Struct Budget 

pub struct Budget {
    pub max_llm_calls: Option<u64>,
    pub max_elapsed_ms: Option<u64>,
    pub max_tokens: Option<u64>,
}

Session-level resource limits.

Extracted from ctx.budget at session start. When a limit is reached, alc.llm() raises a catchable Lua error ("budget_exceeded: ...") before sending the request to the host. The check happens at call-site, not after the LLM response arrives.

Budget is shared across the entire session — if alc.pipe() chains multiple strategies, they all draw from the same budget.

Fields

max_llm_calls: Option<u64>

Maximum number of LLM calls allowed in this session. Checked against SessionStatus::llm_calls (incremented in on_paused).

max_elapsed_ms: Option<u64>

Maximum wall-clock time (ms) allowed for this session. Measured from session start (Instant::now() at construction). Note: this is wall-clock, not CPU time. Includes time spent waiting for host LLM responses.

max_tokens: Option<u64>

Maximum total tokens (prompt + response) allowed in this session. Checked against accumulated prompt_tokens + response_tokens. Token counts may be estimated (±30%) or host-provided depending on TokenSource. Budget check uses whatever is available.

Implementations

impl Budget

pub fn from_ctx(ctx: &Value) -> Option<Self>

Extract budget from ctx JSON. Returns None if no budget field present.

pub fn check( &self, llm_calls: u64, elapsed_ms: u64, total_tokens: u64, ) -> Result<(), String>

Check if the session is within budget given current counters. Returns Err with a structured message if any limit is exceeded.

pub fn remaining_json( &self, llm_calls: u64, elapsed_ms: u64, total_tokens: u64, ) -> Value

Remaining budget as JSON given current counters. Returns { llm_calls: N|null, elapsed_ms: N|null, tokens: N|null }.

pub fn to_json(&self) -> Value

Serialize budget limits to JSON (for stats output).

Trait Implementations

impl Clone for Budget

fn clone(&self) -> Budget

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Budget

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

Formats the value using the given formatter.

impl Default for Budget

fn default() -> Budget

Returns the “default value” for a type.