Fei Protocol

Fei Protocol was an Ethereum-based decentralized finance (DeFi) protocol that launched in April 2021, introducing FEI, an algorithmic stablecoin backed by Protocol Controlled Value (PCV), alongside the TRIBE governance token. Founded by Joey Santoro, it merged with Rari Capital in December 2021 to form the Tribe DAO. Following the April 2022 Rari Fuse exploit, the Tribe DAO voted to wind down and dissolve the protocol later that year. Fei Protocol was backed by a16z (Andreessen Horowitz), Framework Ventures, and other investors. Its smart-contract code and documentation remain public on GitHub, but the protocol is no longer operational and its web properties (fei.money, docs.fei.money) are offline. Fei Protocol is an on-chain smart-contract system and exposes no public REST/HTTP API, so it carries no OpenAPI, SDK, or hosted API artifacts.

Fei Protocol is profiled on the APIs.io network. Tagged areas include Company, DeFi, Stablecoins, Ethereum, and Smart Contracts.

📡 Profile data on GitHub

0.0/100 minimal ▬ flat Agent 0/100 human only Heartbeat 0/100 dormant Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

0 APIs

Company DeFi Stablecoins Ethereum Smart Contracts DAO Cryptocurrency Blockchain Governance Defunct

Kin Score

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

Composite quality — 0.0/100 · minimal

Contract Quality 0.0 / 21

Developer Ergonomics 0.0 / 17

Access Clarity 0.0 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 0.0 / 9

Regulatory Posture 0.0 / 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 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 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
MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
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

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
Developer Ergonomics scores 0.0 — up to +20.0 composite points
Access Clarity scores 0.0 — up to +20.0 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/fei-protocol/apis.yml: open an issue on github.com/api-evangelist/fei-protocol 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 →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Stablecoins and Tokenization (stablecoin issuers, tokenized assets)	undeclared	-	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

Resources

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Source (apis.yml)

aid: fei-protocol
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/fei-protocol.png
name: Fei Protocol
description: Fei Protocol was an Ethereum-based decentralized finance (DeFi) protocol that launched in April 2021, introducing
  FEI, an algorithmic stablecoin backed by Protocol Controlled Value (PCV), alongside the TRIBE governance token. Founded
  by Joey Santoro, it merged with Rari Capital in December 2021 to form the Tribe DAO. Following the April 2022 Rari Fuse
  exploit, the Tribe DAO voted to wind down and dissolve the protocol later that year. Fei Protocol was backed by a16z (Andreessen
  Horowitz), Framework Ventures, and other investors. Its smart-contract code and documentation remain public on GitHub, but
  the protocol is no longer operational and its web properties (fei.money, docs.fei.money) are offline. Fei Protocol is an
  on-chain smart-contract system and exposes no public REST/HTTP API, so it carries no OpenAPI, SDK, or hosted API artifacts.
url: https://raw.githubusercontent.com/api-evangelist/fei-protocol/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- a16z
x-tier: stub
x-tier-reason: portfolio-lead
x-status: defunct
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-09-16'
tags:
- Company
- DeFi
- Stablecoins
- Ethereum
- Smart Contracts
- DAO
- Cryptocurrency
- Blockchain
- Governance
- Defunct
tags_raw:
- Company
- DeFi
- Stablecoin
- Ethereum
- Smart Contracts
- DAO
- Cryptocurrency
- Blockchain
- Governance
- Defunct
common:
- type: GitHubOrganization
  url: https://github.com/fei-protocol
apis: []
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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