Track

Source file	schemas/track.schema.json
$id	https://synapsecommand.local/cdm/1.0.0/track.schema.json
CDM schema version	1.0.0
SHA-256 of source	28e44c85743e9b497e0376918bdace4b054554b194fd7ec6e8e4cdea142541f7

An entity's position history, in time order. The order is a contract, not a hope.

A scrambled sample list produces nonsense the moment anything differentiates it — speed from consecutive positions, a heading arrow, a predicted point. So non-decreasing timestamps are validated here, at the boundary, where the defect is one adapter's bug rather than a mystery in a fusion layer three hops downstream.

Equal timestamps are ALLOWED: two sensors reporting the same instant is real, and rejecting it would refuse legitimate multi-source data.

Fields

Field	Type	Required	Description
entity_id	string (uuid)	yes	The Entity this history belongs to.
integrity	Integrity | null	no	PQC signature block — designed, not yet populated. Default null.
object_kind	"track"	no
samples	array<TrackSample>	yes	Time-ordered, non-decreasing. At least one. (min items 1)
schema_version	string	no	Semver of the CDM this object was written against. Default "1.0.0".
source	SourceRef	yes	Which adapter produced this object. Required on every kind.
source_ids	array<SourceId>	yes	Every external identifier this object is known by. At least one, on EVERY kind — see the class docstring. (min items 1)
track_id	string (uuid)	yes
track_quality	number | null	no	0..1. None = not assessed, never 0. Default null. (≥ 0; ≤ 1)

:::info additionalProperties: false Unknown keys are rejected. That is safe only because the CDM pairs strictness with a declared escape hatch — Entity.attributes and Event.payload accept anything — so an adapter never has to choose between dropping a field and failing validation. :::

Referenced definitions

Every $ref on this page resolves to one of these, inlined here so the page is a complete reference and not a starting point for chasing pointers.

Integrity

DESIGNED, NOT IMPLEMENTED — the field the PQC signature will occupy.

No crypto happens in this package (tests/test_cdm_boundary.py asserts the package imports no crypto module). The field exists from day one so that turning signing on is a value change rather than a schema change: a schema change would be a MAJOR bump rippling through every store and every consumer, and would arrive exactly when the signing work is already late.

algorithm is a free string rather than an enum, naming what the platform's ledger already uses — ML-DSA-87 for entry signatures, SLH-DSA for checkpoints. Free, because the algorithm that replaces those is not knowable now, and an enum would make the migration a MAJOR bump for a value nobody reasons over programmatically.

All three fields or none. A block holding a signature with no algorithm is unverifiable, and an unverifiable signature that LOOKS present is worse than an absent one: it reads as assurance to everything downstream that does not check.

Field	Type	Required	Description
algorithm	string	yes	e.g. ML-DSA-87, SLH-DSA-SHAKE-256s. (min length 1)
chain_hash	string	yes	Hash binding this object to the chain. (min length 1)
signature	string	yes	(min length 1)

additionalProperties: false — unknown keys are rejected. Source-specific fields belong in the declared extension bags (Entity.attributes, Event.payload).

Position

A fix. Both coordinates required — that is how the null-never-zero rule is structural.

An unknown position is the ABSENCE of this object (entity.position is None), never a Position holding zeros. Because lat and lon are required here, an adapter cannot express "unknown" as (0, 0) even by accident: it has to either omit the Position or state a real coordinate. Coordinate zero is a real point in the Gulf of Guinea, and a contact painted there is a contact that does not exist.

accuracy_m absent means unknown accuracy, NOT perfect accuracy. Zero would mean a fix with no error, which no sensor produces.

Field	Type	Required	Description
accuracy_m	number | null	no	Metres, 1-sigma. None = unknown, never 0. Default null. (≥ 0)
alt_m	number | null	no	Metres HAE. None = unknown. Default null.
lat	number	yes	WGS84 decimal degrees. (≥ -90; ≤ 90)
lon	number	yes	WGS84 decimal degrees. (≥ -180; ≤ 180)
position_source	PositionSource	yes	How the fix was obtained — the field that survives GNSS denial.

additionalProperties: false — unknown keys are rejected. Source-specific fields belong in the declared extension bags (Entity.attributes, Event.payload).

PositionSource

How the position was obtained. Load-bearing in a GNSS-denied environment.

This is the field that lets a commander tell a fix from a guess. When PNTMAP reports jamming over an area, every GNSS-sourced position inside that area becomes suspect and every INERTIAL or MANUAL one does not — a distinction that is impossible to make after the fact if the adapter flattened them all to "position".

Closed vocabulary — a value outside this list is invalid, and UNKNOWN is a

member rather than a null wherever the enum has one.

Value
GNSS
INERTIAL
MANUAL
ESTIMATED

SourceId

One external identifier for an object — the provenance mapping.

A list of these, not one, because the same object arrives from several systems: the same vessel is an MMSI to AIS, a track number to STANAG 4676 and a UID to TAK. Fusion joins them later; the adapter's job is to record which name its own system used, and never to overwrite another system's entry.

Field	Type	Required	Description
external_id	string	yes	That system's own identifier. (min length 1)
system	string	yes	The external system, e.g. PNTMAP, TAK. (min length 1)

additionalProperties: false — unknown keys are rejected. Source-specific fields belong in the declared extension bags (Entity.attributes, Event.payload).

SourceRef

Which adapter produced this object, from which system, and whether it is real.

synthetic is required and has no default. Every fixture in this repository is synthetic and every scenario package is too (TR-12), and the platform keeps the synthetic and live layers apart over one interface — so an object that does not say which layer it belongs to cannot be filed. A default of false would silently promote exercise data to operational data, which is the dangerous direction; a default of true would silently demote live data and hide it from an operator. There is no safe default, so there is no default.

Field	Type	Required	Description
adapter	string	yes	Adapter name, e.g. pntmap. (min length 1)
adapter_version	string	yes	Adapter semver. (min length 1)
synthetic	boolean	yes	true for anything not from a real source (TR-12).
system	string	yes	The external system this came from. (min length 1)

additionalProperties: false — unknown keys are rejected. Source-specific fields belong in the declared extension bags (Entity.attributes, Event.payload).

TrackSample

One position at one instant. The unit STANAG 4676 calls a track point.

Field	Type	Required	Description
observed_at	string	yes	RFC 3339 UTC, exactly three decimal places, always Z. (pattern ^[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}:[0-9]{2}\.[0-9]{3}Z$)
position	Position	yes

additionalProperties: false — unknown keys are rejected. Source-specific fields belong in the declared extension bags (Entity.attributes, Event.payload).