Plinth US Grants Data

A JSON API over the entire US grantmaking universe — about 205,000 grantmaking foundations and 17.9 million grants, read from public IRS Form 990, 990-EZ and 990-PF e-file filings and the IRS Business Master File. The funder-grantee graph traverses in both directions: filter by funder_id for everything a foundation funded, or by recip_id for every funder behind a nonprofit. Offers REST endpoints for grants, organization profiles, an IRS compliance and OFAC screen, an ad-hoc read-only SQL endpoint over a 31-table warehouse, and a hosted OAuth 2.1 MCP connector for AI agents. Entity resolution is free and unmetered. Published by Plinth, trading name of Time to Spare Ltd (UK Companies House 11530023), which also operates plinth.org.uk in the UK.

Plinth US Grants Data publishes 5 APIs on the APIs.io network, including Analyze API, Grants API, Organizations API, and 2 more. Tagged areas include Philanthropy, Grants, Non-Profit, Foundations, and IRS 990.

The Plinth US Grants Data catalog on APIs.io includes 1 Spectral governance ruleset.

Plinth US Grants Data’s developer surface includes documentation, API reference, getting-started guide, support, pricing, signup flow, authentication, and 21 more developer resources.

🌐 Visit website 📡 Source on GitHub

67.4/100 exemplar ▬ flat Agent 50/100 agent ready saas Full breakdown ↓
scored 2026-09-06 · rubric v0.19.0

AccessFreemiumSelf serve⚡ Free to try

1 APIs 2 MCP Servers

Philanthropy Grants Non-Profit FoundationsIRS 990Open DataGovernment SpendingResearch Agents REST JSON MCP SQL

Kin Score

Kin Score How this is scored →
scored 2026-09-06 · rubric v0.19.0

Composite quality — 67.4/100 · exemplar

Contract Quality 12.1 / 21

Developer Ergonomics 9.6 / 17

Access Clarity 13.0 / 17

Operational Transparency 1.2 / 11

Contract Governance 8.0 / 10

Discoverability 6.5 / 9

Regulatory Posture 11.4 / 15

Agent readiness — 50/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 5 / 5

Well-Known Catalog 4 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 5 / 5

Registration Without a Human 6 / 6

Agentic Commerce Well-Known Document 0 / 5

Regulatory Posture applies to this provider. Its tags matched the Government & Public Sector 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.

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/.

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/plinth-us-grants-data: 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 5

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

MCP Servers 2

Model Context Protocol servers that expose these APIs to AI agents.

Rate Limits 1

Documented rate limits and quota policies.

Scopes 1

OAuth scopes governing access to this provider's APIs.

Plinth Us Grants Data Scopes

OAuth 2.0 · no documented scopes

0 scopes

SCOPES

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Login

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

MCPServer

MCPServer

WellKnown

AgentSkill

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

Conformance

Conformance

Lifecycle

Lifecycle

Vocabulary

Vocabulary

Build 1

SDKs, sample code, and the tooling you integrate with

Packages

Packages

Access & Security 6

Authentication, authorization, and security posture

Authentication

Authentication

OAuthScopes

OAuthScopes

Security

Security

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

SecurityTxt

SecurityTxt

Operate 2

Status, limits, changes, and where to get help

Support

Support

Contact

Contact

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Other 2

Properties that don't map to a standard resource type

Overlay

Overlay

APICatalog

APICatalog

Source (apis.yml)

name: Plinth US Grants Data
description: 'A JSON API over the entire US grantmaking universe — about 205,000 grantmaking foundations and 17.9 million
  grants, read from public IRS Form 990, 990-EZ and 990-PF e-file filings and the IRS Business Master File. The funder-grantee
  graph traverses in both directions: filter by funder_id for everything a foundation funded, or by recip_id for every funder
  behind a nonprofit. Offers REST endpoints for grants, organization profiles, an IRS compliance and OFAC screen, an ad-hoc
  read-only SQL endpoint over a 31-table warehouse, and a hosted OAuth 2.1 MCP connector for AI agents. Entity resolution
  is free and unmetered. Published by Plinth, trading name of Time to Spare Ltd (UK Companies House 11530023), which also
  operates plinth.org.uk in the UK.'
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  - scopes
  - rate-limits
  - security
  generated: '2026-09-02'
  method: derived
image: https://data.useplinth.com/plinth-logo.svg
url: https://raw.githubusercontent.com/api-evangelist/plinth-us-grants-data/refs/heads/main/apis.yml
created: '2026-08-13'
modified: '2026-08-14'
specificationVersion: '0.23'
tags:
- Philanthropy
- Grants
- Non-Profit
- Foundations
- IRS 990
- Open Data
- Government Spending
- Research
- Agents
- REST
- JSON
- MCP
- SQL
tags_raw:
- Philanthropy
- Grants
- Nonprofits
- Foundations
- IRS 990
- Open Data
- Government Spending
- Research
- Agents
- REST
- JSON
- MCP
- SQL
apis:
- aid: plinth-us-grants-data:plinth-us-grants-data-analyze-api
  name: Plinth US Grants Data Analyze API
  description: Plain-English questions answered with SQL the service writes itself.
  humanURL: https://data.useplinth.com/developers
  baseURL: https://data.useplinth.com/api
  tags:
  - Analyze
  properties:
  - type: OpenAPI
    url: openapi/plinth-us-grants-data-analyze-api-openapi.yml
  - type: Documentation
    url: https://data.useplinth.com/developers
  - type: LLMsTxt
    url: llms/plinth-us-grants-data-llms.txt
  - type: LLMsTxt
    url: https://data.useplinth.com/llms.txt
  - type: ToolCrosswalk
    url: mcp/plinth-us-grants-data-tool-crosswalk.yml
  - type: RateLimits
    url: rate-limits/plinth-us-grants-data-rate-limits.yml
  - type: ErrorCatalog
    url: errors/plinth-us-grants-data-problem-types.yml
  - type: DataModel
    url: data-model/plinth-us-grants-data-data-model.yml
  - type: Conventions
    url: conventions/plinth-us-grants-data-conventions.yml
  - type: SpectralRules
    url: rules/plinth-us-grants-data-spectral.yaml
  - type: SpectralRules
    url: https://data.useplinth.com/spectral/grants-api.yaml
- aid: plinth-us-grants-data:plinth-us-grants-data-grants-api
  name: Plinth US Grants Data Grants API
  description: 'The funder-grantee graph: grants, funders, recipients and aggregates.'
  humanURL: https://data.useplinth.com/developers
  baseURL: https://data.useplinth.com/api
  tags:
  - Grants
  properties:
  - type: OpenAPI
    url: openapi/plinth-us-grants-data-grants-api-openapi.yml
  - type: Documentation
    url: https://data.useplinth.com/developers
  - type: LLMsTxt
    url: llms/plinth-us-grants-data-llms.txt
  - type: LLMsTxt
    url: https://data.useplinth.com/llms.txt
  - type: ToolCrosswalk
    url: mcp/plinth-us-grants-data-tool-crosswalk.yml
  - type: RateLimits
    url: rate-limits/plinth-us-grants-data-rate-limits.yml
  - type: ErrorCatalog
    url: errors/plinth-us-grants-data-problem-types.yml
  - type: DataModel
    url: data-model/plinth-us-grants-data-data-model.yml
  - type: Conventions
    url: conventions/plinth-us-grants-data-conventions.yml
  - type: SpectralRules
    url: rules/plinth-us-grants-data-spectral.yaml
  - type: SpectralRules
    url: https://data.useplinth.com/spectral/grants-api.yaml
- aid: plinth-us-grants-data:plinth-us-grants-data-organizations-api
  name: Plinth US Grants Data Organizations API
  description: Per-organization profiles, financials and IRS compliance facets.
  humanURL: https://data.useplinth.com/developers
  baseURL: https://data.useplinth.com/api
  tags:
  - Organization
  tags_raw:
  - Organizations
  properties:
  - type: OpenAPI
    url: openapi/plinth-us-grants-data-organizations-api-openapi.yml
  - type: Documentation
    url: https://data.useplinth.com/developers
  - type: LLMsTxt
    url: llms/plinth-us-grants-data-llms.txt
  - type: LLMsTxt
    url: https://data.useplinth.com/llms.txt
  - type: ToolCrosswalk
    url: mcp/plinth-us-grants-data-tool-crosswalk.yml
  - type: RateLimits
    url: rate-limits/plinth-us-grants-data-rate-limits.yml
  - type: ErrorCatalog
    url: errors/plinth-us-grants-data-problem-types.yml
  - type: DataModel
    url: data-model/plinth-us-grants-data-data-model.yml
  - type: Conventions
    url: conventions/plinth-us-grants-data-conventions.yml
  - type: SpectralRules
    url: rules/plinth-us-grants-data-spectral.yaml
  - type: SpectralRules
    url: https://data.useplinth.com/spectral/grants-api.yaml
- aid: plinth-us-grants-data:plinth-us-grants-data-resolve-api
  name: Plinth US Grants Data Resolve API
  description: Turn an organization name into an EIN and a canonical URL. No key required.
  humanURL: https://data.useplinth.com/developers
  baseURL: https://data.useplinth.com/api
  tags:
  - Resolve
  properties:
  - type: OpenAPI
    url: openapi/plinth-us-grants-data-resolve-api-openapi.yml
  - type: Documentation
    url: https://data.useplinth.com/developers
  - type: LLMsTxt
    url: llms/plinth-us-grants-data-llms.txt
  - type: LLMsTxt
    url: https://data.useplinth.com/llms.txt
  - type: ToolCrosswalk
    url: mcp/plinth-us-grants-data-tool-crosswalk.yml
  - type: RateLimits
    url: rate-limits/plinth-us-grants-data-rate-limits.yml
  - type: ErrorCatalog
    url: errors/plinth-us-grants-data-problem-types.yml
  - type: DataModel
    url: data-model/plinth-us-grants-data-data-model.yml
  - type: Conventions
    url: conventions/plinth-us-grants-data-conventions.yml
  - type: SpectralRules
    url: rules/plinth-us-grants-data-spectral.yaml
  - type: SpectralRules
    url: https://data.useplinth.com/spectral/grants-api.yaml
- aid: plinth-us-grants-data:plinth-us-grants-data-sql-api
  name: Plinth US Grants Data SQL API
  description: Ad-hoc read-only SQL over the warehouse. Paid keys only.
  humanURL: https://data.useplinth.com/developers
  baseURL: https://data.useplinth.com/api
  tags:
  - SQL
  properties:
  - type: OpenAPI
    url: openapi/plinth-us-grants-data-sql-api-openapi.yml
  - type: Documentation
    url: https://data.useplinth.com/developers
  - type: LLMsTxt
    url: llms/plinth-us-grants-data-llms.txt
  - type: LLMsTxt
    url: https://data.useplinth.com/llms.txt
  - type: ToolCrosswalk
    url: mcp/plinth-us-grants-data-tool-crosswalk.yml
  - type: RateLimits
    url: rate-limits/plinth-us-grants-data-rate-limits.yml
  - type: ErrorCatalog
    url: errors/plinth-us-grants-data-problem-types.yml
  - type: DataModel
    url: data-model/plinth-us-grants-data-data-model.yml
  - type: Conventions
    url: conventions/plinth-us-grants-data-conventions.yml
  - type: SpectralRules
    url: rules/plinth-us-grants-data-spectral.yaml
  - type: SpectralRules
    url: https://data.useplinth.com/spectral/grants-api.yaml
maintainers:
- FN: Plinth (Time to Spare Ltd)
  email: data@useplinth.com
  organizationName: Plinth (Time to Spare Ltd)
  url: https://www.useplinth.com
  X-twitter: useplinth
generated:
  by: apis.io/add
  model: claude-opus-4-8
  confidence: 97
  at: '2026-08-13T20:59:07.936Z'
common:
- type: MCPServer
  url: https://data.useplinth.com/api/connector/mcp
- type: MCPServer
  url: mcp/plinth-us-grants-data-mcp.yml
- type: Overlay
  url: overlays/plinth-us-grants-data-grants-api-overlay.yaml
- type: DeveloperPortal
  url: https://data.useplinth.com/developers
- type: Documentation
  url: https://data.useplinth.com/developers
- type: APIReference
  url: https://data.useplinth.com/developers
- type: GettingStarted
  url: https://data.useplinth.com/developers#auth
- type: Support
  url: https://data.useplinth.com/developers#governance
- type: Contact
  url: mailto:data@useplinth.com
- type: Pricing
  url: https://data.useplinth.com/pricing
- type: SignUp
  url: https://data.useplinth.com/account
- type: Login
  url: https://data.useplinth.com/account
- type: TermsOfService
  url: https://www.useplinth.com/terms
- type: PrivacyPolicy
  url: https://www.useplinth.com/privacy
- type: Authentication
  url: authentication/plinth-us-grants-data-authentication.yml
- type: OAuthScopes
  url: scopes/plinth-us-grants-data-scopes.yml
- type: Security
  url: security/plinth-us-grants-data-vulnerability-disclosure.yml
- type: VulnerabilityDisclosure
  url: security/plinth-us-grants-data-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/plinth-us-grants-data-domain-security.yml
- type: WellKnown
  url: well-known/plinth-us-grants-data-well-known.yml
- type: SecurityTxt
  url: well-known/plinth-us-grants-data-security.txt
- type: APICatalog
  url: well-known/plinth-us-grants-data-api-catalog.json
- type: Conformance
  url: conformance/plinth-us-grants-data-conformance.yml
- type: Lifecycle
  url: lifecycle/plinth-us-grants-data-lifecycle.yml
- type: Vocabulary
  url: vocabulary/plinth-us-grants-data-vocabulary.yml
- type: Plans
  url: plans/plinth-us-grants-data-plans-pricing.yml
- type: Packages
  url: packages/plinth-us-grants-data-packages.yml
- type: AgentSkill
  url: skills/_index.yml
x-enrichment:
  date: '2026-08-14'
  status: enriched
  artifacts_added: 31
  pass: local-v1

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Plinth US Grants Data

Kin Score

APIs 5

Plinth US Grants Data Analyze API

Plinth US Grants Data Grants API

Plinth US Grants Data Organizations API

Plinth US Grants Data Resolve API

Plinth US Grants Data SQL API

MCP Servers 2

Plinth US Grants Data MCP Server

Plinth

Pricing Plans 1

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