Head to head · Agent harnesses · October 2026 research run

Antigravity CLI vs Pi

Pi scores 68.4 (B) on agent readiness against Antigravity CLI's 57.7 (C), and leads in 6 of 7 scored categories. Both do agent harnesses.

Best agent harnesses and coding agents · All 186 harnesses comparisons

Which one, for what

Antigravity CLI C

Best for Developers on Google AI plans or Gemini Enterprise who want a terminal agent with a sandbox on by default and access to several model families, depending on plan.

Also in its favour

  • No incidents deducted, where Pi loses 4 points for them

Watch for

Closed source. The repository holds the README, changelog and examples, with no source and no licence file

Pi B

Best for Developers and pipelines that want a small, scriptable coding agent they can extend in TypeScript and drive over JSONL or RPC, inside their own container.

Ahead on

  • Reliability, 75 against 43
  • Schema & documentation, 84 against 78
  • Security & auth, 61 against 53
  • Payments & pricing, 60 against 30
  • Maintenance & community, 87 against 68
  • Transparency & trust, 64 against 54

Also in its favour

  • No key needed to call it
  • Free to start without a card
  • Open source

Watch for

No permission system or sandbox. Tool calls run with the user's rights and without an approval prompt

Score by category

CategoryWeight this runAntigravity CLIPiEdge
Reliability16%204375Pi +32
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27884Pi +6
Agent ergonomics13%16.27876Antigravity CLI +2
Security & auth14%17.55361Pi +8
Payments & pricing10%12.53060Pi +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.86887Pi +19
Transparency & trust7%8.85464Pi +10
Negative events≤150-4
TotalC 57.7/100B 68.4/100

Facts side by side

FactAntigravity CLIPi
KindAgent harnessAgent harness
VendorGoogleEarendil
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyNone
PricingFreemiumFree
x402nono
LicenceProprietary. The repository holds the README, changelog and examples, with no source and no licence file. Use is under the Google Antigravity Additional Terms of Service, the Google Terms of Service and the Privacy PolicyMIT
Read-only variant documentednono
llms.txtyesno
Last release2026-10-082026-10-07
Terms last updatedno document linked
Privacy policy last updated2026-10-01no document linked
Customer content may train modelsyes
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularitynone113k stars, 5.2M npm/wk

Verdicts

Antigravity CLI

Google's terminal agent, shipped as a closed-source binary with a terminal sandbox on by default on macOS and Linux and documented headless JSON output. Interactions are used to improve Google products unless users opt out, and a headless run exits 0 when a tool is denied.

Pi

Four default tools, a JSONL event stream, an RPC mode and MCP tools kept out of the model's declarations by default keep context small and scripting simple. Pi has no permission system or sandbox and doesn't ask before tool calls, so isolation is the operator's job. Version 1.0.0 is dated 1 October 2026.

Before you call either

Antigravity CLI

  1. Read the status field from --output-format json and read stderr too. A tool refused for lack of approval still exits 0
  2. Pre-approve each shell command and tool a headless run needs with action(target) rules under permissions.allow in ~/.gemini/antigravity-cli/settings.json, because headless runs cannot ask
  3. Export GEMINI_API_KEY after setting modelProvider to gemini. The CLI won't start when the key is missing, and setting the variable alone has no effect
  4. Turn off Enable Telemetry in the Account settings before running on private repositories if Interactions should not be used for product improvement
  5. Set --print-timeout explicitly. The docs give a five-minute default, while agy --help shows 0s

Pi

  1. Run Pi inside a container or VM for unattended work. It has no sandbox and doesn't ask before running shell commands
  2. Use pi --mode json and wait for agent_settled. A failed response doesn't set a nonzero exit code in JSON mode
  3. Split the JSONL stream on LF only. Node's readline also splits on U+2028 and U+2029, which are valid inside JSON strings
  4. Pass --no-approve or --approve in scripts to make the project trust decision explicit
  5. Set PI_TELEMETRY=0 and PI_SKIP_VERSION_CHECK=1, or PI_OFFLINE=1, to stop the default requests to pi.dev

Questions

Which is better for AI agents, Antigravity CLI or Pi?

Pi scores 68.4 (B) on agent readiness against Antigravity CLI's 57.7 (C), and leads in 6 of 7 scored categories.

Are Antigravity CLI and Pi open source?

No open-source release is listed for Antigravity CLI. Pi is open source (MIT).

Other comparisons with Antigravity CLI or Pi

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