@spec build_capabilities(String.t()) :: map()

Build a legacy initialize-result wrapper using the canonical capability registry.

This function is retained as a 1.x compatibility shim. Initialization is handled by ExMCP's server dispatchers; code that only needs the capability map should use ExMCP.Server.Capabilities.build_capabilities/2.

@spec latest_version() :: String.t()

Get the newest legacy revision supported by initialize negotiation.

Modern MCP 2026-07-28 uses server/discover and is selected with a protocol mode instead of this legacy negotiator.

@spec negotiate([String.t()]) :: {:ok, String.t()} | {:error, :no_compatible_version}

Negotiates a legacy protocol revision from the client's offered versions.

Takes the client's supported versions and returns the best matching version that both client and server support.

Parameters

• client_versions - List of protocol versions supported by the client

Returns

• {:ok, version} - Successfully negotiated version
• {:error, :no_compatible_version} - No compatible version found

Examples

iex> ExMCP.Protocol.VersionNegotiator.negotiate(["2025-11-25", "2025-06-18"])
{:ok, "2025-11-25"}

iex> ExMCP.Protocol.VersionNegotiator.negotiate(["2024-01-01"])
{:error, :no_compatible_version}

@spec supported?(String.t()) :: boolean()

Checks whether a revision is supported by legacy initialize negotiation.

@spec supported_versions() :: [String.t()]

Returns the initialize-compatible legacy revisions.

Use ExMCP.Types.V20260728 and a modern-enabled :protocol_mode for MCP 2026-07-28 rather than expecting it in this list.