Struct PromptCachePlan 

pub struct PromptCachePlan {
    pub cache_tools: bool,
    pub cache_system: bool,
    pub breakpoint_message_ids: Vec<String>,
    pub ttl: CacheTtl,
}

Provider-agnostic description of which logical regions of a request form a stable, cacheable prefix.

Breakpoints are identified by message id rather than position so the plan survives provider-side message reshaping — for example, Anthropic merges consecutive tool-result messages into the preceding user message, which would invalidate positional indices.

Fields

cache_tools: bool

Cache the tool-definition block (stable for the whole session).

cache_system: bool

Cache the system prompt. Only set this when the system prompt is free of per-round volatile content (the engine guarantees this by moving volatile context blocks to the conversation tail).

breakpoint_message_ids: Vec<String>

Ids of messages that end a stable prefix; each becomes a cache breakpoint. Order is not significant.

ttl: CacheTtl

TTL hint for providers that support it.

Implementations

impl PromptCachePlan

pub fn disabled() -> Self

A plan that requests no caching.

pub fn is_enabled(&self) -> bool

True when the plan asks for at least one cache breakpoint.

pub fn is_breakpoint(&self, message_id: &str) -> bool

Whether the given message id is marked as a cache breakpoint.

Trait Implementations

impl Clone for PromptCachePlan

fn clone(&self) -> PromptCachePlan

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PromptCachePlan

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

Formats the value using the given formatter.

impl Default for PromptCachePlan

fn default() -> PromptCachePlan

Returns the “default value” for a type.