API Testing
Providers using this tag (50)
Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.
Exemplar 1 Complete, well-documented, and agent-ready
Developing 11 Usable, with meaningful gaps to close
Thin 14 Limited public surface area
Emerging 15 Early or largely undocumented
Minimal 4 Almost no public developer surface
APIs with this tag (32)
Ranked by the provider's API Evangelist rating — the Kin Score is scored per provider, not per API, so every API of a provider shares its band. How the rating works →
Exemplar 1 Complete, well-documented, and agent-ready
Strong 3 Solid coverage with minor gaps
PactFlowPactFlow is SmartBear's contract testing platform that ensures API changes do not break consumer applicatio...ReadyAPIReadyAPI is SmartBear's API quality platform for functional, security, and performance testing. It supports...Keploy MCP ServerHosted, remote Model Context Protocol server (streamable HTTP, bearer kep_ PAT auth) at https://api.keploy....
Developing 7 Usable, with meaningful gaps to close
Bruno API ClientThe core open-source, git-native desktop API client (a lightweight Postman/Insomnia alternative). Compose a...Bruno API ClientBruno is an open-source API client for exploring and testing REST, GraphQL, and gRPC APIs. Collections are ...Bruno CLI (bru)The @usebruno/cli command-line runner (invoked as bru, installed via npm install -g @usebruno/cli) executes...Spec Scoring APIPublic, no-auth REST API for scoring OpenAPI documents. GET /api/review/checks returns the full set of chec...Fiddler EverywhereFiddler Everywhere is a cross-platform web debugging proxy for macOS, Windows, and Linux. It captures HTTP ...Assertible APIAssertible's public programmatic surface, used to drive test runs from a CI/CD pipeline. It consists of two...Testkit (YAML API Testing DSL)MIT-licensed Rust testing tool by the APItoolkit/Monoscope team that uses a simplified YAML DSL for definin...
Thin 7 Limited public surface area
Traceable API Security PlatformTraceable provides an intelligent API security platform offering API discovery, threat detection and protec...Speedscale PlatformSpeedscale captures production API traffic and replays it in lower environments for load testing, regressio...SchemathesisSchemathesis is a property-based API testing tool that automatically generates test cases from OpenAPI and ...HoppscotchHoppscotch is a lightweight open-source browser-based API client supporting REST, GraphQL, WebSockets, SSE,...REST AssuredREST Assured is a Java DSL library for testing and validating RESTful APIs using a fluent, BDD-style syntax...GoReplayGoReplay captures live HTTP traffic with libpcap and replays it against a test target, letting teams valida...REST ClientREST Client is a Visual Studio Code extension for sending HTTP requests and viewing responses directly with...
Emerging 13 Early or largely undocumented
Thunder ClientThunder Client is the flagship VS Code REST API client extension offering a lightweight GUI for sending HTT...Thunder Client CLIThe Thunder Client CLI (@thunderclient/cli) is a Node.js command-line tool for running Thunder Client reque...SuperTestSuperTest is a Node.js library for testing HTTP servers by providing a high-level abstraction for HTTP asse...RestfoxRestfox is a lightweight, offline-first web HTTP client for testing REST APIs, similar to Postman but brows...Broadcom BlazeMeterContinuous testing platform for API, web, mobile, and performance testing. Exposes a REST API for orchestra...cURL Command Line ToolThe curl command-line tool transfers data to or from a server using URL syntax, supporting protocols includ...DreddDredd is a language-agnostic command-line tool for validating an API description document against a backend...Runscope API Monitoring APIREST API for the Runscope (now BlazeMeter API Monitoring) platform. Manages buckets, API tests, environment...Step CIStep CI is an open source API Quality Assurance framework that is language-agnostic and configured using YA...Arga APIPublic REST API for Arga's testing infrastructure — provision digital twins, deploy branches/PRs into sandb...Mitmproxymitmproxy is a free and open source interactive HTTPS proxy for intercepting, inspecting, modifying, and re...Noname Active TestingNoname Active Testing enables organizations to test APIs for vulnerabilities and misconfigurations before t...Noname API Security PlatformThe Noname API Security Platform provides comprehensive API security through discovery, posture management,...
Minimal 1 Almost no public developer surface
Companies reaching this through an API (5)
These companies publish an API, specification or operation carrying “API Testing” but do not classify their business under it. Listed unranked and kept out of the count above, because one tagged operation is not a statement about what a company does.
Score breakdown
Frequency
51.9
log-scaled weighted occurrences
Breadth
1.3
spread across providers
Quality lift
38.5
mean composite of providers using it
Cohesion
10.0
strength of nearest seed neighbor
Where this tag sits
Related tags
API Client 8 co-occurrences
API Design 10 co-occurrences
Performance Testing 7 co-occurrences
API Monitoring 6 co-occurrences
Contract Testing 6 co-occurrences
Functional Testing 5 co-occurrences
CI/CD 18 co-occurrences
HTTP Client 6 co-occurrences
Where this tag comes from
Provider tag50
Api tag33
Cohort brief
Auto-generatedThe 49 providers in the APIs.io catalog tagged API Testing, scored on the Kin Score. Every figure below is computed from the catalog — nothing here is written.
Providers
49
of 50 in the catalog
Mean Kin Score
32.1
+9.2 vs catalog 22.9
Mean Agent Readiness
15.1
+3.2 vs catalog 11.9
Spread
6.8–79.6
median 31.2 · σ 15.9
How the 49 split by band
Exemplar 1Strong 3Developing 12Thin 15Emerging 15Minimal 3
Facet averages, against the whole catalog
| Facet | This cohort | Catalog | Difference | Scored |
|---|---|---|---|---|
| Developer Ergonomics | 33.9 | 23.2 | +10.7 | 49 |
| Operational Transparency | 23.9 | 13.7 | +10.2 | 49 |
| Contract Quality | 26.6 | 17.6 | +9 | 49 |
| Contract Governance | 14.1 | 6.3 | +7.8 | 49 |
| Access Clarity | 34.2 | 26.5 | +7.7 | 49 |
| Discoverability | 62.7 | 58.1 | +4.6 | 49 |
A facet is averaged over the members that carry it, not over the whole cohort — the “Scored” column is that count. Averaging an absent facet as zero would score our own coverage gaps as the providers’ posture.
What this cohort publishes
| Artifact | This cohort | Catalog | Difference |
|---|---|---|---|
| MCP server (any) | 24% | 14% | +10 |
| MCP server (first-party) | 16% | 12% | +4 |
| Agent Skills | 0% | 0% | 0 |
| OAuth scopes | 6% | 11% | -5 |
| Security | 98% | 98% | 0 |
| Arazzo workflows | 6% | 2% | +4 |
| Governance rules | 43% | 14% | +29 |
mcp_pct counts any mcp/ artifact including ones API Evangelist derived from the provider OpenAPI; mcp_first_party_pct counts only servers the provider publishes. Prefer the latter.
Top by Kin Score
Top by Agent Readiness
- 1 Postman 54.9
- 2 Routebase 52.9
- 3 Elva 44.8
- 4 Assertible 34.7
- 5 Keploy 34.6
- 6 Testmail 30.6
- 7 Agent Diff 30.6
- 8 Ressl 29.9
- 9 Archal 28.8
- 10 Traceable 28.6
All 50 members of this roster resolve to a provider in the
catalog; 49 carry a score (98%).
The figures above describe the scored members only.
Coverage caveat. 26 of 49 scored members had under half their catalog-attributable points satisfied at all (catalog_earned / catalog_max < 0.5). They are INCLUDED in the mean above. A large share here means the cohort mean is partly a measurement of how far our enrichment reached, not only of how these providers publish.Generated from the catalog build of 5 October 2026, across 29093 providers, using the same computation served by the APIs.io cohort API. Briefs are published for rosters of 5 or more scored providers; below that a distribution is not meaningful.
Coverage caveat. 26 of 49 scored members had under half their catalog-attributable points satisfied at all (catalog_earned / catalog_max < 0.5). They are INCLUDED in the mean above. A large share here means the cohort mean is partly a measurement of how far our enrichment reached, not only of how these providers publish.Generated from the catalog build of 5 October 2026, across 29093 providers, using the same computation served by the APIs.io cohort API. Briefs are published for rosters of 5 or more scored providers; below that a distribution is not meaningful.
Work with this as data
Every tag here is available over the APIs.io API and to AI agents over MCP.