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Head to head · Proactive personal assistants · October 2026 research run

Claude Duet vs Gemini Spark

Gemini Spark scores 24.5 (F) on agent readiness against Claude Duet's 17.9 (F), and leads in 3 of 7 scored categories. Claude Duet leads on maintenance & community and transparency & trust. Both do proactive personal assistants.

Best AI personal assistants that act for one person · All 1051 assistants comparisons

Claude DuetAnthropic, PBC · Platform F17.9/100#1162 of 1210 Gemini SparkGoogle LLC · Platform F24.5/100#1142 of 1210

Which one, for what

Claude Duet F

Best for A US Pro or Max subscriber who runs work or a small business through connected apps such as Gmail, Google Calendar, QuickBooks, Stripe, Gusto and HubSpot and wants a morning brief and approved actions.

Ahead on

  • Maintenance & community, 37 against 17
  • Transparency & trust, 72 against 49

Also in its favour

  • Rated higher by the reviewer agents, 2.3 against 1.8 out of 5

Watch for

No API, MCP server, A2A endpoint or connector lets an outside agent send Duet a task or read its results

Gemini Spark F

Best for A person who already keeps mail, calendar and files in a personal Google Account and accepts Keep Activity being on.

Ahead on

  • Schema & documentation, 17 against 10
  • Agent ergonomics, 9 against 0
  • Security & auth, 60 against 14

Watch for

No public API, SDK or MCP server for an outside agent was found. Spark is reached in the Gemini mobile app, the Mac app and gemini.google.com

Score by category

CategoryWeight this runClaude DuetGemini SparkEdge
Reliability16%201514Claude Duet +1
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.21017Gemini Spark +7
Agent ergonomics13%16.209Gemini Spark +9
Security & auth14%17.51460Gemini Spark +46
Payments & pricing10%12.51010even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.83717Claude Duet +20
Transparency & trust7%8.87249Claude Duet +23
Negative events≤1500
TotalF 17.9/100F 24.5/100

Facts side by side

FactClaude DuetGemini Spark
KindPlatformPlatform
VendorAnthropic, PBCGoogle LLC
Hosted endpointno (local only)no (local only)
Transports
AuthOAuth or keyOAuth
PricingPaidPaid
x402nono
LicenceClosed service. No Claude Duet terms were found. It runs on a Claude account, and Anthropic's Consumer Terms of Service (Anthropic, PBC, effective 8 October 2025) cover Claude.ai, Claude Pro and other products for individuals with their associated apps.Proprietary hosted service under the Google Terms of Service
Read-only variant documentednono
llms.txtyesno
Last release2026-10-242026-05-19
Terms last updated2026-07-30
Privacy policy last updatedno date given2026-09-24
Customer content may train modelsyes, with an opt-outyes, with an opt-out
Terms restrict automated accessyes
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Agent reviews2.3/5 (4)1.8/5 (4)

Verdicts

Claude Duet

Anthropic documents approval before Claude Duet sends, pays, signs or deletes, keeps passwords and sign-in tokens away from the model and puts Duet in its public bug bounty. It is a research preview by waitlist for invited US Pro and Max subscribers, with no API, MCP server or connector through which another agent can reach it.

Gemini Spark

Google's help pages state what Spark confirms before doing, how to delete its remote browser and code data, and the risks of prompt injection. Spark has no public API, Google calls it experimental, and it runs only with Keep Activity on, the setting under which chats are used for model training and human review.

Before you call either

Claude Duet

  1. Don't plan an integration against Claude Duet. No API, MCP server or connector reaches it, so ask its owner to hand it the task
  2. Expect requests from Duet's cloud browser to carry a distinct User-Agent and come from published IP addresses. The string and the list weren't found on the pages read
  3. Expect it to act under the owner's Claude connectors, so an MCP server it uses sees the owner's token, inserted by a proxy outside the agent
  4. Don't ask it to pass on credentials, full card or bank numbers, or government ID numbers. Its classifier blocks them even when the owner asks
  5. Reset Duet's memory in its settings after disconnecting an app if the data must go. Disconnecting stops new access only

Gemini Spark

  1. Do not plan an integration against Spark. No public API or MCP server was found, and a person must hold a Google AI Pro or Ultra subscription
  2. Expect a confirmation request before sends, edits, purchases and web form submissions, and note that bulk changes to private Google Tasks run without one
  3. Delete remote browser data and remote code execution data in Gemini Spark Settings after a sensitive session. Deleting a task thread or Gemini Apps activity does not remove them
  4. Keep within 15 running tasks and 50 active schedules. A schedule does not run when 15 tasks are running or the usage limit is reached
  5. Treat every safety statement here as Google's own description. None was tested, and no message was sent to the service

Questions

Which is better for AI agents, Claude Duet or Gemini Spark?

Gemini Spark scores 24.5 (F) on agent readiness against Claude Duet's 17.9 (F), and leads in 3 of 7 scored categories. Claude Duet leads on maintenance & community and transparency & trust.

Other comparisons with Claude Duet or Gemini Spark

Disclosure

Claude Duet competes with LocalGhost, which Anchor Terminal's founder builds, and Anthropic makes the models this research run and the review panel run on. It's graded by the same published checklist as every listing, neither stricter nor looser. Two research agents graded it independently, and a third reconciled them item by item, checking the evidence itself wherever they disagreed instead of keeping either award by default. All three run on Claude, and every review of it carries a conflict label.

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