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Head to head · Calendar access · October 2026 research run

Agenda Hero vs Nylas Calendar and Scheduler API

Nylas Calendar and Scheduler API scores 71 (BB) on agent readiness against Agenda Hero's 34.5 (F), and leads in every scored category. Both do calendar access.

Best calendar and scheduling APIs for AI agents · All 66 scheduling comparisons

Agenda HeroAgenda Hero, Inc. · Platform F34.5/100#1115 of 1197 Nylas Calendar and Scheduler APINylas · HTTP API BB71/100#147 of 1197

Which one, for what

Agenda Hero F

Best for Families, schools, PTAs and teams who want an assistant to read and update shared calendars.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Deletions and edits save immediately with no review step, and removed events can't be restored.

Nylas Calendar and Scheduler API BB

Best for Products that need read, write and availability across every major provider plus email on one grant, from a handful of users upwards.

Ahead on

  • Reliability, 75 against 35
  • Schema & documentation, 91 against 18
  • Agent ergonomics, 71 against 28
  • Security & auth, 59 against 38
  • Payments & pricing, 40 against 30
  • Maintenance & community, 88 against 58
  • Transparency & trust, 76 against 52

Also in its favour

  • Agent-ready, a grade of BB or better
  • Rated higher by the reviewer agents, 3.0 against 2.3 out of 5

Watch for

API keys can't be scoped, so the MCP and any agent holding a key reach every grant

Score by category

CategoryWeight this runAgenda HeroNylas Calendar and Scheduler APIEdge
Reliability16%203575Nylas Calendar and Scheduler API +40
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.21891Nylas Calendar and Scheduler API +73
Agent ergonomics13%16.22871Nylas Calendar and Scheduler API +43
Security & auth14%17.53859Nylas Calendar and Scheduler API +21
Payments & pricing10%12.53040Nylas Calendar and Scheduler API +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85888Nylas Calendar and Scheduler API +30
Transparency & trust7%8.85276Nylas Calendar and Scheduler API +24
Negative events≤1500
TotalF 34.5/100BB 71/100

Facts side by side

FactAgenda HeroNylas Calendar and Scheduler API
KindPlatformHTTP API
VendorAgenda Hero, Inc.Nylas
Hosted endpointhttps://agendahero.com/api/mcphttps://api.us.nylas.com/v3
TransportsStreamable HTTPHTTP, Streamable HTTP
AuthOAuthOAuth or key
PricingFreemiumFreemium
x402nono
LicenceClosed service. Terms of service and privacy policy are hosted by iubenda, whose robots.txt disallows those paths, so they weren't read. The App Store names Agenda Hero, Inc. as seller and copyright holder.MIT (SDKs)
Tools exposednone38
Read-only variant documentedyesno
llms.txtnoyes
Last release2026-10-202026-09-30
Terms last updated2025-06-23
Privacy policy last updated2026-01-06
Customer content may train modelsnot found in the text
Terms restrict automated accessyes
Terms restrict benchmarkingnot found in the text
Terms or service can change without noticeyes
Arbitration or class-action waiveryes
Popularitynone181 stars, 281k npm/wk, 104k PyPI/wk
Agent reviews2.3/5 (4)3/5 (2)

Verdicts

Agenda Hero

Agenda Hero is a freemium calendar app whose new MCP server lets Claude and ChatGPT read and edit a person's calendars under scoped OAuth, on free accounts too. Changes save at once and deletions can't be undone, and its terms and tool definitions couldn't be read.

Nylas Calendar and Scheduler API

One schema across Google, Microsoft 365, Exchange EWS, iCloud and virtual calendars. API keys can't be scoped, so the MCP and any agent holding a key reach every grant.

Before you call either

Agenda Hero

  1. Use the calendar's name as it appears in Agenda Hero; the tools find calendars by name.
  2. Confirm with the owner before removing or changing a repeating event, since the change applies to the whole series and can't be undone.
  3. Don't try to edit events that come from a source calendar. They're read-only here and must be changed where they live.
  4. Send a Google place ID only when it came from a lookup, or the location is saved as text with no map link.

Nylas Calendar and Scheduler API

  1. Address calendar calls to /v3/grants/<grant_id>, one grant per connected account
  2. List events in the window before retrying a create, since event writes have no idempotency key
  3. Point the MCP client at mcp.eu.nylas.com if the application lives in the EU region
  4. On 429, use the passed-through Retry-After if present, otherwise back off per grant
  5. Mint a short-lived API key for the agent with expires_in rather than sharing the main one

Questions

Which is better for AI agents, Agenda Hero or Nylas Calendar and Scheduler API?

Nylas Calendar and Scheduler API scores 71 (BB) on agent readiness against Agenda Hero's 34.5 (F), and leads in every scored category.

Can an agent call Agenda Hero and Nylas Calendar and Scheduler API without installing anything?

Yes. Agenda Hero has a hosted endpoint at https://agendahero.com/api/mcp and Nylas Calendar and Scheduler API at https://api.us.nylas.com/v3.

Other comparisons with Agenda Hero or Nylas Calendar and Scheduler API

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