Antigravity Engineer

VS Code extension for Google Antigravity IDE that monitors context window usage, model quotas, and token consumption in real-time by reverse-engineering the internal language server RPC API.

Features

📊 Context Window Monitor

• Prefers server-computed estimatedTokensUsed; falls back to input + cache + output when unavailable
• inputTokens + cacheReadTokens = full cached and uncached sizes
• Visual progress bar showing context fill percentage
• Automatic model detection from apiProvider field
• Best-effort workspace-aware session binding

📈 Model Quota Dashboard

• Per-model quota percentages with reset timers
• Plan name and AI credits from userTier data
• Prompt and Flow credit tracking
• Low/critical quota warnings with configurable thresholds
• Alphabetically sorted for stable UI

🔌 Status Bar

• Compact display: $(pulse) Opus 133K/200K (67%) | 🟢Flash 100% 🔴Opus 0% | 💎10K
• Colored dots: 🟢 >30% | 🟡 1–30% | 🔴 0%
• Configurable: choose which models to show, toggle context/credits
• Rich tooltip with full breakdown
• Click to open dashboard

📋 Sidebar Dashboard

• Connection status with port and PID info
• Context window gauge with progress bar and token breakdown
• Model quota list with percentages and reset timers
• Plan info, AI credits, prompt/flow credits
• Refresh and Show Logs buttons

How It Works

sequenceDiagram
    participant Ext as Extension
    participant PS as Process Table
    participant LS as Language Server
    participant UI as Status Bar + Sidebar

    Ext->>PS: Scan for --csrf_token processes
    PS-->>Ext: PID, CSRF token
    Ext->>PS: Get listening ports (ss -tlnp)
    PS-->>Ext: Port candidates
    Ext->>LS: Probe HTTP POST GetUserStatus
    LS-->>Ext: ServerConnection established

    loop Every 30s (configurable)
        Ext->>LS: GetUserStatus
        LS-->>Ext: Quotas, plan, credits
        Ext->>LS: GetBrowserOpenConversation / GetAllCascadeTrajectories
        LS-->>Ext: Active conversation & Owner LS resolution
        Ext->>Owner_LS: LoadTrajectory (cold fallback)
        Ext->>Owner_LS: GetCascadeTrajectorySteps / GM
        Owner_LS-->>Ext: Authoritative token data
        Ext->>UI: Update display
    end

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All communication is 100% local — no external API calls, no telemetry, no data leaves your machine.

Installation

From .vsix file

# Build and package
npm install
npm run build
npm run package

# Install in Antigravity
antigravity --install-extension antigravity-engineer-0.3.12.vsix

From source (development)

npm install
npm run watch
# Press F5 to launch Extension Development Host

Configuration

Setting	Default	Description
pollingInterval	30	Seconds between polls
lowQuotaThreshold	30	Warning at this % remaining
criticalQuotaThreshold	10	Critical at this % remaining
contextLimitOverrides	{}	Per-model limit overrides
statusBar.showContextWindow	true	Show context window in status bar
statusBar.models	[]	Models to show in status bar (empty = all). Use short names: Opus, Sonnet, Pro, Flash, GPT
statusBar.showCredits	true	Show AI credits in status bar
debugMode	false	Verbose logging

All settings are prefixed with antigravityEngineer.

RPC Endpoints Used

Endpoint	Purpose	Key Fields
GetUserStatus	Quotas, plan, credits	userTier, planStatus, cascadeModelConfigData
GetBrowserOpenConversation	Active chat detection (Pass 1)	cascadeId
GetAllCascadeTrajectories	Active chat fallback (Pass 2)	trajectorySummaries[id].workspaces, stepCount
GetCascadeTrajectory	Trajectory summary, step/GM counts	numTotalSteps, numTotalGM, status
GetCascadeTrajectorySteps	Primary token source	inputTokens, cacheReadTokens, outputTokens, apiProvider
GetCascadeTrajectoryGeneratorMetadata	Fallback token source + estimatedTokensUsed	chatModel.usage, chatModel.contextWindowMetadata
LoadTrajectory	Cold start recovery	cascadeId

Privacy & Security

• ✅ 100% local-first — all communication on 127.0.0.1
• ✅ No telemetry, analytics, or external API calls
• ✅ CSP + nonce on WebView content
• ✅ No credential storage or exfiltration

Architecture

See ARCHITECTURE.md for detailed module breakdown and Mermaid diagrams.

License

MIT