Yearn Finance

Yearn Finance is a DeFi yield aggregator that automates yield farming strategies across EVM-compatible networks. It provides REST and GraphQL APIs for accessing vault data, APY rates, strategy information, user positions, TVL metrics, and protocol analytics across Ethereum, Optimism, Polygon, Fantom, Base, and Arbitrum.

Yearn Finance publishes 4 APIs on the APIs.io network, including Chains API, Info API, TVL API, and 1 more. Tagged areas include DeFi, Yield Aggregator, Vault, EVM, and Web3.

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

🌐 Visit website 📡 Source on GitHub

30.5/100 thin ▬ flat Agent 23/100 agent aware Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0

AccessFreeOpen⚡ Free to try

5 APIs

DeFiYield AggregatorVault EVM Web3 Blockchain Finance

Kin Score

Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0

Composite quality — 30.5/100 · thin

Contract Quality 15.4 / 25

Developer Ergonomics 0.0 / 20

Access Clarity 5.8 / 20

Operational Transparency 0.0 / 13

Contract Governance 1.2 / 12

Discoverability 8.2 / 10

Agent readiness — 23/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 9 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 7 / 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 4 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Surface 0 / 5

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/yearn: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 5

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

Kong GraphQL API

An integrated indexing service and GraphQL API providing comprehensive data on Yearn V2 and V3 vault ecosystems, including contract snapshots, event histories, vault-strategy re...

Yearn Finance Chains API

Supported blockchain network information

Yearn Finance Info API

Protocol information and metadata

Yearn Finance TVL API

Total Value Locked metrics

Yearn Finance Vaults API

Endpoints for querying Yearn vault data

Open Collections 5

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

API Collection

OPEN COLLECTION

Yearn Finance yDaemon REST Chains API

OPEN COLLECTION

Yearn Finance yDaemon REST Chains Info API

OPEN COLLECTION

Yearn Finance yDaemon REST Chains TVL API

OPEN COLLECTION

Yearn Finance yDaemon REST Chains Vaults API

OPEN COLLECTION

GraphQL 1

GraphQL schemas published by this provider.

Rate Limits 1

Documented rate limits and quota policies.

Rate Limits

0 limits

RATE LIMITS

FinOps 1

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

JSON Schema 1

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

AGENTIC

Resources

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Commercial 1

Pricing, plans, and the legal terms of use

License

License

Source (apis.yml)

name: Yearn Finance
description: Yearn Finance is a DeFi yield aggregator that automates yield farming strategies across EVM-compatible networks.
  It provides REST and GraphQL APIs for accessing vault data, APY rates, strategy information, user positions, TVL metrics,
  and protocol analytics across Ethereum, Optimism, Polygon, Fantom, Base, and Arbitrum.
specificationVersion: '0.23'
accessModel:
  pricing: free
  onboarding: open
  trial: false
  try_now: true
  public: true
  label: Free · Open access
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://yearn.fi/logo.svg
tags:
- DeFi
- Yield Aggregator
- Vault
- EVM
- Web3
- Blockchain
- Finance
tags_raw:
- DeFi
- Yield Aggregator
- Vaults
- EVM
- Web3
- Blockchain
- Finance
url: https://yearn.fi
apis:
- name: Kong GraphQL API
  description: An integrated indexing service and GraphQL API providing comprehensive data on Yearn V2 and V3 vault ecosystems,
    including contract snapshots, event histories, vault-strategy relationships, fees, rewards, APY, and TVL timeseries data.
  humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
  baseURL: https://kong.yearn.fi
  tags:
  - GraphQL
  - Vault
  - Analytics
  - Strategies
  - Event
  tags_raw:
  - GraphQL
  - Vaults
  - Analytics
  - Strategies
  - Events
  properties:
  - type: Documentation
    url: https://docs.yearn.fi/developers/data-services/yearn-data
  - type: GitHubRepository
    url: https://github.com/yearn/kong
  contact:
  - FN: Yearn Finance
    email: ''
    X-twitter: iearnfinance
  apis:
  - name: Kong GraphQL Query
    description: GraphQL endpoint for querying Yearn V2 and V3 vault ecosystem data including snapshots, events, APY timeseries,
      TVL, strategies, fees, rewards, and vault metadata.
    humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
    baseURL: https://kong.yearn.fi
    path: /api/gql
    method: POST
    tags:
    - GraphQL
    - Vault
    - Analytics
    tags_raw:
    - GraphQL
    - Vaults
    - Analytics
    properties:
    - type: Documentation
      url: https://docs.yearn.fi/developers/data-services/yearn-data
- aid: yearn:yearn-chains-api
  name: Yearn Finance Chains API
  description: Supported blockchain network information
  humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
  baseURL: https://ydaemon.yearn.fi
  tags:
  - Chains
  properties:
  - type: OpenAPI
    url: openapi/yearn-chains-api-openapi.yml
  - type: Documentation
    url: https://docs.yearn.fi/developers/data-services/yearn-data
  - type: GitHubRepository
    url: https://github.com/yearn/ydaemon
  - type: GraphQL
    url: graphql/yearn-graphql.md
- aid: yearn:yearn-info-api
  name: Yearn Finance Info API
  description: Protocol information and metadata
  humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
  baseURL: https://ydaemon.yearn.fi
  tags:
  - Info
  properties:
  - type: OpenAPI
    url: openapi/yearn-info-api-openapi.yml
  - type: Documentation
    url: https://docs.yearn.fi/developers/data-services/yearn-data
  - type: GitHubRepository
    url: https://github.com/yearn/ydaemon
  - type: GraphQL
    url: graphql/yearn-graphql.md
- aid: yearn:yearn-tvl-api
  name: Yearn Finance TVL API
  description: Total Value Locked metrics
  humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
  baseURL: https://ydaemon.yearn.fi
  tags:
  - TVL
  properties:
  - type: OpenAPI
    url: openapi/yearn-tvl-api-openapi.yml
  - type: Documentation
    url: https://docs.yearn.fi/developers/data-services/yearn-data
  - type: GitHubRepository
    url: https://github.com/yearn/ydaemon
  - type: GraphQL
    url: graphql/yearn-graphql.md
- aid: yearn:yearn-vaults-api
  name: Yearn Finance Vaults API
  description: Endpoints for querying Yearn vault data
  humanURL: https://docs.yearn.fi/developers/data-services/yearn-data
  baseURL: https://ydaemon.yearn.fi
  tags:
  - Vault
  tags_raw:
  - Vaults
  properties:
  - type: OpenAPI
    url: openapi/yearn-vaults-api-openapi.yml
  - type: Documentation
    url: https://docs.yearn.fi/developers/data-services/yearn-data
  - type: GitHubRepository
    url: https://github.com/yearn/ydaemon
  - type: GraphQL
    url: graphql/yearn-graphql.md
modified: 2026-06-13
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
common:
- type: License
  name: MIT
  url: https://github.com/yearn/kong/blob/main/LICENSE
- type: AgenticAccess
  url: agentic-access/yearn-agentic-access.yml
- type: DomainSecurity
  url: security/yearn-domain-security.yml

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Yearn Finance

APIs 5

Open Collections 5

GraphQL 1

Pricing Plans 1

Rate Limits 1

FinOps 1

Semantic Vocabularies 1

Spectral Rules 1

JSON Schema 1

Security Posture 1

Agentic Access 1

Agent Surfaces 1

Access & Security 1

Commercial 1

Source (apis.yml)

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