Struct KernelConfig 

pub struct KernelConfig {
    pub name: String,
    pub vfs_mode: VfsMountMode,
    pub cwd: PathBuf,
    pub skip_validation: bool,
    pub interactive: bool,
    pub ignore_config: IgnoreConfig,
    pub output_limit: OutputLimitConfig,
    pub allow_external_commands: bool,
    pub latch_enabled: bool,
    pub trash_enabled: bool,
    pub nonce_store: Option<NonceStore>,
}

Configuration for kernel initialization.

Fields

name: String

Name of this kernel (for identification).

vfs_mode: VfsMountMode

VFS mount mode — controls how local filesystem is exposed.

cwd: PathBuf

Initial working directory (VFS path).

skip_validation: bool

Whether to skip pre-execution validation.

When false (default), scripts are validated before execution to catch errors early. Set to true to skip validation for performance or to allow dynamic/external commands.

interactive: bool

When true, standalone external commands inherit stdio for real-time output.

Set by script runner and REPL for human-visible output. Not set by MCP server (output must be captured for structured responses).

ignore_config: IgnoreConfig

Ignore file configuration for file-walking tools.

output_limit: OutputLimitConfig

Output size limit configuration for agent safety.

allow_external_commands: bool

Whether external command execution (PATH lookup, exec, spawn) is allowed.

When true (default), commands not found as builtins are resolved via PATH and executed as child processes. When false, only kaish builtins and backend-registered tools (MCP) are available.

Security: External commands bypass the VFS sandbox entirely — they see the real filesystem, network, and environment. Set to false when running untrusted input.

latch_enabled: bool

Enable confirmation latch for dangerous operations (set -o latch).

When enabled, destructive operations like rm require nonce confirmation. Can also be enabled at runtime with set -o latch or via KAISH_LATCH=1.

trash_enabled: bool

Enable trash-on-delete for rm (set -o trash).

When enabled, small files are moved to freedesktop.org Trash instead of being permanently deleted. Can also be enabled at runtime with set -o trash or via KAISH_TRASH=1.

nonce_store: Option<NonceStore>

Shared nonce store for cross-request confirmation latch.

When Some, the kernel uses this store instead of creating a fresh one. This allows nonces issued in one MCP execute() call to be validated in a subsequent call. When None (default), a fresh store is created.

Implementations

impl KernelConfig

pub fn transient() -> Self

Create a transient kernel config (sandboxed, for temporary use).

pub fn named(name: &str) -> Self

Create a kernel config with the given name (sandboxed by default).

pub fn repl() -> Self

Create a REPL config with passthrough filesystem access.

Native paths like /home/user/project work directly. The cwd is set to the actual current working directory.

pub fn mcp() -> Self

Create an MCP server config with sandboxed filesystem access.

Local filesystem is accessible at its real path (e.g., /home/user), but sandboxed to $HOME. Paths outside the sandbox are not accessible through builtins. External commands still access the real filesystem — use .with_allow_external_commands(false) to block them.

pub fn mcp_with_root(root: PathBuf) -> Self

Create an MCP server config with a custom sandbox root.

Use this to restrict access to a subdirectory like ~/src.

pub fn isolated() -> Self

Create a config with no local filesystem (memory only).

Complete isolation: no local filesystem and external commands are disabled. Useful for tests or pure sandboxed execution.

pub fn with_vfs_mode(self, mode: VfsMountMode) -> Self

Set the VFS mount mode.

pub fn with_cwd(self, cwd: PathBuf) -> Self

Set the initial working directory.

pub fn with_skip_validation(self, skip: bool) -> Self

Skip pre-execution validation.

pub fn with_interactive(self, interactive: bool) -> Self

Enable interactive mode (external commands inherit stdio).

pub fn with_ignore_config(self, config: IgnoreConfig) -> Self

Set the ignore file configuration.

pub fn with_output_limit(self, config: OutputLimitConfig) -> Self

Set the output limit configuration.

pub fn with_allow_external_commands(self, allow: bool) -> Self

Set whether external command execution is allowed.

When false, commands not found as builtins produce “command not found” instead of searching PATH. The exec and spawn builtins also return errors. Use this to prevent VFS sandbox bypass via external binaries.

pub fn with_latch(self, enabled: bool) -> Self

Enable or disable confirmation latch at startup.

pub fn with_trash(self, enabled: bool) -> Self

Enable or disable trash-on-delete at startup.

pub fn with_nonce_store(self, store: NonceStore) -> Self

Use a shared nonce store for cross-request confirmation latch.

Pass a NonceStore that outlives individual kernel instances so nonces issued in one MCP execute() call can be validated in subsequent calls.

Trait Implementations

impl Clone for KernelConfig

fn clone(&self) -> KernelConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for KernelConfig

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

Formats the value using the given formatter.

impl Default for KernelConfig

fn default() -> Self

Returns the “default value” for a type.