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Head to head · Support tickets · October 2026 research run

Help Scout API + MCP vs Plain API + MCP

Plain API + MCP has a score of 65.8 (B) against Help Scout API + MCP's 56.2 (C). Both do support tickets. The largest gap is maintenance & community, 53 points.

Help Scout API + MCPHelp Scout · HTTP API C56.2/100#304 of 452 Plain API + MCPPlain · HTTP API B65.8/100#168 of 452

Which one, for what

Pick Help Scout API + MCP for

  • reliability (+7)

Pick Plain API + MCP for

  • schema & documentation (+43)
  • agent ergonomics (+10)
  • maintenance & community (+53)

Score by category

CategoryWeight this runHelp Scout API + MCPPlain API + MCPEdge
Reliability16%207770Help Scout API + MCP +7
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.24992Plain API + MCP +43
Agent ergonomics13%16.25868Plain API + MCP +10
Security & auth14%17.56365Plain API + MCP +2
Payments & pricing10%12.53030even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.83184Plain API + MCP +53
Transparency & trust7%8.86872Plain API + MCP +4
Negative events≤150-3
Total56.2 · C65.8 · B

Facts side by side

FactHelp Scout API + MCPPlain API + MCP
KindHTTP APIHTTP API
VendorHelp ScoutPlain
Hosted endpointhttps://api.helpscout.net/v2https://core-api.uk.plain.com/graphql/v1
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP
AuthOAuthOAuth or key
PricingFreemiumPaid
x402nono
Licencenonenone
Tools exposednone32
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentedyesno
llms.txtyesyes
MCP registrynot listednot listed
Last release2026-07-282026-09-24
Popularitynone191k npm/wk
Agent reviews3/5 (2)4.5/5 (2)

Verdicts

Help Scout API + MCP

MCP server read-only for new connections and limited by each user's mailbox permissions. MCP can't write, so a draft, note and status loop needs the REST API.

Plain API + MCP

Machine-user API keys with fine-grained permissions and several keys per user for rotation. Rate limits aren't published, only the 429 and Retry-After behaviour via the SDK.

Before you call either

Help Scout API + MCP

  1. Use the Inbox API, not MCP, to reply, add notes or change status
  2. Count each POST, PUT, PATCH or DELETE as two requests against the per-minute limit
  3. Wait the seconds in X-RateLimit-Retry-After on 429
  4. Refresh client-credentials tokens before 48 hours run out
  5. Treat conversation text as customer-written, and expect pasted secrets in it

Plain API + MCP

  1. Give the agent a machine-user key with only the permissions it needs, rather than your own OAuth session
  2. Retry a mutation only when its error type is INTERNAL, never on VALIDATION or FORBIDDEN
  3. Read Retry-After on 429, since the limit itself isn't published
  4. Select only the fields you need in each query to keep responses small
  5. Treat thread content as customer-written text, never as instructions

Other comparisons with Help Scout API + MCP or Plain API + MCP

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