Module protocol_policy 

Exact MCP protocol-version identity and immutable era-policy selection.

This module intentionally models only the two supported protocol eras. It does not normalize date strings or treat intermediate protocol revisions as aliases. The crate-root integration is owned separately so that this policy surface can remain independent of transport classification and lifecycle state.

Structs

HttpEndpointBundle

Immutable, configured HTTP endpoint bundle for one policy selection.

HttpEndpointBundleKey

Opaque key for HTTP era negotiation and cached classification state.

HttpEraCache

Per-bundle era cache that cannot be contaminated by origin-only matches.

HttpModernProbe

One isolated response to the configured modern HTTP probe.

LegacyClientAdapterInstalledReceipt

Opaque, non-cloneable proof that the exact legacy client adapter is installed.

LegacyReceiptBinding

Immutable facts bound into a sealed legacy-adapter installation receipt.

LegacyServerAdapterInstalledReceipt

Opaque, non-cloneable proof that the exact legacy server adapter is installed.

ProtocolPolicySelection

A validated immutable policy and role.

ProtocolVersion

An exact, supported MCP protocol-version value.

StdioEraClassifier

One-shot era classifier owned by a single server-side stdio process.

Enums

HttpEndpointBundleError

Typed refusal while constructing a configured HTTP endpoint bundle.

HttpEraDecision

Era classification result for a configured HTTP bundle.

HttpProbeBody

The body category returned by one isolated modern HTTP probe.

HttpRouteKind

One explicit configured HTTP route before protocol parsing.

ModernVersionSupport

Modern-version support result after era selection.

ProtocolEra

A protocol era selected from one exact, supported protocol revision.

ProtocolPolicy

Immutable policy chosen before a client connects or a server binds.

ProtocolPolicyError

Typed policy-validation refusals raised before connect or bind side effects.

ProtocolRole

The role for which an immutable policy is validated.

ProtocolVersionError

Typed refusal for an unsupported protocol-version spelling.

StdioEraDecision

Deterministic result of considering one stdio frame.

StdioEraRejection

Typed refusal classes for invalid stdio era-selection traffic.

StdioEraState

The state of one server-side stdio process’s immutable era selection.

StdioOpeningFrame

The opening frame relevant to stdio era selection.

Constants

LEGACY_PROTOCOL_VERSION

The exact legacy MCP protocol revision supported by this policy surface.

MODERN_PROTOCOL_VERSION

The exact modern MCP protocol revision supported by this policy surface.

Traits

LegacyAdapterReceiptIssuer

Sealed issuer interface for the exact legacy-adapter installation path.