Runtime Control Value Registries

All multi-value fields in runtime control fixed metadata use the registries in this page. Values outside the listed standard ranges are invalid unless the field explicitly names a private/vendor range. Private/vendor values are not valid in mandatory conformance scenarios.

Receivers MUST reject fixed metadata that sets a reserved flag bit, uses a reserved enum value, or sets a reserved field to a non-zero value.

Role Codes

Value	Name	Meaning
0x00	unspecified	Only valid when the role field is optional.
0x01	client	Client-side SDK, caller, or browser endpoint.
0x02	server	Server-side SDK or service endpoint.
0x03	runtime	Runtime host or local execution engine.
0x04	subagent	Agent worker or delegated execution unit.
0x05	tool	Tool host or tool executor.
0x06	scheduler	Scheduler, router, or admission controller.
0x07	conformance_runner	Wire-level conformance runner.
0x08..0x7f	Reserved	Reserved for future standard role codes.
0x80..0xff	Private/vendor	Private extension range; excluded from conformance.

Reason And Stage Codes

Field	Value	Name	Meaning
reason_code	0x0000	unspecified	Generic reason.
reason_code	0x0001	user_cancelled	User or caller cancelled the work.
reason_code	0x0002	superseded	Replaced by a newer operation.
reason_code	0x0003	deadline_expired	Deadline or expiration timestamp passed.
reason_code	0x0004	budget_exceeded	Compute, memory, bandwidth, or token budget.
reason_code	0x0005	dependency_failed	Required dependency failed.
reason_code	0x0006	transport_closing	Transport is closing.
reason_code	0x0007	shutdown	Runtime or service shutdown.
reason_code	0x0008	conformance_injection	Injected by conformance runner.
drop_reason_code	0x0000	none	No drop reason.
drop_reason_code	0x0001	deadline_expired	Dropped after deadline.
drop_reason_code	0x0002	superseded	Dropped because a newer operation superseded.
drop_reason_code	0x0003	peer_cancelled	Dropped after peer cancellation.
drop_reason_code	0x0004	backpressure	Dropped due to pressure policy.
drop_reason_code	0x0005	capability_mismatch	Required capability was unavailable.
drop_reason_code	0x0006	budget_exceeded	Budget exceeded.
drop_reason_code	0x0007	object_invalidated	Referenced object was invalidated.
drop_reason_code	0x0008	transport_closed	Transport closed before result delivery.
drop_reason_code	0x0009	conformance_injection	Injected by conformance runner.
stage_code	0x0000	unspecified	Stage not specified.
stage_code	0x0001	queued	Accepted into a queue.
stage_code	0x0002	admitted	Admitted for execution.
stage_code	0x0003	input_received	Required input has arrived.
stage_code	0x0004	preprocessing	Pre-processing input.
stage_code	0x0005	executing	Main execution is running.
stage_code	0x0006	waiting_dependency	Waiting for dependency or upstream result.
stage_code	0x0007	producing_partial	Producing partial results.
stage_code	0x0008	finalizing	Finalizing output.
stage_code	0x0009	completed	Completed normally.
stage_code	0x000a	dropped	Result or operation was dropped.
stage_code	0x000b	failed	Execution failed.
Any listed field	0x000c..0x00ff	Reserved	Reserved for future standard values.
stage_code	0x0100..0x7fff	Profile-standard stages	Standard stages owned by a specific profile.
Any listed field	0x8000..0xffff	Private/vendor extension	Private extension range; excluded from tests.

Pressure, Cost, Route, Object, And Cache Codes

Field	Value	Name	Meaning
pressure_level	0x0000	none	No active pressure.
pressure_level	0x0001	soft	Sender should slow down.
pressure_level	0x0002	hard	Sender must stop or wait for credit.
pressure_level	0x0003	paused	Scope is paused until further notice.
pressure_reason	0x0000	unspecified	Generic pressure reason.
pressure_reason	0x0001	receiver_queue_full	Receiver queue is full.
pressure_reason	0x0002	sender_queue_full	Sender queue is full.
pressure_reason	0x0003	memory_pressure	Memory pressure.
pressure_reason	0x0004	bandwidth_pressure	Bandwidth pressure.
pressure_reason	0x0005	compute_pressure	Compute capacity pressure.
pressure_reason	0x0006	deadline_pressure	Deadline or freshness pressure.
pressure_reason	0x0007	fairness_policy	Fairness policy throttled the scope.
pressure_reason	0x0008	conformance_injection	Injected by conformance runner.
cost_model_id	0x0000	unspecified	Cost model not specified.
cost_model_id	0x0001	bytes_only	Cost entries are byte counts.
cost_model_id	0x0002	compute_units	Cost entries are compute units.
cost_model_id	0x0003	token_units	Cost entries are token units.
cost_model_id	0x0004	memory_bytes	Cost entries are memory byte budgets.
cost_model_id	0x0005	bandwidth_bytes	Cost entries are bandwidth byte budgets.
cost_model_id	0x0006	weighted_units	Cost entries use negotiated weighted units.
executor_class	0x0000	unspecified	Executor class not specified.
executor_class	0x0001	local_runtime	Local runtime executor.
executor_class	0x0002	remote_runtime	Remote runtime executor.
executor_class	0x0003	gpu_worker	GPU worker.
executor_class	0x0004	cpu_worker	CPU worker.
executor_class	0x0005	subagent	Agent worker.
executor_class	0x0006	tool_host	Tool host.
executor_class	0x0007	model_server	Model server.
executor_class	0x0008	render_worker	Render worker.
affinity_class	0x0000	none	No affinity requested.
affinity_class	0x0001	same_process	Prefer same process.
affinity_class	0x0002	same_host	Prefer same host.
affinity_class	0x0003	same_gpu	Prefer same GPU.
affinity_class	0x0004	same_numa	Prefer same NUMA node.
affinity_class	0x0005	same_region	Prefer same region.
affinity_class	0x0006	storage_local	Prefer local storage.
object_kind	0x0000	unspecified	Object kind not specified.
object_kind	0x0001	tensor	Tensor or tensor shard.
object_kind	0x0002	token_block	Token block.
object_kind	0x0003	image_tile	Image or render tile.
object_kind	0x0004	feature_map	Feature map.
object_kind	0x0005	tool_result	Tool result artifact.
object_kind	0x0006	trace_segment	Trace segment artifact.
object_kind	0x0007	opaque_bytes	Opaque byte object.
object_kind	0x0008	document_chunk	Document chunk.
object_kind	0x0009	audio_chunk	Audio chunk.
object_kind	0x000a	video_chunk	Video chunk.
object_kind	0x000b	route_plan	Route plan artifact.
object_kind	0x000c	cache_manifest	Cache manifest artifact.
memory_location_hint	0x0000	unspecified	Location not specified.
memory_location_hint	0x0001	host_memory	Host memory.
memory_location_hint	0x0002	device_memory	Device memory.
memory_location_hint	0x0003	shared_memory	Shared memory.
memory_location_hint	0x0004	remote_memory	Remote memory.
memory_location_hint	0x0005	mmap_file	Memory-mapped file.
memory_location_hint	0x0006	object_store	External object store.
ownership_hint	0x0000	unspecified	Ownership not specified.
ownership_hint	0x0001	producer_owned	Producer retains ownership.
ownership_hint	0x0002	consumer_owned	Consumer takes ownership.
ownership_hint	0x0003	session_owned	Session owns object lifecycle.
ownership_hint	0x0004	borrowed	Borrowed reference.
ownership_hint	0x0005	transfer_on_ref	Ownership transfers on reference.
ownership_hint	0x0006	release_on_drop	Release when result is dropped.
release_reason	0x0000	completed	Normal release after completion.
release_reason	0x0001	cancelled	Released after cancellation.
release_reason	0x0002	expired	Released after expiration.
release_reason	0x0003	replaced	Released because replaced.
release_reason	0x0004	invalidated	Released due to invalidation.
release_reason	0x0005	owner_closed	Owner closed.
release_reason	0x0006	lease_expired	Lease expired.
release_reason	0x0007	conformance_injection	Injected by conformance runner.
reuse_scope	0x0000	operation	Reuse within one operation.
reuse_scope	0x0001	session	Reuse within one session.
reuse_scope	0x0002	connection	Reuse within one connection.
reuse_scope	0x0003	global	Reuse across connections.
reuse_scope	0x0004	tenant	Reuse within one tenant.
reuse_scope	0x0005	profile	Reuse within one profile namespace.
miss_reason	0x0000	unknown	Unknown miss reason.
miss_reason	0x0001	not_found	Cache key was not found.
miss_reason	0x0002	expired	Entry expired.
miss_reason	0x0003	invalidated	Entry was invalidated.
miss_reason	0x0004	schema_mismatch	Entry schema or profile did not match.
miss_reason	0x0005	producer_unavailable	Producer or owner is unavailable.
miss_reason	0x0006	lease_required	Lease was required but missing.
miss_reason	0x0007	permission_denied	Access denied.
Any listed field	First unused..0x7fff	Reserved	Reserved for future standard values.
Any listed field	0x8000..0xffff	Private/vendor extension	Private extension range; excluded from tests.

Flag Masks

Metadata layout	Field	Valid mask	Defined bits
Control Request Metadata	flags	0x03	bit 0: cooperative allowed; bit 1: hard abort allowed.
Scheduling Metadata	flags	0x00000003	bit 0: discard stale work; bit 1: emit drop reason.
Supersede Metadata	flags	0x0001	bit 0: abort old operation immediately.
Budget Metadata	flags	0x00000003	bit 0: replace; bit 1: increment.
Partial Result Metadata	flags	0x00000003	bit 0: final partial; bit 1: object ref present.
Pressure Metadata	flags	0x00000003	bit 0: applies to connection; bit 1: applies to operation.
Capability Metadata	flags	0x00000003	bit 0: hard requirement; bit 1: downgrade allowed.
Route Hint Metadata	flags	0x00000003	bit 0: must honor; bit 1: best effort.
Trace Context Metadata	flags	0x0003	bit 0: sampled; bit 1: error.
Result Drop Metadata	flags	0x03	bit 0: final; bit 1: retryable.
Recoverable Error Metadata	flags	0x03	bit 0: retryable now; bit 1: retry after required.
Retry After Metadata	flags	0x03	bit 0: applies to connection; bit 1: applies to operation.
Object Reference Metadata	flags	0x00000007	bit 0: borrowed; bit 1: mutable; bit 2: region present.
Object Release Metadata	flags	0x03	bit 0: final release; bit 1: invalidates dependents.
Object Delta Metadata	flags	0x00000007	bit 0: replaces region; bit 1: compressed; bit 2: final delta.
Cache Reference Metadata	flags	0x00000003	bit 0: lease required; bit 1: body fallback present.