Enum McpCommand 

pub enum McpCommand {
    Npx {
        version: String,
    },
    NativeBinary {
        binary: PathBuf,
        version: String,
    },
    NodeLauncher {
        launcher: PathBuf,
        version: String,
    },
    Explicit(PathBuf),
    OnPath,
}

How the MCP server entry (and the skill’s bootstrap commands) invoke mushroomdb.

The assistant host spawns the MCP server by command, so that command has to resolve from its process, not from the shell install ran in. A bare name only works when it resolves on the host’s PATH, and the one case where that is provable is when the mushroomdb PATH resolves to is this very executable. Everything else — npm’s Node shim, a different build, a local target/release binary, no hit at all — pins the published package and lets npx fetch it.

Variants

Npx

npx -y mushroomdb@<version> … — the fallback when the package cannot be located, and the only form that works from a machine where nothing is installed globally.

Fields

version: String

NativeBinary

The published package’s own native binary, located once at install time and run directly. The fast form, and what a hook gets whenever the package has been fetched.

Everything else in this enum that reaches the published package ends up running this exact file; the difference is what it costs to get there. Measured warm, --version end to end: npx 514 ms, node <launcher> 118 ms, this 7 ms. Node’s own startup is nearly all of the difference — the launcher script’s only job is to spawn this binary — and a hook pays it on every prompt and every edit.

Fields

binary: PathBuf

Absolute path to the vendored executable.

version: String

The version it was resolved from; re-resolved on upgrade.

NodeLauncher

node <launcher.js> … — the same published package reached through its npm shim. The fallback for an install whose native binary could not be located (a postinstall that never fetched it, say): still resolved once rather than on every invocation, just through a Node startup.

Fields

launcher: PathBuf

Absolute path to the package’s bin script.

version: String

The version it was resolved from; re-resolved on upgrade.

Explicit(PathBuf)

An absolute path the user named with --command.

OnPath

mushroomdb resolves on PATH and is this executable: the bare name is safe and follows upgrades.

Implementations

impl McpCommand

pub fn npx() -> Self

The npx form pinned to the version of the binary writing it.

pub fn json_entry(&self, sub: &str, db: &str) -> Value

The MCP server entry: {"command": …, "args": [… , sub, db]}.

Nothing here is shell-quoted. An MCP host spawns the command with an argv, so a path with a space in it is one element and quoting it would make the quotes part of the filename.

pub fn shell(&self) -> String

The same invocation as a command prefix for a POSIX shell, already quoted where quoting is needed.

Hook entries and the skill’s copy-paste lines are read by a shell, so an explicit path — and a resolved binary or launcher path, which lives wherever npm put it — has to survive a space in it. The bare name and the npx form contain no metacharacters and are left as they read.

Trait Implementations

impl Clone for McpCommand

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for McpCommand

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for McpCommand

impl PartialEq for McpCommand

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for McpCommand