SendHQ

SendHQ is a transactional email API for product teams and AI agents — verified-domain sending, inbound email, hosted templates, drafts and attachments, delivery events, suppressions and workspace-scoped API keys, with a web dashboard at app.sendhq.cc. The public contract is an OpenAPI 3.1 document of 32 paths and 47 operations served from sendhq.cc/api/v1, authenticated with a bearer token or a session cookie. The largest operation groups are hosted templates, drafts and attachments, emails and threads, account and billing, domains, inbound email and deliverability. The company markets the product explicitly at coding agents.

SendHQ publishes 1 API on the APIs.io network. Tagged areas include Email, Transactional Email, Messaging, Deliverability, and Agents.

SendHQ’s developer surface includes developer console, tooling, support, and 7 more developer resources.

30.0/100 thin ▬ flat Agent 27/100 agent aware Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0
1 APIs
EmailTransactional EmailMessagingDeliverabilityAgentsDeveloper Tools

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0
Composite quality — 30.0/100 · thin
Contract Quality 14.3 / 25
Developer Ergonomics 4.3 / 20
Access Clarity 4.2 / 20
Operational Transparency 0.0 / 13
Contract Governance 0.0 / 12
Discoverability 7.2 / 10
Agent readiness — 27/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 9 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Delegated User Identity 0 / 6
Protected Resource Metadata 0 / 5
Registration Without a Human 0 / 6
Agentic Commerce Surface 0 / 5
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/sendhq: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 1

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

SendHQ API

Transactional and inbound email — send, threads, drafts, attachments, hosted templates, domains and DNS verification, deliverability, suppressions, account and billing. 32 paths...

Resources

Get Started 2

Portal, sign-up, and the first successful call

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Build 1

SDKs, sample code, and the tooling you integrate with

Operate 1

Status, limits, changes, and where to get help

Commercial 2

Pricing, plans, and the legal terms of use

Company 1

The organization behind the API

Other 2

Properties that don't map to a standard resource type

Source (apis.yml)

apis.yml Raw ↑
aid: sendhq
name: SendHQ
description: SendHQ is a transactional email API for product teams and AI agents — verified-domain sending, inbound email,
  hosted templates, drafts and attachments, delivery events, suppressions and workspace-scoped API keys, with a web dashboard
  at app.sendhq.cc. The public contract is an OpenAPI 3.1 document of 32 paths and 47 operations served from sendhq.cc/api/v1,
  authenticated with a bearer token or a session cookie. The largest operation groups are hosted templates, drafts and attachments,
  emails and threads, account and billing, domains, inbound email and deliverability. The company markets the product explicitly
  at coding agents.
type: Index
url: https://raw.githubusercontent.com/api-evangelist/sendhq/refs/heads/main/apis.yml
created: '2026-08-24'
modified: '2026-08-24'
specificationVersion: '0.23'
tags:
- Email
- Transactional Email
- Messaging
- Deliverability
- Agents
- Developer Tools
tags_raw:
- email api
- transactional email
- inbound email
- deliverability
apis:
- aid: sendhq:sendhq-api
  name: SendHQ API
  description: Transactional and inbound email — send, threads, drafts, attachments, hosted templates, domains and DNS verification,
    deliverability, suppressions, account and billing. 32 paths, 47 operations, bearer token or session cookie.
  humanURL: https://sendhq.cc/docs/api-reference
  baseURL: https://sendhq.cc/api/v1
  tags:
  - Email
  - Transactional Email
  - Deliverability
  properties:
  - type: OpenAPI
    url: openapi/sendhq-api-openapi.yml
  - type: APIReference
    url: https://sendhq.cc/openapi.json
  - type: Documentation
    url: https://sendhq.cc/docs/api-reference
  - type: GettingStarted
    url: https://sendhq.cc/docs
  - type: Guides
    url: https://sendhq.cc/guides
common:
- type: LLMsTxt
  url: llms/sendhq-llms.txt
- type: Website
  url: https://sendhq.cc/
- type: DeveloperPortal
  url: https://sendhq.cc/docs
- type: Console
  url: https://app.sendhq.cc/
- type: Tools
  url: https://sendhq.cc/tools
- type: Templates
  url: https://sendhq.cc/templates
- type: Glossary
  url: https://sendhq.cc/glossary
- type: TermsOfService
  url: https://sendhq.cc/terms
- type: PrivacyPolicy
  url: https://sendhq.cc/privacy
- type: Support
  url: https://sendhq.cc/contact
maintainers:
- FN: SendHQ
  email: listings@sendhq.cc
  url: https://sendhq.cc/
x-provenance:
  added: '2026-08-24'
  method: searched
  source: https://sendhq.cc/openapi.json
  note: 'Submitted via apis.io/add on 2026-08-24 and auto-published by the gate at rating 51. THE HOST RETURNS A SOFT-200
    AND IT NEARLY COST THEM THE LISTING. sendhq.cc answers any unknown path with an identical 1,212-byte HTML page — same
    SHA for /apis.json, for /for-agents, and for two invented control paths. Both URLs in the submission point at that page,
    so the first pass read the whole site as a catch-all and the record was almost declined on that basis. It was wrong. The
    real pages are real and each a different size: /docs 8,806, /docs/api-reference 8,306, /guides 13,363, plus tools, templates,
    glossary, terms, privacy and contact. The 1,212-byte page is only what a missing path returns. The specification is at
    /openapi.json — 48,625 bytes, OpenAPI 3.1, 32 paths, 47 operations, bearerAuth and sessionCookie — and was found from
    the site''s own API-reference page rather than by guessing. The API is live and correctly gated: /api/v1/emails and /api/v1/domains
    both return 401 JSON. ONE THING FOR THE PROVIDER. SendHQ markets itself as an "AI-agent-ready email API" aimed at Claude,
    Codex, Cursor and OpenClaw, and its llms.txt is real. But /.well-known/agent.json, /.well-known/api-catalog and /.well-known/mcp
    all return the 1,212-byte catch-all rather than a document, so an agent discovering this provider the standard way finds
    nothing. Only the llms.txt and the OpenAPI are genuinely served. Every URL recorded here was fetched and its size checked
    against that catch-all so no artifact in this record is the placeholder page.'

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