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 8 APIs on the APIs.io network, including Account and billing API, Deliverability API, Domains API, and 5 more. Tagged areas include Email API, Transactional Email, Inbound Email, and Deliverability.
SendHQ’s developer surface includes developer console, tooling, support, and 7 more developer resources.
Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it
carries 10 points of the composite. It is scored from the published contracts
themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already
holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in
front of it, and the first time that check is skipped a duplicate record is created.
Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet,
not penalised by it.
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 github.com/api-evangelist/sendhq: open an issue to ask a question, or submit a pull request to add artifacts.
Submit an artifact on GitHub — free →Manage your own listing — the Influence plan, $499/mo →
Resend-compatible REST API for transactional and inbound email, domains, templates, deliverability, and workspace administration. Base URL https://sendhq.cc/api/v1 with Bearer r...
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
created: '2026-08-24'
modified: '2026-08-24'
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
- name: SendHQ REST API
description: Resend-compatible REST API for transactional and inbound email, domains, templates, deliverability, and workspace
administration. Base URL https://sendhq.cc/api/v1 with Bearer re_ API keys.
humanURL: https://sendhq.cc/docs/api-reference
baseURL: https://sendhq.cc/api/v1
tags:
- Email API
- Transactional Email
- Inbound Email
- Email Deliverability
- Developer Tools
- AI Infrastructure
- Agent Ready
tags_raw:
- email API
- transactional email
- inbound email
- email deliverability
- developer tools
- AI infrastructure
- agent-ready
properties:
- type: OpenAPI
url: https://sendhq.cc/openapi.json
- type: Documentation
url: https://sendhq.cc/docs
- type: Documentation
url: https://sendhq.cc/docs/authentication
- type: Documentation
url: https://sendhq.cc/docs/api-reference
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.'
Discovery needs no key. Ratings and market analysis are Pro.
Get an API key
Free tier, no form to fill in. Signing in shares your email address with us — we
store it to create your key and to recognise you if you sign in with another
provider. See our Privacy Policy and
Terms.
Kin Score
How this is scored →