KYAPay Token Exchange

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Table of Contents

1. Introduction

KYAPay tokens [I-D.skyfire-oauth-kyapay-token] are used by agents to identify themselves, the principal they are acting on behalf of, their payment capabilities, their authorized scope of action or mission, and their intended audience. Agents may need access to resources in order to accomplish their mission. This specification describes how an agent can present a KYAPay token to obtain an OAuth access token granting access to a resource that it needs to accomplish its mission.¶

2. Conventions and Definitions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.¶

3. KYAPay Token Exchange

The KYAPay token contains identifying information for both the principal on whose behalf the request is being made (in the Human Identity (hid) claim) and the agent that is authorized to act on behalf on the principal (in the Agent Platform Identity (apd) claim and/or in the Agent Identity (aid) claim). The token exchange is performed using the grant type urn:ietf:params:oauth:grant-type:jwt-bearer [RFC7523] at the authorization server's token endpoint. The KYAPay token is supplied as the assertion value. The protected resource that access is being requested for is supplied as the resource value [RFC8707].¶

Note that OAuth Token Exchange [RFC8693], which has a separate subject_token and actor_token values, is not used, since the KYAPay token has all the information needed to describe both parties for delegated authorization.¶

POST /token HTTP/1.1
Host: as.example.com
Content-Type: application/x-www-form-urlencoded

grant_type=urn:ietf:params:oauth:grant-type:jwt-bearer
&assertion=*KYAPay Token*
&resource=https://mcp.acme.example/

{
  "alg": "ES256",
  "kid": "BEDD-0",
  "typ": "kya+jwt"
}

{
  "env": "production",
  "ori": "https://app.skyfire.xyz",
  "itg": "cursor-agent",
  "tsi": "886eef79-4d90-4b8d-81f0-ce5c6c7dac13",
  "tdm": "auth101.dev",
  "hid": {
    "email": "example@skyfire.xyz",
    "verifier": "https://app.skyfire.xyz",
    "verified": true
  },
  "aid": {
    "name": "Buyer 1",
    "creation_ip": "12.50.206.98"
  },
  "apd": {
    "id": "a283ced5-95be-4abe-81aa-51552e8876ad",
    "name": "E2E Test Org 1",
    "email": "example@skyfire.xyz",
    "verifier": "https://app.skyfire.xyz",
    "verified": true
  },
  "scope": "",
  "iat": 1782245616,
  "iss": "https://app.skyfire.xyz",
  "jti": "019ef61d-eb8f-759b-9302-d998b294fcc9",
  "aud": "886eef79-4d90-4b8d-81f0-ce5c6c7dac13",
  "sub": "8fa1438f-8dd0-4e91-abb8-888cdbeb6d5d",
  "exp": 1782245916
}

{
  "alg": "ES256",
  "kid": "BEDD-0",
  "typ": "kya+jwt"
}

{
  "iss": "http://127.0.0.1:8788",
  "aud": "http://127.0.0.1:8799/mcp",
  "sub": "example@skyfire.xyz",
  "scope": "openid profile email mcp",
  "iat": 1782256825,
  "exp": 1782260425,
  "jti": "656ab7da-9c28-4dd4-a572-474af7ab47fe",
  "client_metadata": {
    "aid": "Buyer 1",
    "ori": "https://app-qa.skyfire.xyz"
  }
}

4. Security Considerations

The security considerations defined in [I-D.skyfire-oauth-kyapay-token] and [RFC7523] apply to this specification.¶

5. Privacy Considerations

The privacy considerations defined in [I-D.skyfire-oauth-kyapay-token] and [RFC7523] apply to this specification.¶

6. IANA Considerations

This specification requires no actions by IANA.¶

7. References

Document History

[[ to be removed by the RFC Editor before publication as an RFC ]]¶

-00¶

• Initial draft.¶

Contributors

Authors' Addresses