # syntax checks + full test suite
npm test
The test suite covers the installer contract (temporary DSH_HOME installs,
repeats, status, uninstall, malformed manifests, argument errors, rollback),
v1→v2 credential migration, multi-account OAuth and refresh isolation,
quota-only failover concurrency, the translation layer, loopback proxy, route
provisioning, credential sync, per-account usage, locale parity, and pack
contents.
License
MIT — see LICENSE. Protocol references: SPEC.md.
