sendmux-ai

Sendmux AI provides an Email API designed for AI agents, offering unified endpoints to send and receive emails, manage calendars, and store files. The platform includes inboxes for agents, developer tools, SDKs, and a CLI, enabling seamless integration of email capabilities into AI-driven applications across various use cases such as customer support, sales outreach, and scheduling.

sendmux-ai publishes 11 API contracts indexed on the APIs.io network, including Billing API, Connection API, Domain Filters API, and 8 more. Tagged areas include Company, Email, AI, Agents, and Integration.

The sendmux-ai catalog on APIs.io includes 1 event-driven AsyncAPI specification, 1 JSON-LD context, and 1 Spectral governance ruleset.

sendmux-ai’s developer surface includes CLI, authentication, changelog, documentation, API reference, getting-started guide, support, and 31 more developer resources.

🌐 Visit website📡 Profile data on GitHub
72.8/100 exemplar Agent 77/100 agent native Full breakdown ↓
scored 2026-10-31 · rubric v0.25.0 · Show this score on your site →
1 published contract 5 Agent Skills
CompanyEmailAIAgentsIntegration

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-10-31 · rubric v0.25.0
Composite quality — 72.8/100 · exemplar
Contract Quality 14.6 / 21
Developer Ergonomics 14.0 / 17
Access Clarity 12.4 / 17
Operational Transparency 4.9 / 11
Contract Governance 8.1 / 10
Discoverability 5.6 / 9
Regulatory Posture 4.8 / 15
Agent readiness — 77/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
Documented Reversibility 0 / 6
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 9 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 4 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 8 / 8
Dry-Run / Simulate Mode 0 / 4
Delegated User Identity 6 / 6
Protected Resource Metadata 5 / 5
Registration Without a Human 6 / 6
Agentic Commerce Well-Known Document 0 / 5
Pagination 5 / 5
Distinct Operations 3 / 3
Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
Show this score on your site. Kin Score badge preview for sendmux-ai It updates itself when the score changes. Paste this where you link to your API docs: 
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Raise your score.
Agent readiness — checks not met, largest first (exact, from this profile):
  • Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too
  • Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's
  • Dry-Run / Simulate Mode +4 pts — OpenAPI: destructive operations expose a dry_run / simulate / preview / validate_only parameter
  • Consent & Bot Identity +3 pts — common[].type includes AIPREF, ContentSignal, WebBotAuth, or HTTPMessageSignatures
Kin Score — facets with the most composite points still available (weight × headroom):
Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/sendmux-ai/apis.yml: open an issue on github.com/api-evangelist/sendmux-ai to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 11

Individual APIs this provider publishes, each with its own machine-readable definition.

sendmux-ai Billing API

The Billing API from sendmux-ai — 3 operation(s) for billing.

sendmux-ai Connection API

The Connection API from sendmux-ai — 1 operation(s) for connection.

sendmux-ai Domain Filters API

The Domain Filters API from sendmux-ai — 1 operation(s) for domain filters.

sendmux-ai Domains API

The Domains API from sendmux-ai — 4 operation(s) for domains.

sendmux-ai Emails API

The Emails API from sendmux-ai — 3 operation(s) for emails.

sendmux-ai Inboxes API

The Inboxes API from sendmux-ai — 2 operation(s) for inboxes.

sendmux-ai Mailbox API

The Mailbox API API from sendmux-ai — 48 operation(s) for mailbox api.

sendmux-ai Mailbox Filters API

The Mailbox Filters API from sendmux-ai — 1 operation(s) for mailbox filters.

sendmux-ai Mailboxes API

The Mailboxes API from sendmux-ai — 9 operation(s) for mailboxes.

sendmux-ai Sending accounts API

The Sending accounts API from sendmux-ai — 11 operation(s) for sending accounts.

sendmux-ai Webhooks API

The Webhooks API from sendmux-ai — 6 operation(s) for webhooks.

Scroll for all 11

Agent Skills 5

Packaged agent skills for driving this provider's APIs from an AI assistant.

sendmux-ai-create-and-activate-sending-account

AGENT SKILL

sendmux-ai-create-and-send-draft-with-attachment

AGENT SKILL

sendmux-ai-create-mailbox

AGENT SKILL

sendmux-ai-manage-domain

AGENT SKILL

sendmux-ai-manage-webhooks

AGENT SKILL

Pricing Plans 1

Published pricing tiers and plan structures.

Sendmux Ai Plans Pricing

3 plans

PLANS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Sendmux Ai Webhooks

ASYNCAPI

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Sendmux Ai Context

120 classes · 319 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

sendmux-ai API Rules

14 rules · 10 errors 3 warnings 1 info

SPECTRAL

JSON Schema 6

Standalone JSON Schema definitions for this provider's data models.

CreateCalendarEventBody

7 properties

JSON SCHEMA

CreateMailboxDraft

12 properties

JSON SCHEMA

ProviderCreateBody

14 properties

JSON SCHEMA

ProviderUpdateBody

14 properties

JSON SCHEMA

SendMailboxMessageBody

10 properties

JSON SCHEMA

UpdateMailboxDraft

11 properties

JSON SCHEMA

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Sendmux Ai Authentication

2 schemes

SECURITY

Sendmux Ai Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Sendmux Ai Scopes

52 scopes · authorizationCode

52 scopes

SCOPES

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Sendmux Ai Agentic Access

119 operations · 50 acting · 2 human-in-the-loop

119 operations · 50 acting

AGENTIC

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess
 AgentSkill
AgentSkill
 LLMsTxt
LLMsTxt
 WellKnown
WellKnown

Design & Contract 9

Pagination, idempotency, versioning, errors, and events

Spectral
Spectral
 JSONLD
JSONLD
 Vocabulary
Vocabulary
 Webhooks
Webhooks
 DataModel
DataModel
 Idempotency
Idempotency
 Conventions
Conventions
 ErrorCatalog
ErrorCatalog
 Conformance
Conformance

Scroll for all 9

Build 5

SDKs, sample code, and the tooling you integrate with

CLI
CLI
 SDKs
SDKs
 Packages
Packages
 GitHubOrganization
GitHubOrganization
 Postman
Postman

Access & Security 3

Authentication, authorization, and security posture

Authentication
Authentication
 OAuthScopes
OAuthScopes
 DomainSecurity
DomainSecurity

Operate 3

Status, limits, changes, and where to get help

StatusPage
StatusPage
 ChangeLog
ChangeLog
 Support
Support

Commercial 4

Pricing, plans, and the legal terms of use

Plans
Plans
 Pricing
Pricing
 TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Other 3

Properties that don't map to a standard resource type

AgentCard
AgentCard
 Hosts
Hosts
 Vendors
Vendors

Source (apis.yml)

apis.yml Raw ↑ 
aid: sendmux-ai
name: sendmux-ai
image: https://sendmux.ai/og-image.jpg
description: Sendmux AI provides an Email API designed for AI agents, offering unified endpoints to send and receive emails,
  manage calendars, and store files. The platform includes inboxes for agents, developer tools, SDKs, and a CLI, enabling
  seamless integration of email capabilities into AI-driven applications across various use cases such as customer support,
  sales outreach, and scheduling.
url: https://artifacts.apis.io/sendmux-ai/apis.yml
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-10-31 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-10-31'
modified: '2026-10-31'
tags:
- Company
- Email
- AI
- Agents
- Integration
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/sendmux-ai-agentic-access.yml
- type: Plans
  url: plans/sendmux-ai-plans-pricing.yml
- type: Spectral
  url: rules/sendmux-ai-rules.yml
- type: JSONLD
  url: json-ld/sendmux-ai-context.jsonld
- type: Vocabulary
  url: vocabulary/sendmux-ai-vocabulary.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Webhooks
  url: asyncapi/sendmux-ai-webhooks.yml
- type: DataModel
  url: data-model/sendmux-ai-data-model.yml
- type: CLI
  url: cli/sendmux-ai-cli.yml
- type: Idempotency
  url: conventions/sendmux-ai-conventions.yml
- type: Conventions
  url: conventions/sendmux-ai-conventions.yml
- type: Authentication
  url: authentication/sendmux-ai-authentication.yml
- type: ErrorCatalog
  url: errors/sendmux-ai-problem-types.yml
- type: Conformance
  url: conformance/sendmux-ai-conformance.yml
- type: LLMsTxt
  url: llms/sendmux-ai-llms.txt
- type: AgentCard
  url: a2a/sendmux-ai-a2a.yml
- type: WellKnown
  url: well-known/sendmux-ai-well-known.yml
- type: Hosts
  url: hosts/sendmux-ai-hosts.yml
- type: Vendors
  url: vendors/sendmux-ai-vendors.yml
- type: SDKs
  url: packages/sendmux-ai-packages.yml
- type: Packages
  url: packages/sendmux-ai-packages.yml
- type: StatusPage
  url: https://status.sendmux.ai/
- type: ChangeLog
  url: https://sendmux.ai/docs/changelog
- type: DeveloperPortal
  url: https://api.youragent.app/sendmux&quot;</span
- type: OAuthScopes
  url: scopes/sendmux-ai-scopes.yml
- type: DomainSecurity
  url: security/sendmux-ai-domain-security.yml
- type: Website
  url: https://sendmux.ai/
- type: Documentation
  url: https://sendmux.ai/docs
- type: APIReference
  url: https://sendmux.ai/docs/api/introduction
- type: GettingStarted
  url: https://sendmux.ai/docs/getting-started/quickstart
- type: Support
  url: https://sendmux.ai/contact
- type: Blog
  url: https://sendmux.ai/blog/
- type: GitHubOrganization
  url: https://github.com/Sendmux
- type: Pricing
  url: https://sendmux.ai/pricing/
- type: SignUp
  url: https://app.sendmux.ai/sign-up
- type: TermsOfService
  url: https://sendmux.ai/terms/
- type: PrivacyPolicy
  url: https://sendmux.ai/privacy/
- type: Postman
  url: https://sendmux.ai/docs/developer-tools/postman
apis:
- aid: sendmux-ai:sendmux-ai-billing-api
  name: sendmux-ai Billing API
  description: The Billing API from sendmux-ai — 3 operation(s) for billing.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Billing
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-billing-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-connection-api
  name: sendmux-ai Connection API
  description: The Connection API from sendmux-ai — 1 operation(s) for connection.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Connection
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-connection-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-domain-filters-api
  name: sendmux-ai Domain Filters API
  description: The Domain Filters API from sendmux-ai — 1 operation(s) for domain filters.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Domain Filters
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-domain-filters-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-domains-api
  name: sendmux-ai Domains API
  description: The Domains API from sendmux-ai — 4 operation(s) for domains.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Domains
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-domains-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-emails-api
  name: sendmux-ai Emails API
  description: The Emails API from sendmux-ai — 3 operation(s) for emails.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Emails
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-emails-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-inboxes-api
  name: sendmux-ai Inboxes API
  description: The Inboxes API from sendmux-ai — 2 operation(s) for inboxes.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Inboxes
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-inboxes-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-mailbox-api-api
  name: sendmux-ai Mailbox API
  description: The Mailbox API API from sendmux-ai — 48 operation(s) for mailbox api.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Mailbox API
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-mailbox-api-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-mailbox-filters-api
  name: sendmux-ai Mailbox Filters API
  description: The Mailbox Filters API from sendmux-ai — 1 operation(s) for mailbox filters.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Mailbox Filters
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-mailbox-filters-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-mailboxes-api
  name: sendmux-ai Mailboxes API
  description: The Mailboxes API from sendmux-ai — 9 operation(s) for mailboxes.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Mailboxes
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-mailboxes-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-sending-accounts-api
  name: sendmux-ai Sending accounts API
  description: The Sending accounts API from sendmux-ai — 11 operation(s) for sending accounts.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Sending accounts
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-sending-accounts-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
- aid: sendmux-ai:sendmux-ai-webhooks-api
  name: sendmux-ai Webhooks API
  description: The Webhooks API from sendmux-ai — 6 operation(s) for webhooks.
  humanURL: https://sendmux.ai/docs/api/introduction
  baseURL: https://app.sendmux.ai/api/v1
  tags:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/sendmux-ai-webhooks-api-openapi.yml
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-update-mailbox-draft-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-create-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-provider-update-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-send-mailbox-message-body-schema.json
  - type: JSONSchema
    url: json-schema/sendmux-ai-create-calendar-event-body-schema.json
x-enrichment:
  date: '2026-10-31'
  status: enriched
  artifacts_added: 41
  pass: modular-v1
  engine: identity=local,contract=local,surfaces=local,docs=local,regulatory=local

sendmux-ai API — frequently asked questions

Does sendmux-ai have an API?

Yes. APIs.io lists 11 APIs from sendmux-ai, including sendmux-ai Billing API, sendmux-ai Connection API and sendmux-ai Domain Filters API, and 8 more.

Is there an OpenAPI specification for the sendmux-ai API?

Yes. APIs.io indexes 11 OpenAPI specifications for sendmux-ai, each linked for download from this page.

How do I authenticate with the sendmux-ai API?

sendmux-ai documents its authentication (2 schemes). The details are profiled on APIs.io as Sendmux Ai Authentication.

How much does the sendmux-ai API cost?

APIs.io lists 3 pricing plans for sendmux-ai, with each plan's price, limits and inclusions under Pricing Plans on this page.

Is the sendmux-ai API ready for AI agents?

sendmux-ai has a Kin Score of 72.8 out of 100 (exemplar) and an Agent Readiness score of 77.3 (agent-native), scored by API Evangelist on 2026-10-31.

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  • get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
  • get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
  • get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
  • get_provider_ratingPRO — composite, band, trend and facet scores.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools →

Call it yourself

curl for this page
This provider 
curl "https://apis.io/api/v1/providers/sendmux-ai"
All providers 
curl "https://apis.io/api/v1/providers?limit=25"
Every operation they expose 
curl "https://apis.io/api/v1/providers/sendmux-ai/operations?limit=25"
How their score was established 
curl "https://apis.io/api/v1/providers/sendmux-ai/evidence"

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