Struct ExternalMetricsOutput 

pub struct ExternalMetricsOutput {
    pub framework: String,
    pub cold_start_us: u64,
    pub first_llm_call_epoch_ns: u64,
    pub loop_overhead: ExternalDurationStats,
    pub peak_rss_bytes: Option<u64>,
    pub throughput_agents_per_sec: Option<f64>,
    pub token_overhead: Option<ExternalTokenOverhead>,
}

External Benchmark Protocol (EBP) — the JSON schema that all external framework benchmark scripts MUST emit on stdout.

This is the contract between adk-bench and any competitor framework harness. External scripts receive: the workload JSON path as last CLI arg, and BENCH_START_EPOCH_NS in their environment (monotonic nanosecond timestamp at subprocess spawn time).

They MUST output exactly one JSON object (no other stdout content):

{
  "framework": "langgraph",
  "cold_start_us": 45000,
  "first_llm_call_epoch_ns": 1705312800000045000,
  "loop_overhead": {
    "min_us": 120, "max_us": 890, "mean_us": 340,
    "median_us": 310, "p95_us": 780, "p99_us": 870, "count": 10
  },
  "throughput_agents_per_sec": 12.5,
  "peak_rss_bytes": 52428800,
  "token_overhead": {
    "total_tokens": 1200, "user_content_tokens": 950, "overhead_tokens": 250
  }
}

Fields

framework: String

Framework name (e.g., “adk-python”, “langgraph”, “crewai”).

cold_start_us: u64

Cold start time in microseconds (subprocess spawn → first LLM call).

first_llm_call_epoch_ns: u64

Monotonic nanosecond timestamp when the first LLM call was made. Used with BENCH_START_EPOCH_NS to compute cold start from the external clock.

loop_overhead: ExternalDurationStats

Per-turn framework overhead statistics (LLM time subtracted).

peak_rss_bytes: Option<u64>

Peak RSS in bytes (null if platform doesn’t support measurement).

throughput_agents_per_sec: Option<f64>

Agents completed per second at the requested concurrency (null if not measured).

token_overhead: Option<ExternalTokenOverhead>

Token overhead breakdown (null if not measured).

Trait Implementations

impl Clone for ExternalMetricsOutput

fn clone(&self) -> ExternalMetricsOutput

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExternalMetricsOutput

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ExternalMetricsOutput

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for ExternalMetricsOutput

fn eq(&self, other: &ExternalMetricsOutput) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for ExternalMetricsOutput

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ExternalMetricsOutput