Crux

Crux is a capital platform for the clean economy, connecting clean energy and manufacturing developers with buyers, lenders, and investors. Its marketplace facilitates the sale of transferable clean energy tax credits created under the Inflation Reduction Act, alongside debt capital markets, tax equity, and preferred equity solutions and advisory services. Crux pairs a transaction platform and secure data room with market intelligence drawn from tens of billions of dollars in deal data, serving project developers, manufacturers, tax credit buyers, banks, tax advisors, and legal teams. The company is backed by Andreessen Horowitz (a16z) and was added to the API Evangelist network as a portfolio lead. Crux operates a customer application but does not publish a public developer API or OpenAPI at this time.

Crux is profiled on the APIs.io network. Tagged areas include Company, Clean Energy, Climate Finance, Tax Credits, and Capital Markets.

Crux’s developer surface includes engineering blog, signup flow, support, and 12 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

15.6/100 emerging ▬ flat Agent 0/100 human only Front door AI 3/6 light Heartbeat 100/100 alive saas Full breakdown ↓
scored 2026-11-13 · rubric v0.28.0 · Show this score on your site →

0 APIs

Company Clean EnergyClimate FinanceTax Credits Capital Markets Fintech Energy Marketplace Sustainability

Kin Score

Kin Score How this is scored →
scored 2026-11-13 · rubric v0.28.0

Composite quality — 15.6/100 · emerging

Contract Quality 0.0 / 21

Developer Ergonomics 1.2 / 17

Access Clarity 8.3 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 4.1 / 9

Regulatory Posture 1.6 / 15

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 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 0 / 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 Energy & Utilities 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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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

Machine-Readable Contract +18 pts — api_specs includes an OpenAPI document Ask about this →
MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship Ask about this →
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author Ask about this →
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) Ask about this →
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) Ask about this →
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes Ask about this →

13 more unmet checks in the Agent Readiness table above.

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

Contract Quality scores 0.0 — up to +25.0 composite points Ask about this →
Developer Ergonomics scores 7.1 — up to +18.6 composite points Ask about this →
Operational Transparency scores 0.0 — up to +13.0 composite points Ask about this →

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.

Not sure how this applies to your stack? Ask about any one item. Kin Lane reads every question, looks at your profile and your situation, and replies with what a fix would take — scoped to that one area, priced up front, yours whether you ship it or not. Ask a question →

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/crux/apis.yml: open an issue on github.com/api-evangelist/crux 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 →

Terms of Service 1

What its API terms permit and prohibit, quoted from its own page.

Crux

10 quoted statements, read from Crux's own page on 2026-11-09.

TERMS

Privacy & Data 1

Its role, the data it processes, retention and transfers, quoted from its own privacy page.

Crux

11 quoted statements, read from Crux's own page on 2026-11-09.

PRIVACY

Compliance 1

Attestations the provider states (SOC 2, ISO 27001 and others), quoted from its own trust page. APIs.io verifies none of them.

Crux

1 quoted statement, read from Crux's own page on 2026-11-09.

COMPLIANCE

Eligibility 1

Who may sign up and where, quoted from its own terms.

Crux

5 quoted statements, read from Crux's own page on 2026-11-09.

ELIGIBILITY

AI Preferences 1

Its stance on AI training, inference and agents, quoted from its own pages.

Crux

1 quoted statement, read from Crux's own page on 2026-11-09.

AI PREFS

Data License 1

How its data and outputs may be reused, quoted from its own terms.

Crux

2 quoted statements, read from Crux's own page on 2026-11-09.

LICENSE

Security Posture 2

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

Crux Domain Security

TLSv1.3 · HSTS

SECURITY

Crux Trust Center

SOC 2 Type 2

SECURITY

Resources

Get Started 1

Portal, sign-up, and the first successful call

SignUp

SignUp

Documentation 1

Reference material describing how the API behaves

AIPreferences

AIPreferences

Access & Security 3

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Compliance

Compliance

TrustCenter

TrustCenter

Operate 1

Status, limits, changes, and where to get help

Support

Support

Commercial 4

Pricing, plans, and the legal terms of use

TermsOfService

PrivacyPolicy

UsageTerms

DataLicense

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 3

Properties that don't map to a standard resource type

DataProcessing

DataProcessing

Attestations

Attestations

Eligibility

Eligibility

Source (apis.yml)

aid: crux
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - security
  generated: '2026-11-13'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/crux.png
name: Crux
description: Crux is a capital platform for the clean economy, connecting clean energy and manufacturing developers with buyers,
  lenders, and investors. Its marketplace facilitates the sale of transferable clean energy tax credits created under the
  Inflation Reduction Act, alongside debt capital markets, tax equity, and preferred equity solutions and advisory services.
  Crux pairs a transaction platform and secure data room with market intelligence drawn from tens of billions of dollars in
  deal data, serving project developers, manufacturers, tax credit buyers, banks, tax advisors, and legal teams. The company
  is backed by Andreessen Horowitz (a16z) and was added to the API Evangelist network as a portfolio lead. Crux operates a
  customer application but does not publish a public developer API or OpenAPI at this time.
url: https://raw.githubusercontent.com/api-evangelist/crux/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- a16z
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-18'
tags:
- Company
- Clean Energy
- Climate Finance
- Tax Credits
- Capital Markets
- Fintech
- Energy
- Marketplace
- Sustainability
apis: []
common:
- type: DomainSecurity
  url: security/crux-domain-security.yml
- type: Website
  url: https://www.crux.com/
- type: Blog
  url: https://www.crux.com/blog
- type: SignUp
  url: https://app.cruxclimate.com/login
- type: Support
  url: https://www.crux.com/contact
- type: TermsOfService
  url: https://www.crux.com/terms-of-service
- type: PrivacyPolicy
  url: https://www.crux.com/privacy-policy
- type: Compliance
  url: https://www.crux.com/security
- type: TrustCenter
  url: security/crux-trust-center.yml
- type: UsageTerms
  url: terms/crux-terms-of-service.yml
- type: DataProcessing
  url: privacy/crux-privacy-policy.yml
- type: Attestations
  url: compliance/crux-compliance.yml
- type: Eligibility
  url: eligibility/crux-eligibility.yml
- type: AIPreferences
  url: ai-preferences/crux-ai-preferences.yml
- type: DataLicense
  url: data-license/crux-data-license.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

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