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Performance Testing

Start Performance Test

Kick off a paced load test. Hitting this endpoint — not a flag on /api/initiatecall — is what tells the backend to treat the resulting calls as load-test traffic. The response returns immediately with a `perf_test_run_id`; the actual dialing happens in a background task.

POST
/api/performance-tests/start
Start Performance Test
curl --request POST \
  --url "https://agent-testing.lambdatest.com/api/performance-tests/start" \
  --header "Authorization: Basic <encoded-value>" \
  --header "Content-Type: application/json" \
  --data '{
    "project_id": "<project_id>",
    "source_suite_id": "<source_suite_id>",
    "concurrent_calls": 0,
    "scenario_ids": [],
    "scenarios": [],
    "suite_name": "<suite_name>",
    "profile": "<profile>",
    "max_concurrency": 0,
    "ramp_step_size": 0,
    "ramp_step_interval_seconds": 0,
    "sustained_duration_minutes": 0,
    "cooldown_between_calls_ms": 0
  }'
{
  "perf_test_run_id": "<string>",
  "suite_id": "<string>",
  "status": "running",
  "profile": "ramp_up",
  "max_concurrency": 123,
  "message": "<string>"
}

Authorizations

Authorizationstringheaderrequired

Basic authentication header of the form Basic <encoded-value>, where <encoded-value> is the base64-encoded string username:password.

Body

application/json
project_idstringrequired

Project ID to run the perf test against

source_suite_idstring

ID of the suite the test was launched from. When set, the orchestrator reads scenarios + matrix from this suite and ignores `scenario_ids / scenarios / iterations`.

concurrent_callsinteger

Total number of dials to place when `source_suite_id` is set. Distributed round-robin across the suite's combos at a fixed 5 calls-per-second pacing rate.

scenario_idsarray

Scenario IDs to expand and dial. Required when `source_suite_id` is not set.

scenariosarray

Per-scenario overrides (voice / phone number / matrix axes). Same shape used by /api/initiatecall — keeps matrix expansion behavior identical between live and load-test runs.

suite_namestring

Optional suite name for the auto-created perf suite. Defaults to `perf-test-{profile}-{run_id_prefix}` if unset.

profilestring

Pacing pattern: ramp_up | sustained | spike

max_concurrencyinteger

Peak concurrent calls the orchestrator is allowed to drive. The org's `max_inbound_parallel_calls` is temporarily raised to at least this value for the run, then restored.

ramp_step_sizeinteger

Calls added per ramp step (ramp_up profile only).

ramp_step_interval_secondsinteger

Seconds to wait between ramp steps before adding more load. Set to 0 when pacing is driven entirely by `cooldown_between_calls_ms` (e.g. when scheduling a fixed calls-per-second rate).

sustained_duration_minutesinteger

How long to hold max_concurrency once reached (sustained / spike).

cooldown_between_calls_msinteger

Milliseconds to stagger individual dials within a single step so provider create-call requests don't arrive simultaneously.

Response

application/json

Successful Response

perf_test_run_idstringrequired
suite_idstring
statusobject
profilestringrequired

Pacing pattern the orchestrator applies to the call list.

max_concurrencyintegerrequired
messagestringrequired
Start Performance Test
curl --request POST \
  --url "https://agent-testing.lambdatest.com/api/performance-tests/start" \
  --header "Authorization: Basic <encoded-value>" \
  --header "Content-Type: application/json" \
  --data '{
    "project_id": "<project_id>",
    "source_suite_id": "<source_suite_id>",
    "concurrent_calls": 0,
    "scenario_ids": [],
    "scenarios": [],
    "suite_name": "<suite_name>",
    "profile": "<profile>",
    "max_concurrency": 0,
    "ramp_step_size": 0,
    "ramp_step_interval_seconds": 0,
    "sustained_duration_minutes": 0,
    "cooldown_between_calls_ms": 0
  }'
{
  "perf_test_run_id": "<string>",
  "suite_id": "<string>",
  "status": "running",
  "profile": "ramp_up",
  "max_concurrency": 123,
  "message": "<string>"
}