Struct ShadowSentinelConfig 

pub struct ShadowSentinelConfig {
    pub enabled: bool,
    pub probe_provider: ProviderName,
    pub max_context_events: usize,
    pub probe_timeout_ms: u64,
    pub max_probes_per_turn: usize,
    pub probe_patterns: Vec<String>,
    pub deny_on_timeout: bool,
}

Configuration for the ShadowSentinel subsystem, nested under [security.shadow_sentinel].

ShadowSentinel is a defence-in-depth layer (Phase 2 of spec 050) that persists safety events across sessions and runs an LLM probe before high-risk tool execution. It is NOT the primary security gate — PolicyGateExecutor and TrajectorySentinel remain the primary enforcement mechanisms and are unaffected by probe timeouts.

Example (TOML)

[security.shadow_sentinel]
enabled = true
probe_provider = "fast"
probe_timeout_ms = 2000

Fields

enabled: bool

Whether the feature is enabled. Default: false (opt-in).

probe_provider: ProviderName

Provider name (from [[llm.providers]]) used for the safety probe LLM call.

Empty string means use the main/default provider. A fast, cheap provider (e.g. gpt-4o-mini) is strongly recommended to minimise turn latency.

max_context_events: usize

Maximum number of trajectory events to include in the probe context. Default: 50.

probe_timeout_ms: u64

Timeout for the probe LLM call in milliseconds. Default: 2000.

max_probes_per_turn: usize

Maximum probe calls per turn to cap LLM costs. Default: 3.

probe_patterns: Vec<String>

Glob patterns over fully-qualified tool ids that trigger the safety probe.

Default covers shell execution, file writes, and MCP file/exec tools.

deny_on_timeout: bool

When true, a probe timeout or LLM error causes the tool call to be denied. When false (default), a probe failure causes the call to be allowed (fail-open).

Fail-open is the correct default because:

• ShadowSentinel is defence-in-depth, not the primary gate.
• Failing closed on probe timeout would allow a DoS (slow context → disabled tools).
• PolicyGateExecutor + TrajectorySentinel continue to enforce policy regardless.

Trait Implementations

impl Clone for ShadowSentinelConfig

fn clone(&self) -> ShadowSentinelConfig

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ShadowSentinelConfig

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

Formats the value using the given formatter.

impl Default for ShadowSentinelConfig

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ShadowSentinelConfig

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for ShadowSentinelConfig

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.