Start here

ARPA is easier to navigate when you begin with the decision you need to make, not with the repository directory structure.

Choose your journey

You need to… Go to Primary outcome
Understand ARPA’s trust and authority model 1. Understand ARPA Correct conceptual boundaries and module selection
Implement or evaluate code 2. Build ARPA Working protocol implementation
Test a conformance or release claim 3. Assure & Conform Machine-verifiable assurance evidence
Deploy or govern a registry 4. Operate ARPA Operational controls and readiness evidence
Connect A2A, TRQP or another system 5. Integrate & Interoperate Explicit protocol-boundary mapping
Contribute, release or review governance 6. Govern & Contribute Reviewable change-control and repository evidence

Version boundary

  • Current normative project baseline: ARPA Candidate Specification v0.10.0.
  • Historical provenance: Candidate v0.9.0 plus the adversarial-hardening, PP-01, PP-02 and PP-03 amendment artifacts remain retained for auditability; they are no longer meant to be manually overlaid to determine current requirements.
  • Current implementation release line: v0.9.5 remains the independently versioned implementation and cross-runtime interoperability release. The GitHub v0.10.0 release is a Candidate Specification consolidation release, not an implementation v0.10.0 claim.

Guides and implementation code do not silently redefine normative requirements. Optional profiles become normative only when that profile is claimed.

Developer shortcut

If you are here to build something, start with Build ARPA, then run make release-check-all and review the evidence described in Assure & Conform.

For every rendered document and historical release note, use the Documentation catalogue.

Standards engagement

ARPA maintains a separate IETF Internet-Draft authoring track for the interoperable protocol core. The current published revision is draft-sankarshan-agent-registry-protocol-02, published on 23 September 2026. It is an independently versioned publication surface and does not replace the ARPA Candidate Specification.

For future -03 work, use two explicit baselines:

  • IETF comparison baseline: published -02, which is immutable.
  • Current ARPA source baseline: Candidate v0.10.0, from which protocol-core propositions may be selected through explicit disposition.

Project-only governance, conformance, assurance, deployment and implementation material does not enter a later Internet-Draft automatically.

Use this path when reviewing ARPA for IETF protocol extraction, revision deltas, IANA requirements, or overlap with adjacent IETF work.


Agent Registry Protocol documentation. Specification text and documentation are licensed as stated in the repository NOTICE and license files.

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