Struct CompactState 

pub struct CompactState {

    pub last_input_tokens: Option<u64>,
    pub last_output_tokens: Option<u64>,
    pub estimated_unsent_bytes: usize,
    pub context_window: u64,
    pub total_tokens_before_compaction: u64,
    pub compaction_count: u32,
    pub auto_compact_threshold_percent: u8,
    pub consecutive_failures: u32,
    pub summary: Option<String>,
    pub summary_message_count: usize,
    pub rebuild_context: Option<String>,
    pub crossed_thresholds: Vec<f64>,
    pub history_synced_message_keys: HashSet<u64>,
}

Tracks token usage and compact failure state for autocompact decisions.

Measurement model (aligned with modern coding CLI TUI):

• context tokens used = last API input_tokens (ground truth for the current context) + client preflight for unsent bytes (bytes/4)
• window = model context_window from registry
• usage % = used / window
• total before compaction = cumulative input tokens across turns (historical; does not reset when the bar drops after compact)

Fields

last_input_tokens: Option<u64>

Token count from the last model response usage (current context size).

last_output_tokens: Option<u64>

Output tokens from the last model response (UI turn label).

estimated_unsent_bytes: usize

Estimated bytes of new messages not yet sent to the model.

context_window: u64

Context window size in tokens for the current model.

total_tokens_before_compaction: u64

Cumulative input tokens processed before/during compaction cycles.

compaction_count: u32

Number of compaction runs in this session.

auto_compact_threshold_percent: u8

Auto-compact when context_percentage >= this (default: 85).

consecutive_failures: u32

Number of consecutive compact failures.

summary: Option<String>

summary_message_count: usize

rebuild_context: Option<String>

Latest long-horizon rebuild context that must stay attached to the system prompt across subsequent turns.

crossed_thresholds: Vec<f64>

List of checkpoint thresholds crossed in the current context cycle.

history_synced_message_keys: HashSet<u64>

Fingerprints of messages already copied into long-horizon history.

Implementations

impl CompactState

pub fn new(context_window: u64) -> Self

pub fn add_unsent_bytes(&mut self, bytes: usize)

pub fn clear_unsent_bytes(&mut self)

pub fn context_tokens_used(&self, pending_input_bytes: usize) -> u64

Current context size (live context usage).

pub fn context_window_tokens(&self) -> u64

Context window size (context window size).

pub fn context_window_usage(&self, pending_input_bytes: usize) -> u8

Integer percent of the window in use (context window usage percent).

pub fn total_estimated_tokens(&self, pending_input_bytes: usize) -> u64

Estimate tokens for the next request: API last-input (server) + unsent/pending client bytes as ceil(bytes/4).

pub fn threshold_level(&self, pending_input_bytes: usize) -> CompactThreshold

pub fn should_autocompact(&self, buffer_tokens: u64) -> bool

pub fn context_percentage(&self, pending_input_bytes: usize) -> u8

pub fn usage_label(&self, pending_input_bytes: usize) -> String

Compact context meter for the composer footer: 3.2k / 200k. Percentage is revealed on hover (see usage_label_with_percent).

pub fn usage_label_compact(&self, pending_input_bytes: usize) -> String

Token counts only — default (non-hover) display.

pub fn usage_label_with_percent(&self, pending_input_bytes: usize) -> String

Token counts + percent — shown while the context chip is hovered.

pub fn update_usage(&mut self, input_tokens: u64)

Record provider usage for this turn (called every stream that reports usage).

pub fn update_usage_full(&mut self, input_tokens: u64, output_tokens: u64)

Record full turn usage and refresh live context metrics.

pub fn turn_usage_label(&self) -> Option<String>

Label shown in the TUI footer — updates every turn after update_usage*.

pub async fn auto_compact( &mut self, messages: &mut Vec<ModelMessage>, model_provider: &dyn ModelProvider, model_name: &str, harness_config: &HarnessConfig, ) -> Result<Option<CompactOutcome>>

pub async fn force_compact( &mut self, messages: &mut Vec<ModelMessage>, model_provider: &dyn ModelProvider, model_name: &str, harness_config: &HarnessConfig, ) -> Result<Option<CompactOutcome>>

Force compaction with the session model even when below the threshold. Manual Compact always fully replaces conversation history (keep_ratio=0).

pub fn apply_manual_summary( &mut self, messages: &mut Vec<ModelMessage>, summary: String, ) -> CompactOutcome

Trait Implementations

impl Clone for CompactState

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 CompactState

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

Formats the value using the given formatter.

impl Default for CompactState

fn default() -> Self

Returns the “default value” for a type.