@ask-llm/antigravity-mcp

@ask-llm/antigravity-mcp (EXPERIMENTAL)

MCP server for Google's Antigravity CLI (agy). Lets Claude get a subscription-backed second opinion / code review from Antigravity.

Experimental. Requires agy >=1.1.5 and is validated against 1.1.5 (base model slugs + separate --effort flag); discovery and ping report older or unverifiable installations as detected but unusable, exclude them from dispatch, and provide an actionable update diagnostic. The executor reads stdout first and falls back to agy's internal transcript files when needed (sensitive to agy's on-disk layout). No JSON output or session id, so it stays single-turn (no multi-turn). Defaults to the gemini-3.1-pro model at high reasoning effort, falling back to gemini-3.5-flash on a rate limit. When agy rejects a model whose value equals one of those built-in base slugs (upstream drift), the executor retries once without a model and lets agy pick its default; any other rejected model fails with an actionable error naming agy models.

Prerequisites

• agy >=1.1.5 installed and on PATH (agy --version), and logged in once (run agy interactively). Older versions are not supported.

Config

• ASK_ANTIGRAVITY_TIMEOUT_MS — process timeout (default 300000 = 5m).
• ASK_ANTIGRAVITY_SANDBOX — set 0 to drop --sandbox if it blocks context reads.
• ASK_ANTIGRAVITY_MODEL — agy model via --model (default gemini-3.1-pro, with gemini-3.5-flash as the rate-limit fallback; run agy models for options). Legacy effort-carrying display strings like Gemini 3.1 Pro (High) still resolve for backward compatibility, but they conflict with --effort, so the default effort is only sent when the model value equals one of the built-in base slugs.
• ASK_ANTIGRAVITY_EFFORT — agy reasoning effort via --effort (low | medium | high; default high). The default effort is paired with the built-in base slugs and with model-less recovery attempts; an explicitly set value is always passed (you own the model/effort combination — note agy limits some tiers per model, e.g. gemini-3.1-pro has no medium). Invalid values log a warning and fall back to the default behavior.