Stoplight is a collaborative, design-first API platform providing a visual editor for OpenAPI specifications, interactive hosted documentation, automatic mock servers, API style guides and governance, and open-source tools including Prism (mock server), Spectral (JSON/YAML linter), and Elements (documentation components). Acquired by SmartBear in 2023, Stoplight is now positioned within SmartBear's API Hub solution group alongside SwaggerHub, with Spectral, Prism, and Elements progressively integrated into the unified API Hub experience. The platform supports OpenAPI v3.1, v3.0, v2.0, Arazzo v1.0, and AsyncAPI v2.x, with integrations for GitHub, GitLab, Bitbucket, and Azure DevOps. The Stoplight status page now redirects to stoplight.status.smartbear.com, confirming the operational consolidation under SmartBear.
Stoplight publishes 7 APIs on the APIs.io network, including Versions API, and 6 more. Tagged areas include API Design, API Documentation, API Governance, AsyncAPI, and Design-First.
The Stoplight catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.
Stoplight’s developer surface includes developer portal, documentation, pricing, engineering blog, support, signup flow, getting-started guide, and 54 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
Horizontal (data, software, accessibility, platform) regime, so
Regulatory Posture carries 15 points of the composite.
If this regime is wrong for your business, say so on your
provider repo — the
applicability map is public and we will correct it.
Open Source Surface applies to this provider. This product is open source and we
read its repository directly, so Open Source Surface carries
10 points of the composite. It is scored from what the repository actually
publishes — a security policy, a contribution guide, a release history, a code of conduct — read live from the
provider rather than inferred from our own catalog pointers.
This facet adds; nothing was taken away to make room for it. An open-source project is not excused from
the commercial facets, because exemption would strip it of the points it does earn.
If we have the wrong repository, or this product is not open source, say so on your
provider repo and we
will drop the facet rather than have you publish against it.
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.
The six quality facets above are damped to 65 points between them,
because both conditional facets apply and carry
35 points together. That is why each facet's contribution is shown against a damped
maximum: raising a quality facet moves the composite by 65% of its nominal
weight, not 100%. The full arithmetic is at apis.io/rating/.
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/stoplight: 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 →
Stoplight is an area vendor: providers adopt it to run part of their developer surface. This is the Kin Score checks its features can move for a provider that adopts it, what each one really earns, and what it earns nothing for.
documentationcapability map9 features checked 2026-09-25 · rubric v0.22.0
Stoplight’s distinctive lift is Spectral: its OpenAPI ruleset flags missing info contact and description, operation descriptions, tags, operationIds, success responses and servers, which is a real route into Contract Quality, and a published Spectral ruleset is exactly what rules_present reads. The hosted docs add the usual reference, try-it and quick-start pointers. Every one of those needs the provider to act (fix the flagged spec, publish the ruleset, declare the pointers), and Stoplight contributes nothing to Agent Readiness beyond a code-sample link fallback; no llms.txt, MCP server, skills or agent card are offered.
Agent Readiness1.8 of 139 pts
Contract Governance10.0 of 33 pts
Contract Quality30.0 of 211 pts
Developer Ergonomics15.0 of 42 pts
Check
Earns
Through
Request/Response Examplespartial Agent ReadinessThe dimension reads examples inside the OpenAPI first; generated request samples reach only the Examples / Code Samples link fallback.
Publishes a ruleset Contract GovernanceSpectral is the format the check is written for; catalog-wide only 0.65% of providers earn it outright, most others carry an API Evangelist-derived ruleset graded partial.
Success responses definedsaturated Contract Quality91% of providers with a contract, docs and a reference already earn this; the vendor cannot move it for most of its buyers.
Documentationsaturated Developer Ergonomics95% of providers with a contract, docs and a reference already earn this; the vendor cannot move it for most of its buyers.
Operations are taggedsaturated Contract Quality92% of providers with a contract, docs and a reference already earn this; the vendor cannot move it for most of its buyers.
Unique operationIdssaturated Contract Quality92% of providers with a contract, docs and a reference already earn this; the vendor cannot move it for most of its buyers.
Enumerates OAuth scopessaturated Contract QualityOnly if the API already uses OAuth scopes; a style-guide rule can demand scope lists, it cannot design the authorization model.
API referencesaturated Developer Ergonomics94% of providers with a contract, docs and a reference already earn this; the vendor cannot move it for most of its buyers.
Across 8977 providers that publish a contract, adopting Stoplight would move 8977. Median lift: composite +7.4 (90th percentile +10.0), agent readiness +1.2 (+1.3). Conditional rows excluded.
What Stoplight ships that earns nothing (3)
Hosted API documentation and developer hub — No Stoplight page claims llms.txt generation, and Stoplight’s own docs host returns 404 for /llms.txt.
Prism mock server (open source) — Prism serves the examples a document already has (or generates them dynamically); it writes none into the contract.
Platform style guides — A style guide kept inside the Platform is private; nothing is counted until the provider publishes the ruleset, and then the rules_present row applies.
A model, not a score. Adopting this vendor changes a provider's Kin Score only when the provider publishes the resulting artifacts on its own surface; nothing here writes a score, and no sponsorship or partnership can. The rating is not for sale → · Full vendor facets artifact
Stoplight Platform is a SaaS collaborative API design and documentation management tool providing a visual editor for OpenAPI specifications, interactive hosted documentation, a...
Prism is an open-source HTTP mock and proxy server that turns any OpenAPI v2/v3 or Postman Collection file into a realistic API server with mocking, transformations, and validat...
Spectral is an open-source JSON and YAML linter for creating automated API style guides and governance rulesets. Provides built-in support for OpenAPI v3.1, v3.0, and v2.0, Araz...
Elements is an open-source toolkit for building beautiful, interactive API documentation from OpenAPI specifications using embeddable React or Web Components. Provides highly cu...
Stoplight Studio is the visual API design and technical writing editor included in the Stoplight Platform. Provides a form-based editor for creating and editing OpenAPI v2 and v...
The Stoplight CLI enables programmatic linting of API descriptions and pushing analysis results to the Stoplight Platform from CI/CD pipelines. Supports analyzing local projects...
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Kin Score
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