META
Metadata Enrichment Engines
1. Identity
| Attribute | Value |
|---|---|
| Type code | META |
| Canonical name | Metadata Enrichment Engines |
| Parent type | — |
| Type status | review |
| Tier scope | tier-0, tier-2, tier-3 |
| Invocation | chained |
| Payload effect | annotate |
| Lineage role | stamps-cmi |
META is a category boundary, not an identity. Members are identified by MEID, versioned through ZAR as CMIs, and carry mice.category: META. The type itself has no MEID, no CMI and no runtime presence.
2. Purpose and boundary
Metadata Enrichment Engines (META) are Micro Engines responsible for attaching semantic, taxonomic, and governance metadata to data signals.
META engines do not compute, transform, or aggregate numeric values.
They enrich signals with meaning and context, enabling:
- regulatory interpretation,
- explainability,
- policy reasoning,
- federation discovery.
Design rationale
Separating metadata enrichment into a dedicated engine type ensures:
- semantic clarity between values and meaning,
- reusable, composable regulatory mappings,
- auditable explanation of why a signal is treated a certain way,
- federation-safe discovery without coupling logic.
Metadata is not decoration — it is machine-readable meaning, and META engines make it explicit.
3. Membership criteria
3.1 Inclusion tests
A micro engine is a member of META when its specification satisfies the following:
META engines attach or derive non-numeric meaning, including:
- Regulatory tags (e.g. ESRS-E1, ESRS-E5, EU-Taxonomy)
- Domain and scope annotations (e.g.
scope:3,category:travel) - Materiality or relevance indicators
- Jurisdictional or framework context
- Disclosure readiness or completeness flags
META engines may also:
- normalize tag vocabularies,
- map free-form labels to canonical taxonomies,
- enrich signals for federation discovery.
Tagging engines are a subset of META engines.
3.2 Exclusions
A micro engine is not a member of META when any of the following is its responsibility; each belongs to the type named:
- ❌ Primary computation (CALC)
- ❌ Validation or constraint checking (VALI)
- ❌ Unit or format conversion (TRFM)
- ❌ Aggregation or roll-ups (AGGR)
- ❌ Estimation or extrapolation (SEM)
- ❌ Policy enforcement or routing (ZSSR)
META engines describe signals — they do not decide or compute.
3.3 Boundary cases
- META versus RMAP: META attaches taxonomy and context; RMAP maps a signal into a risk framework (category, band, severity). A framework tag is META; a risk band is RMAP.
- META versus TRFM: metadata that sits beside an unchanged payload is META; a change to the payload itself is TRFM.
- META versus GEOX: a location-derived attribute resolved from geometry is GEOX; a jurisdiction tag taken from existing metadata is META.
4. Design rules
META engines SHALL NOT alter quantitative values.
All enrichment is driven by explicit taxonomies, ontologies, or controlled mappings.
Metadata can be layered incrementally without invalidating prior enrichments.
Every enrichment action leaves a lineage record explaining what was added and why.
5. Contract
5.1 Inputs
META engines consume:
- Validated signals or computation outputs
- Taxonomy, ontology, or registry references
- Contextual parameters, such as:
- jurisdiction
- reporting framework
- scope or boundary definitions
Inputs SHALL be semantically valid, but need not be numerically complete.
5.2 Outputs
META engines produce:
- The original signal payload (unchanged)
- Attached metadata annotations
- Enrichment provenance, including:
- enrichment rule or mapping reference
- engine version
- execution context
META outputs are commonly consumed by:
- reporting and disclosure pipelines,
- explainability layers (ZARA),
- routing and orchestration (ZSSR),
- federation and partner discovery.
6. Position in the computation chain
6.1 Placement
META engines can operate at multiple points in a pipeline:
INPUT
→ VALI
→ CALC
→ TRFM
→ AGGR
→ META
→ Reporting / Disclosure / Assurance
They may also run:
- immediately after CALC (to tag scope or category),
- after AGGR (to tag disclosure-level outputs),
- independently as contextual enrichment.
7. Identity rules for members
Members are micro engines (CMPS-001 mice: block) whose identity satisfies all of the following:
mice.categorySHALL beMETA.- The
CAPABILITYsegment of the MEID (MEID_<DOMAIN>_<CAPABILITY>_<FUNCTION>) SHALL be one ofENRICH,CLASSIFY. - The
DOMAINsegment SHALL be any registered MEID domain. - Typical
FUNCTIONsegments:ENRICHER,CLASSIFIER. - CMI kinds bound through
zar.meid_cmi_bindingSHALL be amongENGINE. - Lineage: members append their CMI stamp to the USO lineage tail.
- Tier scope: tier-0, tier-2, tier-3; invocation: chained; payload effect: annotate.
- USO role: attaches semantic context to signals
META identifiers appear in:
- signal lineage (CMI stamps),
- registry metadata,
- explainability surfaces.
10. Members
11. Related types
- CALC — Calculation Engines
- AGGR — Aggregation Engines
- EXTR — Extraction Engines
- NORM — Normalization Engines
- RMAP — Risk Mapping Engines
- SCEN — Scenario Engines
- SCORE — Scoring Engines
- AME — Assurance / Meta engines
- VALI — Validator Engines
- TRFM — Transformation Engines
Other related documents
- ZARA — Explainability & reasoning