OpenSSF

The Open Source Security Foundation (OpenSSF) is a collaborative initiative under the Linux Foundation dedicated to improving the security of open source software. It brings together industry leaders, developers, and security experts to address vulnerabilities, enhance supply chain security, and develop security tools and best practices. OpenSSF stewards a number of projects with public REST APIs, including the OSV (Open Source Vulnerabilities) database, the Scorecard automated security health-check service, and Sigstore signing infrastructure.

OpenSSF publishes 7 API contracts indexed on the APIs.io network, including Projects API, Query API, Querybatch API, and 4 more. Tagged areas include Linux Foundation, Open Source, Security, Supply Chain, and Vulnerabilities.

The OpenSSF catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

OpenSSF’s developer surface includes documentation, developer portal, engineering blog, and 20 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

31.7/100 thin ▬ flat Agent 17/100 agent aware Front door AI 5/6 prominent Heartbeat 100/100 alive Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemium

2 published contracts

Linux Foundation Open Source Security Supply Chain Vulnerabilities

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Cybersecurity Management

BC-620

QueryQuerybatchVulns

POST /v1/query GET /v1/vulns/{id} POST /v1/querybatch

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 31.7/100 · thin

Contract Quality 10.3 / 19

Developer Ergonomics 3.9 / 15

Access Clarity 1.2 / 15

Operational Transparency 3.6 / 10

Contract Governance 0.9 / 9

Discoverability 5.0 / 8

Regulatory Posture 1.6 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 17/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

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.

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 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

Show this score on your site.

It updates itself when the score changes. Paste this where you link to your API docs:

<a href="https://apis.io/providers/openssf/"><img src="https://apis.io/badge/openssf/card.svg" alt="OpenSSF on APIs.io — Kin Score by API Evangelist"></a>

Other styles, a README pill and a shields.io endpoint are on the badge page.

Raise your score.

Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Machine-Readable Auth +10 pts — a served openid-configuration/oauth-authorization-server carrying `issuer` (served), else the securitySchemes class in the provider OpenAPIs — bound (mutualTLS, DPoP, Signature) > negotiable (oauth2 authorizationCode/clientCredentials, openIdConnect) > bearer (http bearer, apiKey)
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link

10 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Access Clarity scores 7.9 — up to +18.4 composite points
Developer Ergonomics scores 26.2 — up to +14.8 composite points
Contract Quality scores 54.8 — up to +11.3 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

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 the provider profile at artifacts.apis.io/openssf/apis.yml: open an issue on github.com/api-evangelist/openssf to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

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.

OpenAPI

measured — observed by APIs.io (published)

APIs 7

Individual APIs this provider publishes, each with its own machine-readable definition.

Sigstore Public Good APIs

Sigstore is an OpenSSF-hosted standard and service for signing, verifying, and protecting software. The public-good Sigstore instance exposes Fulcio (code-signing certificate au...

GUAC (Graph for Understanding Artifact Composition)

GUAC aggregates software supply-chain security metadata (SBOMs, attestations, vulnerabilities, signatures) into a queryable graph. GUAC exposes a GraphQL API for supply-chain qu...

OpenSSF Projects API

The Projects API from OpenSSF — 1 operation(s) for projects.

OpenSSF Query API

The Query API from OpenSSF — 1 operation(s) for query.

OpenSSF Querybatch API

The Querybatch API from OpenSSF — 1 operation(s) for querybatch.

OpenSSF V1experimental API

The V1experimental API from OpenSSF — 2 operation(s) for v1experimental.

OpenSSF Vulns API

The Vulns API from OpenSSF — 1 operation(s) for vulns.

Scroll for all 7

Open Collections 7

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

OSV (Open Source Vulnerabilities) API

OPEN COLLECTION

OSV (Open Source Vulnerabilities) Projects API

OPEN COLLECTION

OSV (Open Source Vulnerabilities) Projects Query API

OPEN COLLECTION

OSV (Open Source Vulnerabilities) Projects Querybatch API

OPEN COLLECTION

OpenSSF Scorecard API

OPEN COLLECTION

OSV (Open Source Vulnerabilities) Projects V1experimental API

OPEN COLLECTION

OSV (Open Source Vulnerabilities) Projects Vulns API

OPEN COLLECTION

Scroll for all 7

GraphQL 1

GraphQL schemas published by this provider.

OpenSSF GraphQL API

GUAC aggregates software supply-chain security metadata (SBOMs, attestations, vulnerabilities, signatures) into a queryable graph. GUAC exposes a GraphQL API for supply-chain qu...

GRAPHQL

OpenSSF API pricing

Not yet checked against OpenSSF's own pricing page. Compiled by API Evangelist on 2026-05-04; confirm before you rely on a figure. A free plan or tier is listed.

Plan	Price
Free freemium	Free
Professional paid	Free
Enterprise enterprise	—

Plan details, limits and sources →

Rate limits

Free Tier Default: 10 requests per minute
Free Tier Monthly Quota: 1000 requests per month
Professional Tier Default: 100 requests per minute

Compiled by API Evangelist, not yet checked against OpenSSF's documentation. All 5 limits →

Pricing Plans 1

Published pricing tiers and plan structures.

Openssf Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Openssf Rate Limits

5 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

OpenSSF

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Openssf Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Openssf Context

7 classes · 0 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

OpenSSF — jsonschema rules

5 rules · 4 warnings 1 info

SPECTRAL

JSON Schema 1

Standalone JSON Schema definitions for this provider's data models.

OSV Vulnerability

14 properties

JSON SCHEMA

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Openssf Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Openssf Agentic Access

6 operations · 1 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

Portal

Portal

Documentation 2

Reference material describing how the API behaves

ContributionGuide

ContributionGuide

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 5

SDKs, sample code, and the tooling you integrate with

CodeOfConduct

CodeOfConduct

GitHubOrganization

GitHubOrganization

GitHubRepository

GitHubRepository

GitHubRepository

GitHubRepository

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

SecurityPolicy

SecurityPolicy

DomainSecurity

DomainSecurity

Operate 5

Status, limits, changes, and where to get help

RateLimits

IssueTracker

Releases

Community

Slack

Commercial 3

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

License

License

Company 3

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: openssf
name: OpenSSF
description: The Open Source Security Foundation (OpenSSF) is a collaborative initiative under the Linux Foundation dedicated
  to improving the security of open source software. It brings together industry leaders, developers, and security experts
  to address vulnerabilities, enhance supply chain security, and develop security tools and best practices. OpenSSF stewards
  a number of projects with public REST APIs, including the OSV (Open Source Vulnerabilities) database, the Scorecard automated
  security health-check service, and Sigstore signing infrastructure.
type: Index
deliveryModel:
  model: unknown
  license: Apache 2.0
  open_source: false
  commercial: false
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - license
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: low
  source:
  - plans
  - security
  generated: '2026-11-06'
  method: derived
position: Consuming
access: 3rd-Party
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/openssf.png
tags:
- Linux Foundation
- Open Source
- Security
- Supply Chain
- Vulnerabilities
tags_raw:
- Linux Foundation
- Open Source
- Security
- Supply Chain
- Vulnerabilities
- Open-Source
created: '2026-03-16'
modified: '2026-05-19'
url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/apis.yml
specificationVersion: '0.23'
apis:
- aid: openssf:sigstore-api
  name: Sigstore Public Good APIs
  description: Sigstore is an OpenSSF-hosted standard and service for signing, verifying, and protecting software. The public-good
    Sigstore instance exposes Fulcio (code-signing certificate authority) and Rekor (transparency log) APIs that can be queried
    programmatically to inspect signing certificates and transparency log entries.
  humanURL: https://www.sigstore.dev/
  baseURL: https://rekor.sigstore.dev
  tags:
  - Signing
  - Transparency Log
  - Supply Chain
  properties:
  - type: Documentation
    url: https://docs.sigstore.dev/
  - type: Documentation
    url: https://docs.sigstore.dev/logging/overview/
  - type: GitHubOrganization
    url: https://github.com/sigstore
- aid: openssf:guac-api
  name: GUAC (Graph for Understanding Artifact Composition)
  description: GUAC aggregates software supply-chain security metadata (SBOMs, attestations, vulnerabilities, signatures)
    into a queryable graph. GUAC exposes a GraphQL API for supply-chain queries when self-hosted.
  humanURL: https://guac.sh/
  baseURL: https://guac.sh
  tags:
  - SBOM
  - Supply Chain
  - GraphQL
  properties:
  - type: Documentation
    url: https://docs.guac.sh/
  - type: GitHubRepository
    url: https://github.com/guacsec/guac
  - url: graphql/openssf-graphql.md
    type: GraphQL
- aid: openssf:openssf-projects-api
  name: OpenSSF Projects API
  description: The Projects API from OpenSSF — 1 operation(s) for projects.
  humanURL: https://osv.dev/
  baseURL: https://api.osv.dev
  tags:
  - Project
  tags_raw:
  - Projects
  properties:
  - type: OpenAPI
    url: openapi/openssf-projects-api-openapi.yml
  - type: Documentation
    url: https://google.github.io/osv.dev/api/
  - type: Documentation
    url: https://osv.dev/
  - type: GitHubRepository
    url: https://github.com/google/osv.dev
  - type: GitHubRepository
    url: https://github.com/ossf/osv-schema
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-schema/openssf-osv-vulnerability-schema.json
  - type: JSONLDContext
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-ld/openssf-context.jsonld
  - type: Documentation
    url: https://github.com/ossf/scorecard
  - type: Documentation
    url: https://scorecard.dev/
- aid: openssf:openssf-query-api
  name: OpenSSF Query API
  description: The Query API from OpenSSF — 1 operation(s) for query.
  humanURL: https://osv.dev/
  baseURL: https://api.osv.dev
  tags:
  - Query
  properties:
  - type: OpenAPI
    url: openapi/openssf-query-api-openapi.yml
  - type: Documentation
    url: https://google.github.io/osv.dev/api/
  - type: Documentation
    url: https://osv.dev/
  - type: GitHubRepository
    url: https://github.com/google/osv.dev
  - type: GitHubRepository
    url: https://github.com/ossf/osv-schema
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-schema/openssf-osv-vulnerability-schema.json
  - type: JSONLDContext
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-ld/openssf-context.jsonld
  - type: Documentation
    url: https://github.com/ossf/scorecard
  - type: Documentation
    url: https://scorecard.dev/
- aid: openssf:openssf-querybatch-api
  name: OpenSSF Querybatch API
  description: The Querybatch API from OpenSSF — 1 operation(s) for querybatch.
  humanURL: https://osv.dev/
  baseURL: https://api.osv.dev
  tags:
  - Querybatch
  properties:
  - type: OpenAPI
    url: openapi/openssf-querybatch-api-openapi.yml
  - type: Documentation
    url: https://google.github.io/osv.dev/api/
  - type: Documentation
    url: https://osv.dev/
  - type: GitHubRepository
    url: https://github.com/google/osv.dev
  - type: GitHubRepository
    url: https://github.com/ossf/osv-schema
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-schema/openssf-osv-vulnerability-schema.json
  - type: JSONLDContext
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-ld/openssf-context.jsonld
  - type: Documentation
    url: https://github.com/ossf/scorecard
  - type: Documentation
    url: https://scorecard.dev/
- aid: openssf:openssf-v1experimental-api
  name: OpenSSF V1experimental API
  description: The V1experimental API from OpenSSF — 2 operation(s) for v1experimental.
  humanURL: https://osv.dev/
  baseURL: https://api.osv.dev
  tags:
  - V1experimental
  properties:
  - type: OpenAPI
    url: openapi/openssf-v1experimental-api-openapi.yml
  - type: Documentation
    url: https://google.github.io/osv.dev/api/
  - type: Documentation
    url: https://osv.dev/
  - type: GitHubRepository
    url: https://github.com/google/osv.dev
  - type: GitHubRepository
    url: https://github.com/ossf/osv-schema
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-schema/openssf-osv-vulnerability-schema.json
  - type: JSONLDContext
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-ld/openssf-context.jsonld
  - type: Documentation
    url: https://github.com/ossf/scorecard
  - type: Documentation
    url: https://scorecard.dev/
- aid: openssf:openssf-vulns-api
  name: OpenSSF Vulns API
  description: The Vulns API from OpenSSF — 1 operation(s) for vulns.
  humanURL: https://osv.dev/
  baseURL: https://api.osv.dev
  tags:
  - Vulns
  properties:
  - type: OpenAPI
    url: openapi/openssf-vulns-api-openapi.yml
  - type: Documentation
    url: https://google.github.io/osv.dev/api/
  - type: Documentation
    url: https://osv.dev/
  - type: GitHubRepository
    url: https://github.com/google/osv.dev
  - type: GitHubRepository
    url: https://github.com/ossf/osv-schema
  - type: JSONSchema
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-schema/openssf-osv-vulnerability-schema.json
  - type: JSONLDContext
    url: https://raw.githubusercontent.com/api-evangelist/openssf/refs/heads/main/json-ld/openssf-context.jsonld
  - type: Documentation
    url: https://github.com/ossf/scorecard
  - type: Documentation
    url: https://scorecard.dev/
common:
- type: Plans
  url: plans/openssf-plans-pricing.yml
- type: RateLimits
  url: rate-limits/openssf-rate-limits.yml
- type: FinOps
  url: finops/openssf-finops.yml
- type: CapabilityMap
  url: capabilities/openssf-capability-edges.yml
  name: OpenSSF Business Capability Map
- type: IssueTracker
  url: https://github.com/guacsec/guac/issues
- type: Releases
  url: https://github.com/guacsec/guac/releases
- type: SecurityPolicy
  url: https://github.com/guacsec/guac/blob/main/SECURITY-INSIGHTS.yml
- type: CodeOfConduct
  url: https://github.com/guacsec/guac/blob/main/CODE_OF_CONDUCT.md
- type: ContributionGuide
  url: https://github.com/guacsec/guac/blob/main/CONTRIBUTING.md
- type: AgenticAccess
  url: agentic-access/openssf-agentic-access.yml
- type: DomainSecurity
  url: security/openssf-domain-security.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/openssf
- type: Website
  name: OpenSSF
  url: https://openssf.org/
- type: Documentation
  name: OpenSSF Documentation
  url: https://openssf.org/resources/
- type: Portal
  name: Projects Directory
  url: https://openssf.org/projects/
- type: Blog
  name: OpenSSF Blog
  url: https://openssf.org/blog/
- type: GitHubOrganization
  name: OpenSSF GitHub
  url: https://github.com/ossf
- type: GitHubRepository
  name: OSV Schema
  url: https://github.com/ossf/osv-schema
- type: GitHubRepository
  name: Scorecard
  url: https://github.com/ossf/scorecard
- type: GitHubOrganization
  name: Sigstore GitHub
  url: https://github.com/sigstore
- type: License
  name: Apache 2.0
  url: https://www.apache.org/licenses/LICENSE-2.0
- type: Community
  name: OpenSSF Community
  url: https://openssf.org/community/
- type: Slack
  name: OpenSSF Slack
  url: https://slack.openssf.org/
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

OpenSSF API — frequently asked questions

Does OpenSSF have an API?

Yes. APIs.io lists 7 APIs from OpenSSF, including Sigstore Public Good APIs, GUAC (Graph for Understanding Artifact Composition) and OpenSSF Projects API, and 4 more.

Is there an OpenAPI specification for the OpenSSF API?

Yes. APIs.io indexes 5 OpenAPI specifications for OpenSSF, each linked for download from this page.

How much does the OpenSSF API cost?

APIs.io lists 3 pricing plans for OpenSSF, with each plan's price, limits and inclusions under Pricing on this page.

Is the OpenSSF API ready for AI agents?

OpenSSF has a Kin Score of 31.7 out of 100 (thin) and an Agent Readiness score of 17.2 (agent-aware), scored by API Evangelist on 2026-11-06.

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for providers

9 MCP tools reach this

find_providersBrowse and filter every provider in the catalog.
get_provider_artifactsEvery artifact this provider publishes, grouped by type.
get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This provider

curl "https://apis.io/api/v1/providers/openssf"

All providers

curl "https://apis.io/api/v1/providers?limit=25"

Every operation they expose

curl "https://apis.io/api/v1/providers/openssf/operations?limit=25"

How their score was established

curl "https://apis.io/api/v1/providers/openssf/evidence"

Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.

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.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.