Extension Fields ◈︎

AIOSchema Official Extension Fields

Version: v0.5.6 Spec reference: Specification §11 Full registry: /registries/extensions/

Extension fields are placed in the extensions block of a manifest. They are optional unless the conformance level or regulatory context requires them. They are outside the core_fingerprint computation. When manifest_signature is present, all extensions are within its signature scope.

The total serialized size of extensions MUST NOT exceed 4KB.

Media Capture Fields

Field	Type	Description
`camera_model`	String	Device make and model (e.g. `"Canon EOS R5"`)
`exposure_time`	String	Shutter speed (e.g. `"1/120"`)
`iso`	Integer	ISO sensitivity value
`software`	String	Software used to create or edit the asset

Asset Classification Fields

Field	Type	Description
`asset_name`	String	Original filename or human-readable asset name
`asset_type`	String	Asset type: `"document"`, `"image"`, `"video"`, or similar
`description`	String (max 256 chars)	Human-readable provenance context note. MUST NOT be used for machine-parseable metadata, rights declarations, or version history.
`license`	String	SPDX identifier (e.g. `"CC-BY-4.0"`)

AI Disclosure Fields

`ai_model_used`

Property	Value
Type	String or null
null	Asset is not AI-generated

AI model identifier string, or null when the asset has no AI involvement.

`ai_model_version`

Property	Value
Type	String or null

Version string of the AI model used, or null.

`ai_declaration`

Structured boolean record of AI involvement. When disclosure_required is true, all fields MUST accurately reflect the actual nature of AI involvement.

Field	Type	Requirement	Description
`disclosure_required`	Boolean	MUST	True if AI contributed to this content
`ai_generated`	Boolean	MUST	Content is fully AI-generated
`ai_manipulated`	Boolean	MUST	Existing content was substantially altered by AI
`human_reviewed`	Boolean	MUST	A human reviewed the content before publication
`standard_editing`	Boolean	OPTIONAL	Only standard editing applied (cropping, colour correction, noise removal). When true, `disclosure_required` MUST be false.
`creative_work`	Boolean	OPTIONAL	Artistic, satirical, or fictional work.

When human_reviewed is true, compliance_eu_art50 SHOULD be present.

"ai_declaration": {
  "disclosure_required": true,
  "ai_generated": true,
  "ai_manipulated": false,
  "human_reviewed": true,
  "standard_editing": false,
  "creative_work": false
}

Soft Binding

`soft_binding`

Perceptual hash record for image and video assets. MUST be present at Level 2 for image and video assets.

Field	Type	Description
`algorithm`	String	Perceptual hash algorithm. Currently: `pHash-v1`
`fingerprint`	String	16-character hex pHash digest
`threshold_info`	Integer	Informational only. Verifiers MUST NOT use this value for policy decisions.

"soft_binding": {
  "algorithm": "pHash-v1",
  "fingerprint": "f8e4c2a196b3d750",
  "threshold_info": 5
}

Conformance

`compliance_level`

Self-declared conformance level: 1, 2, or 3. Informational only. Not to be confused with compliance_eu_art50.

Regulatory Compliance Fields

`compliance_eu_art50`

Records that a qualifying editorial review occurred under EU AI Act Art. 50(4). Two fields are required when claiming the editorial exemption.

Field	Type	Required for exemption	Description
`editorial_responsibility`	String	MUST	Organisation name or role title of the person holding editorial responsibility. Not a personal name.
`review_type`	String (enum)	MUST	`"substantive"` or `"editorial-control"`
`reviewer_id`	String	OPTIONAL	Ed25519 public key fingerprint (`ed25519-fp-<32hex>`). Non-identifying.

"compliance_eu_art50": {
  "editorial_responsibility": "Editorial Team, Example Media Ltd",
  "review_type": "substantive"
}

Verification Field

`public_key`

Base64-encoded raw 32-byte Ed25519 public key. Enables self-contained verification without network access.

When present, the verifier MUST perform a fingerprint cross-check against creator_id:

Decode the Base64 value to raw bytes.
Compute SHA-256 and take the first 16 bytes (32 hex characters).
Construct ed25519-fp-<32hex> and compare against creator_id using timing-safe equality.
If mismatch: FAIL. If match: proceed with signature verification.

"public_key": "MCowBQYDK2VwAyEAj4VZRK5VJThKGx8LYXeF8YvjNWKpWnLqM3rXeV4Q9sM="

Vendor Extensions

Vendor-specific fields use registered prefixes. See Registry Governance and Extension Registry.