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AutomotiveMCP
Spec§2RFC / v0.1

Conformance & Versioning

Levels of conformance, how versions are numbered, and the lifecycle a release moves through from draft to ratified.

2.1 Requirement keywords

The keywords MUST, MUST NOT, SHOULD, SHOULD NOT, and MAY in this document are to be interpreted as described in RFC 2119 and RFC 8174 when, and only when, they appear in capitals.

2.2 Conformance levels

A server declares the level it implements. Levels are additive.

  • Level 1 — Core Read. The server exposes the required read resources for the domains it supports, with conformant schemas and naming. Sufficient for agents that observe and report.
  • Level 2 — Tools. The server additionally exposes the required action tools (for example, creating a lead or booking a service appointment) with conformant inputs, outputs, and errors.
  • Level 3 — Eventing. The server additionally supports subscriptions/eventing for the resources it exposes, so agents can react to change rather than poll.

A server MUST NOT claim a level it does not fully meet for the domains it advertises. A server MAY support a subset of domains; it MUST declare which.

2.3 Versioning

The specification uses semantic versioning (MAJOR.MINOR.PATCH).

  • MAJOR — breaking changes to resource shapes, tool contracts, or naming.
  • MINOR — backwards-compatible additions (new optional fields, new tools, new domains).
  • PATCH — clarifications and editorial fixes with no contract impact.

A conformant server MUST advertise the specification version(s) it implements (see Reference). Agents MUST negotiate against the advertised version and MUST NOT assume fields outside it.

2.4 Lifecycle

Each release moves through a defined lifecycle:

StageMeaning
Draft (RFC)Open for public comment. Contracts may change. Current state of v0.1.
CandidateFeature-frozen; under partner review and reference-implementation testing.
RatifiedAdopted by the council. Changes follow the versioning rules above.
SupersededReplaced by a later MAJOR version; maintained for a stated deprecation window.

The current document is v0.1 (RFC). The governance model for how revisions are proposed and accepted is described on the Governance page.