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 5 APIs on the APIs.io network, including Projects API, Query API, Querybatch API, and 2 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 16 more developer resources.

🌐 Visit website 📡 Source on GitHub

35.6/100 thin ▬ flat Agent 17/100 agent aware Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessFreemium

2 APIs

Linux Foundation Open-Source Security Supply Chain Vulnerabilities

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 35.6/100 · thin

Contract Quality 13.6 / 23

Developer Ergonomics 4.7 / 18

Access Clarity 2.8 / 18

Operational Transparency 4.3 / 12

Contract Governance 1.1 / 11

Discoverability 6.2 / 9

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

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/openssf: 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 →

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 8

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

API Collection

OPEN COLLECTION

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 8

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

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

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 API 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 · 3 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 4

Status, limits, changes, and where to get help

IssueTracker

Releases

Community

Slack

Commercial 1

Pricing, plans, and the legal terms of use

License

License

Company 3

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

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: medium
  source:
  - plans
  generated: '2026-07-22'
  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
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: 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

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