Mailosaur
Mailosaur is an email and SMS testing platform for developers and QA teams. It provides a REST API for creating test inboxes, capturing and retrieving messages, running assertions, performing deliverability analysis, and integrating email and SMS testing into CI/CD pipelines. The platform supports authentication testing (TOTP/2FA), spam analysis, SPF/DKIM/DMARC validation, and connects via SMTP, POP3, and IMAP protocols.
Mailosaur publishes 7 API contracts indexed on the APIs.io network, including Analysis API, Devices API, Files API, and 4 more. Tagged areas include Email Testing, SMS Testing, Developer Tools, QA Automation, and CI/CD.
The Mailosaur catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.
Mailosaur’s developer surface includes authentication, documentation, engineering blog, pricing, CLI, code examples, API reference, and 41 more developer resources.
What this lets a business do 1
Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →
What people ask Mailosaur 7
The questions people put to an LLM, and the jobs they hand an agent, that Mailosaur's APIs answer — each one linked to the operation that does it. Generated by API Evangelist
Kin Score
Standards implemented 1
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.
APIs 7
Individual APIs this provider publishes, each with its own machine-readable definition.
Mailosaur Analysis API
Operations for analyzing the content and deliverability of an email, including SpamAssassin scoring and per-provider deliverability reports.
Mailosaur Devices API
Operations for managing virtual security devices and retrieving their current one-time passwords (OTPs), used to automate testing of app-based multi-factor authentication.
Mailosaur Files API
Operations for downloading the raw content associated with a message — file attachments, the full EML source of an email, and rendered email previews.
Mailosaur Messages API
Operations for finding, retrieving, creating, forwarding, replying to, and deleting the email and SMS messages received by your Mailosaur inboxes.
Mailosaur Previews API
Operations for discovering the email clients available for generating email previews (screenshots of an email rendered in real clients).
Mailosaur Servers API
Operations for creating and managing your Mailosaur inboxes (servers). Inboxes group your tests together, each with its own domain and SMTP/POP3/IMAP credentials.
Mailosaur Usage API
Operations for inspecting your account's usage limits and recent transactional usage. These endpoints require authentication with an account-level API key.
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Open Collections 7
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
API Collection
OPEN COLLECTIONMailosaur Analysis API
OPEN COLLECTIONMailosaur Analysis Devices API
OPEN COLLECTIONMailosaur Analysis Files API
OPEN COLLECTIONMailosaur Analysis Messages API
OPEN COLLECTIONMailosaur Analysis Servers API
OPEN COLLECTIONMailosaur Analysis Usage API
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Pricing Plans 1
Published pricing tiers and plan structures.
Rate Limits 1
Documented rate limits and quota policies.
Mailosaur Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals for API financial operations.
Mailosaur Finops
FINOPSSemantic Vocabularies 1
JSON-LD contexts and semantic vocabularies used across these APIs.
Mailosaur Context
JSON-LDSpectral Rules 1
Spectral governance rulesets for linting and validating these APIs.
Mailosaur — jsonschema rules
SPECTRALOpenAPI Overlays 14
Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.
Mailosaur Analysis Api Overlay
GENERATEDMailosaur Analysis Api Phrasing Overlay
GENERATEDMailosaur Devices Api Overlay
GENERATEDMailosaur Devices Api Phrasing Overlay
GENERATEDMailosaur Files Api Overlay
GENERATEDMailosaur Files Api Phrasing Overlay
GENERATEDMailosaur Messages Api Overlay
GENERATEDMailosaur Messages Api Phrasing Overlay
GENERATEDMailosaur Previews Api Overlay
GENERATEDMailosaur Previews Api Phrasing Overlay
GENERATEDMailosaur Servers Api Overlay
GENERATEDMailosaur Servers Api Phrasing Overlay
GENERATEDMailosaur Usage Api Overlay
GENERATEDMailosaur Usage Api Phrasing Overlay
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JSON Schema 3
Standalone JSON Schema definitions for this provider's data models.
Examples 4
Example request and response payloads for these APIs.
Mailosaur Get Otp Example
EXAMPLESecurity Posture 3
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 4
Portal, sign-up, and the first successful call
Documentation 5
Reference material describing how the API behaves
Agent Surfaces 4
MCP servers, agent skills, and machine-readable catalogs
Design & Contract 8
Pagination, idempotency, versioning, errors, and events
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Build 9
SDKs, sample code, and the tooling you integrate with
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Access & Security 4
Authentication, authorization, and security posture
Operate 3
Status, limits, changes, and where to get help
Commercial 6
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API
Other 2
Properties that don't map to a standard resource type
Source (apis.yml)
Work with this as data
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