generated: '2026-07-20'
method: derived
source: >-
  https://raw.githubusercontent.com/ultraleap/leapc-python-bindings/main/leapc-python-api/src/leap/
  + https://docs.ultraleap.com/api-reference/tracking-api/leapc-guide.html
notes: >-
  LeapC is a native C API using local IPC to the Ultraleap Hand Tracking Service,
  not an HTTP API. The cross-cutting semantics below are the native equivalents of
  the usual web conventions. There is NO idempotency-key contract, NO cursor/offset
  pagination, NO HTTP request-id header and NO OAuth — those web conventions do not
  apply to a polled local message stream, and are recorded here as not-applicable
  rather than fabricated. The dominant convention is the connection + poll-loop
  (message pump) model.
transport:
  style: native-c-ipc
  detail: LeapC client opens a LEAP_CONNECTION to the local Hand Tracking Service; no network base URL.
authentication:
  style: none
  detail: Access is local process-to-service IPC; there is no API key, token or OAuth surface.
delivery_model:
  style: poll-loop
  detail: >-
    LeapPollConnection() drives a message pump that returns LEAP_CONNECTION_MESSAGE
    events (tracking, device, policy, config, image, log). Callers dispatch on the
    EventType discriminator. This replaces request/response for streamed data.
  concurrency: >-
    LeapPollConnection must not be called concurrently from multiple threads
    (eLeapRS_ConcurrentPoll); serialize the poll loop.
frames:
  identity: LEAP_TRACKING_EVENT carries tracking_frame_id and a timestamp (microseconds, LeapC clock).
  interpolation: LeapInterpolateFrame()/LeapGetFrameSize() allow resampling a frame to a requested timestamp.
  clock: LeapGetNow() returns the current LeapC timestamp for synchronizing to a target rendering clock.
idempotency:
  supported: false
  detail: Not applicable — streamed tracking frames are read-only samples, not mutating requests.
pagination:
  supported: false
  detail: Not applicable — tracking data is a continuous polled stream, not a paged collection.
error_model:
  style: native-enum
  detail: Every LeapC function returns an eLeapRS result; eLeapRS_Success is 0, all others are errors. See errors/leap-motion-error-codes.yml.
configuration:
  policy_flags: LeapSetPolicyFlags() sets tracking policies (e.g. images, optimize-for-HMD, map-points).
  tracking_mode: LeapSetTrackingMode() selects desktop / screentop / HMD tracking modes.
versioning:
  detail: See lifecycle/leap-motion-lifecycle.yml — SDK/service versioning, Orion V4 to Gemini V5 migration.
cross_links:
  errors: errors/leap-motion-error-codes.yml
  data_model: data-model/leap-motion-data-model.yml
  lifecycle: lifecycle/leap-motion-lifecycle.yml
  conformance: conformance/leap-motion-conformance.yml