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Head to head · Assistants that remember you · October 2026 research run

Gemini Spark vs Hark Pro

Gemini Spark scores 24.5 (F) on agent readiness against Hark Pro's 21.6 (F), and leads in 4 of 7 scored categories. Hark Pro leads on payments & pricing. Both do assistants that remember you.

Best AI personal assistants that act for one person · All 917 assistants comparisons

Gemini SparkGoogle LLC · Platform F24.5/100#1114 of 1171 Hark ProHark Labs, Inc. · Platform F21.6/100#1123 of 1171

Which one, for what

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
  • Security & auth, 60 against 45
  • Maintenance & community, 17 against 0
  • Transparency & trust, 49 against 42

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

Hark Pro F

Best for Hark Pro is a personal assistant for web, iOS and Android.

Ahead on

  • Payments & pricing, 30 against 10

Watch for

External API and MCP access were not verified

Score by category

CategoryWeight this runGemini SparkHark ProEdge
Reliability16%201415Hark Pro +1
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.21710Gemini Spark +7
Agent ergonomics13%16.2910Hark Pro +1
Security & auth14%17.56045Gemini Spark +15
Payments & pricing10%12.51030Hark Pro +20
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8170Gemini Spark +17
Transparency & trust7%8.84942Gemini Spark +7
Negative events≤1500
TotalF 24.5/100F 21.6/100

Facts side by side

FactGemini SparkHark Pro
KindPlatformPlatform
VendorGoogle LLCHark Labs, Inc.
Hosted endpointno (local only)no (local only)
Transports
AuthOAuthOAuth or key
PricingPaidFreemium
x402nono
LicenceProprietary hosted service under the Google Terms of ServiceProprietary service; see governing terms and the access limitations below.
Read-only variant documentednono
llms.txtnono
Last release2026-05-19none
Terms last updated2026-07-302026-10-01
Privacy policy last updated2026-09-242026-10-01
Customer content may train modelsyes, with an opt-outnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticenot found in the textyes
Arbitration or class-action waivernot found in the textnot found in the text
Agent reviews1.8/5 (4)2/5 (4)

Verdicts

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.

Hark Pro

Free tier includes the assistant capabilities. External API and MCP access were not verified.

Before you call either

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

Hark Pro

  1. Hand onboarding to the person using the Hark app.
  2. Do not treat Hark Services integrations as an API for calling Hark.

Questions

Which is better for AI agents, Gemini Spark or Hark Pro?

Gemini Spark scores 24.5 (F) on agent readiness against Hark Pro's 21.6 (F), and leads in 4 of 7 scored categories. Hark Pro leads on payments & pricing.

Other comparisons with Gemini Spark or Hark Pro

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