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 7 API contracts indexed on the APIs.io network, including Account and billing API, Deliverability API, Domains API, and 4 more. Tagged areas include Email API, Transactional Email, Inbound Email, and Deliverability.
The SendHQ catalog on APIs.io includes 1 Spectral governance ruleset.
SendHQ’s developer surface includes developer console, tooling, support, and 11 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
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carries 10 points of the composite. It is scored from the published contracts
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Agent readiness — checks not met, largest first (exact, from this profile):
Rate-Limit Signaling+7 pts — OpenAPI responses document X-RateLimit-* / RateLimit headers (verified), else a rate_limits artifact or RateLimits link (documented) Ask about this →
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Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.
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
deliveryModel:
model: saas
open_source: false
commercial: true
callable_host: true
label: Hosted service · you call their endpoint
confidence: high
source:
- openapi
- pricing
generated: '2026-08-28'
method: derived
accessModel:
pricing: unknown
onboarding: unknown
trial: false
try_now: false
public: false
label: Unknown
confidence: low
source: []
generated: '2026-11-13'
method: derived
created: '2026-08-24'
modified: '2026-10-06'
specificationVersion: '0.23'
tags:
- Email API
- Transactional Email
- Inbound Email
- Deliverability
tags_raw:
- email api
- transactional email
- inbound email
- deliverability
apis:
- aid: sendhq:sendhq-account-and-billing-api
name: SendHQ Account and billing API
description: Session-authenticated workspace administration.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Account and billing
properties:
- type: OpenAPI
url: openapi/sendhq-account-and-billing-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
- aid: sendhq:sendhq-deliverability-api
name: SendHQ Deliverability API
description: Inspect events, reputation outcomes, and blocked recipients.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Deliverability
properties:
- type: OpenAPI
url: openapi/sendhq-deliverability-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
- aid: sendhq:sendhq-domains-api
name: SendHQ Domains API
description: Provision sender identities and understand DNS verification state.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Domains
properties:
- type: OpenAPI
url: openapi/sendhq-domains-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
- aid: sendhq:sendhq-drafts-and-attachments-api
name: SendHQ Drafts and attachments API
description: Build composer flows with private attachment storage.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Drafts and attachments
properties:
- type: OpenAPI
url: openapi/sendhq-drafts-and-attachments-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
- aid: sendhq:sendhq-emails-and-threads-api
name: SendHQ Emails and threads API
description: Send, retrieve, search, reply, and inspect delivery events.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Emails and threads
properties:
- type: OpenAPI
url: openapi/sendhq-emails-and-threads-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
- aid: sendhq:sendhq-hosted-templates-api
name: SendHQ Hosted templates API
description: Draft, render, test, version, publish, and send reusable content.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Hosted templates
properties:
- type: OpenAPI
url: openapi/sendhq-hosted-templates-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
- aid: sendhq:sendhq-inbound-email-api
name: SendHQ Inbound email API
description: Create addresses and work with received conversations.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Inbound Email
tags_raw:
- Inbound email
properties:
- type: OpenAPI
url: openapi/sendhq-inbound-email-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:
- url: https://sendhq.cc/feed.xml
type: BlogRSS
- 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
- type: UsageTerms
url: terms/sendhq-terms-of-service.yml
- type: DataProcessing
url: privacy/sendhq-privacy-policy.yml
- type: DataLicense
url: data-license/sendhq-data-license.yml
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.'
SendHQ API — frequently asked questions
Does SendHQ have an API?
Yes. APIs.io lists 7 APIs from SendHQ, including SendHQ Account and billing API, SendHQ Deliverability API and SendHQ Domains API, and 4 more.
Is there an OpenAPI specification for the SendHQ API?
Yes. APIs.io indexes 7 OpenAPI specifications for SendHQ, each linked for download from this page.
How do I authenticate with the SendHQ API?
SendHQ uses bearer-token authentication.
Does SendHQ have an MCP server?
Yes. APIs.io lists 1 MCP server for SendHQ: Remote MCP server at sendhq.cc over HTTP; 4 tools listed.
Is the SendHQ API ready for AI agents?
SendHQ has a Kin Score of 33.1 out of 100 (thin) and an Agent Readiness score of 39.8 (agent-ready), scored by API Evangelist on 2026-11-13.
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