Struct ProgressivePruner 

pub struct ProgressivePruner;

Progressive pruner for Tool output management.

Provides methods for soft trimming and hard clearing of content based on context usage thresholds.

Implementations

impl ProgressivePruner

pub fn soft_trim(content: &str, head_chars: usize, tail_chars: usize) -> String

Soft trim content by preserving head and tail, replacing middle with “…”.

Arguments

• content - The content to trim
• head_chars - Number of characters to preserve from the head
• tail_chars - Number of characters to preserve from the tail

Returns

The trimmed content string. If content is shorter than head_chars + tail_chars, returns the original content unchanged.

Example

let content = "A".repeat(2000);
let trimmed = ProgressivePruner::soft_trim(&content, 500, 300);
// Result: first 500 chars + "..." + last 300 chars

pub fn hard_clear(placeholder: &str) -> String

Hard clear content by replacing it entirely with a placeholder.

Arguments

• placeholder - The placeholder text to use

Returns

The placeholder string.

pub fn prune_messages( messages: &[Message], usage_ratio: f64, config: &PruningConfig, ) -> Vec<Message>

Prune messages based on context usage ratio.

This function applies progressive pruning to Tool outputs in messages based on the current context usage ratio and configuration.

Arguments

• messages - The messages to prune
• usage_ratio - Current context usage ratio (0.0-1.0)
• config - Pruning configuration

Returns

A new vector of messages with pruned Tool outputs.

pub fn is_tool_prunable(tool_name: &str, config: &PruningConfig) -> bool

Check if a tool is allowed to be pruned based on configuration.

Arguments

• tool_name - The name of the tool
• config - Pruning configuration

Returns

true if the tool can be pruned, false otherwise.