Validate material sample annotations against ontology constraints — check that class names and property names exist in the ontology, verify domain and range consistency for object property relationships, assess annotation completeness (required, recommended, and optional properties), and flag unknown or misspelled terms. Use when verifying that CMSO or other ontology annotations are correct before publishing, checking whether all required properties are present for a class like Crystal Structure or Unit Cell, auditing relationship triples between instances, or catching annotation errors early in a FAIR data workflow, even if the user only says "is my annotation correct" or "what am I missing."
Validate that material sample annotations comply with ontology constraints: correct class names, valid properties, consistent domain/range relationships, and required fields present.
Requirements
Python 3.10+
No external dependencies (Python standard library only)
Requires ontology-explorer's cmso_summary.json and ontology_registry.json
What do you need to validate?
├── An annotation (classes and properties are correct)
│ └── schema_checker.py --ontology cmso --annotation '<json>'
├── Completeness of a class annotation
│ └── completeness_checker.py --ontology cmso --class <name> --provided <props>
└── Object property relationships
└── relationship_checker.py --ontology cmso --relationships '<json>'
Script Outputs (JSON Fields)
Script
Key Outputs
scripts/schema_checker.py
results.valid, results.errors (each unknown_class/unknown_property error carries a suggestions array of nearest matches), results.warnings, results.class_valid, results.properties_valid
After mapping a sample with ontology-mapper, pass the annotations to schema_checker.py to verify correctness.
For a specific class, use completeness_checker.py to see what required/recommended properties are missing.
When building relationships between instances, use relationship_checker.py to ensure domain/range consistency.
Conversational Workflow Example
User: I annotated my sample as CrystalStructure with properties hasUnitCell and hasBasis.
Is this correct and complete?
Agent: Let me both validate the annotation and check its completeness.
[Runs: schema_checker.py --ontology cmso --annotation
'{"class":"Crystal Structure","properties":{"has unit cell":true,"has basis":true}}' --json]
[Runs: completeness_checker.py --ontology cmso --class "Crystal Structure"
--provided "has unit cell,has basis" --json]
From schema_checker.py (results.warnings):
- has unit cell: valid for Crystal Structure
- has basis: domain_mismatch warning — its domain is "Unit Cell", not
Crystal Structure (so this property belongs on the Unit Cell instance)
From completeness_checker.py (results, completeness_score = 0.5):
- **required_missing**: has space group
So: add "has space group" to the Crystal Structure annotation, and move
"has basis" onto the Unit Cell annotation. (The domain insight comes from
schema_checker.py's warnings; completeness_checker.py only reports the
missing required "has space group".)
Apply the nearest-match suggestions from the error, or use ontology-explorer to find the correct name
Property 'X' not found ... (did you mean 'Y'?)
Invalid/misspelled property name
Apply the nearest-match suggestions from the error, or use property_lookup.py to search
Annotation must be a dict
Wrong input format
Provide valid JSON dict
Relationships must be a non-empty list
Wrong input format
Provide JSON array of relationship dicts
Interpretation Guidance
Errors indicate definite problems (unknown class/property, range mismatch)
Warnings indicate potential issues (domain mismatch — may be intentional for subclasses)
Completeness score: 0.0-1.0 ratio of provided vs. total tracked
properties. It weights required, recommended, and optional properties
equally, so a moderate score (e.g. 0.5-0.67) can coexist with missing
required properties. ALWAYS check required_missing first: a non-empty
required_missing means the annotation is invalid regardless of the score.
required_missing: must fix for valid annotation
recommended_missing: should fix for quality
unrecognized: may indicate typos or properties from a different ontology
Verification checklist
Ran schema_checker.py --json and recorded results.valid; confirmed results.errors is an empty array (a valid:true with any unknown_class/unknown_property error cannot occur, but confirm the array length is 0 rather than trusting the boolean alone).
For every domain_mismatch entry in results.warnings, recorded the property, its reported domain, and the class it was applied to, then made an explicit keep-or-move decision (warnings are not auto-fixed and may be intentional for a subclass).
Ran completeness_checker.py --json and confirmed results.required_missing is empty BEFORE quoting completeness_score — a non-empty required_missing means the annotation is invalid no matter how high the score is.
Recorded the exact completeness_score together with the required_missing, recommended_missing, and optional_missing lists (do not paraphrase the score as "complete" while any required item is missing).
For each unknown class/property error, recorded the suggestions[0] value and confirmed the corrected name actually exists in the ontology (re-ran the checker, or checked via ontology-explorer) rather than assuming the top suggestion is right.
Ran relationship_checker.py --json for every subject-property-object triple and confirmed each per-triple results.results[i].valid is true; recorded any results.errors strings naming the offending domain or range.
Confirmed the --ontology used (e.g. cmso, asmo) matches the ontology the annotation was authored against — a class can be "unknown" simply because the wrong constraints/summary file was loaded.
Common pitfalls & rationalizations
Tempting shortcut
Why it's wrong / what to do
"completeness_score is 0.67, so the annotation is basically complete."
The score weights required, recommended, and optional tiers equally, so a high score can still hide a missing required property. Check required_missing first; a non-empty list means invalid regardless of score.
"schema_checker returned only warnings, no errors, so I'll ignore them."
domain_mismatch warnings flag a property attached to a class that is not (a subclass of) its domain — often the property belongs on a different instance. Record each warning and decide explicitly; don't auto-dismiss.
"The class name didn't match but the validator gave a suggestion, so I'll just use it."
suggestions come from stdlib difflib fuzzy matching (cutoff 0.6) and can be wrong or empty. Verify the suggested name exists in the ontology before applying it.
"Two of the three relationships passed, so the triples are fine."
results.valid is the AND over all triples; you must inspect each results.results[i] and its errors. A single failing domain/range check invalidates the relationship set.
"It returned valid:true, so the annotation is semantically correct."
The checker only verifies class/property existence and domain/range against a manually curated constraints file. It does not check data types, cardinality, or value plausibility — valid:true is necessary, not sufficient.
"Property exists in the ontology, so it applies to my class."
Existence is checked against the full property set; domain applicability is a separate subclass-aware check. A real property can still trigger a domain_mismatch warning on the wrong class.
"I'll trust the bare class name; substrings are close enough."
Domain/subclass matching is exact-equality plus parent traversal, NOT substring containment. Material is not credited with Crystalline Material properties; use the precise ontology class name.
Security
Input Validation
--ontology is validated against registered ontology names in ontology_registry.json (fixed allowlist)
--annotation JSON is parsed with json.loads() and validated as a dict with required class and properties keys
--class names are validated against known classes in the ontology summary; unknown classes produce clear errors
--provided property names are validated as comma-separated strings and matched against known properties
--relationships JSON is parsed and validated as a non-empty list of dicts, each requiring subject_class, property, and object_class keys
Size/length caps reject abusive input (exit code 2): raw JSON inputs and annotation files are capped at 1,000,000 bytes; at most 1000 annotations/relationships/provided properties per call; each class or property name is capped at 500 characters. Class and property names must be strings.
File Access
Scripts read pre-processed JSON files from the references/ directory: ontology_registry.json, cmso_summary.json, cmso_constraints.json (all read-only)
No scripts write to the filesystem; all output goes to stdout
No network access is required
Tool Restrictions
Read: Used to inspect script source, reference files, and ontology constraint data
Bash: Used to execute the three Python validation scripts (schema_checker.py, completeness_checker.py, relationship_checker.py) with explicit argument lists
Safety Measures
No eval(), exec(), or dynamic code generation
All subprocess calls use explicit argument lists (no shell=True)
JSON input parsing uses json.loads() only (no pickle, no YAML with unsafe loaders)
Validation logic operates on pre-loaded in-memory data structures; no dynamic file discovery or traversal
Limitations
Constraints file is manually curated, not derived from OWL axioms
Does not validate data types (e.g., whether a value is actually a float vs string)
Does not validate cardinality (e.g., exactly one space group per structure)
Subclass checking uses simple parent traversal, not full OWL reasoning
References
Validation Rules — what is validated and why
CMSO Constraints — required/recommended properties per class
Subclass-aware domain matching (fixes substring false positives/negatives), nearest-match suggestions on unknown class/property, input size/length caps, eval and doc corrections
2026-02-25
1.0
Initial release with CMSO validation support
1---2name: ontology-validator3description: Validate material sample annotations against ontology constraints — check that class names and property names exist in the ontology, verify domain and range consistency for object property relationships, assess annotation completeness (required, recommended, and optional properties), and flag unknown or misspelled terms. Use when verifying that CMSO or other ontology annotations are correct before publishing, checking whether all required properties are present for a class like Crystal Structure or Unit Cell, auditing relationship triples between instances, or catching annotation errors early in a FAIR data workflow, even if the user only says "is my annotation correct" or "what am I missing."4---56# Ontology Validator78## Goal910Validate that material sample annotations comply with ontology constraints: correct class names, valid properties, consistent domain/range relationships, and required fields present.1112## Requirements1314- Python 3.10+15- No external dependencies (Python standard library only)16- Requires ontology-explorer's `cmso_summary.json` and `ontology_registry.json`1718## Inputs to Gather1920| Input | Description | Example |21|-------|-------------|---------|22| Annotation | JSON dict or list of annotation dicts | `{"class":"UnitCell","properties":{"has Bravais lattice":"cF"}}` |23| Class name | Class to check completeness for | `Crystal Structure` |24| Provided properties | Comma-separated property names | `"has unit cell,has space group"` |25| Relationships | JSON array of subject-property-object triples | `[{"subject_class":"Material","property":"has structure","object_class":"Crystal Structure"}]` |2627## Decision Guidance2829```30What do you need to validate?31├── An annotation (classes and properties are correct)32│ └── schema_checker.py --ontology cmso --annotation '<json>'33├── Completeness of a class annotation34│ └── completeness_checker.py --ontology cmso --class <name> --provided <props>35└── Object property relationships36 └── relationship_checker.py --ontology cmso --relationships '<json>'37```3839## Script Outputs (JSON Fields)4041| Script | Key Outputs |42|--------|-------------|43| `scripts/schema_checker.py` | `results.valid`, `results.errors` (each unknown_class/unknown_property error carries a `suggestions` array of nearest matches), `results.warnings`, `results.class_valid`, `results.properties_valid` |44| `scripts/completeness_checker.py` | `results.completeness_score`, `results.required_missing`, `results.recommended_missing`, `results.optional_missing`, `results.unrecognized` |45| `scripts/relationship_checker.py` | `results.valid`, `results.results`, `results.errors` |4647## Workflow48491. After mapping a sample with ontology-mapper, pass the annotations to `schema_checker.py` to verify correctness.502. For a specific class, use `completeness_checker.py` to see what required/recommended properties are missing.513. When building relationships between instances, use `relationship_checker.py` to ensure domain/range consistency.5253## Conversational Workflow Example5455```56User: I annotated my sample as CrystalStructure with properties hasUnitCell and hasBasis.57 Is this correct and complete?5859Agent: Let me both validate the annotation and check its completeness.6061[Runs: schema_checker.py --ontology cmso --annotation62 '{"class":"Crystal Structure","properties":{"has unit cell":true,"has basis":true}}' --json]63[Runs: completeness_checker.py --ontology cmso --class "Crystal Structure"64 --provided "has unit cell,has basis" --json]6566From schema_checker.py (results.warnings):67- has unit cell: valid for Crystal Structure68- has basis: domain_mismatch warning — its domain is "Unit Cell", not69 Crystal Structure (so this property belongs on the Unit Cell instance)7071From completeness_checker.py (results, completeness_score = 0.5):72- **required_missing**: has space group7374So: add "has space group" to the Crystal Structure annotation, and move75"has basis" onto the Unit Cell annotation. (The domain insight comes from76schema_checker.py's warnings; completeness_checker.py only reports the77missing required "has space group".)78```7980## CLI Examples8182```bash83# Validate an annotation84python3 skills/ontology/ontology-validator/scripts/schema_checker.py \85 --ontology cmso \86 --annotation '{"class":"Unit Cell","properties":{"has Bravais lattice":"cF"}}' \87 --json8889# Check completeness90python3 skills/ontology/ontology-validator/scripts/completeness_checker.py \91 --ontology cmso \92 --class "Crystal Structure" \93 --provided "has unit cell,has space group" \94 --json9596# Validate relationships97python3 skills/ontology/ontology-validator/scripts/relationship_checker.py \98 --ontology cmso \99 --relationships '[{"subject_class":"Computational Sample","property":"has material","object_class":"Material"}]' \100 --json101```102103## Error Handling104105| Error | Cause | Resolution |106|-------|-------|------------|107| `Class 'X' not found ... (did you mean 'Y'?)` | Invalid/misspelled class name | Apply the nearest-match `suggestions` from the error, or use ontology-explorer to find the correct name |108| `Property 'X' not found ... (did you mean 'Y'?)` | Invalid/misspelled property name | Apply the nearest-match `suggestions` from the error, or use property_lookup.py to search |109| `Annotation must be a dict` | Wrong input format | Provide valid JSON dict |110| `Relationships must be a non-empty list` | Wrong input format | Provide JSON array of relationship dicts |111112## Interpretation Guidance113114- **Errors** indicate definite problems (unknown class/property, range mismatch)115- **Warnings** indicate potential issues (domain mismatch — may be intentional for subclasses)116- **Completeness score**: 0.0-1.0 ratio of provided vs. total tracked117 properties. It weights required, recommended, and optional properties118 **equally**, so a moderate score (e.g. 0.5-0.67) can coexist with missing119 required properties. ALWAYS check `required_missing` first: a non-empty120 `required_missing` means the annotation is invalid regardless of the score.121- **required_missing**: must fix for valid annotation122- **recommended_missing**: should fix for quality123- **unrecognized**: may indicate typos or properties from a different ontology124125## Verification checklist126127- [ ] Ran `schema_checker.py --json` and recorded `results.valid`; confirmed `results.errors` is an empty array (a `valid:true` with any `unknown_class`/`unknown_property` error cannot occur, but confirm the array length is 0 rather than trusting the boolean alone).128- [ ] For every `domain_mismatch` entry in `results.warnings`, recorded the property, its reported `domain`, and the class it was applied to, then made an explicit keep-or-move decision (warnings are not auto-fixed and may be intentional for a subclass).129- [ ] Ran `completeness_checker.py --json` and confirmed `results.required_missing` is empty BEFORE quoting `completeness_score` — a non-empty `required_missing` means the annotation is invalid no matter how high the score is.130- [ ] Recorded the exact `completeness_score` together with the `required_missing`, `recommended_missing`, and `optional_missing` lists (do not paraphrase the score as "complete" while any required item is missing).131- [ ] For each unknown class/property error, recorded the `suggestions[0]` value and confirmed the corrected name actually exists in the ontology (re-ran the checker, or checked via ontology-explorer) rather than assuming the top suggestion is right.132- [ ] Ran `relationship_checker.py --json` for every subject-property-object triple and confirmed each per-triple `results.results[i].valid` is true; recorded any `results.errors` strings naming the offending `domain` or `range`.133- [ ] Confirmed the `--ontology` used (e.g. `cmso`, `asmo`) matches the ontology the annotation was authored against — a class can be "unknown" simply because the wrong constraints/summary file was loaded.134135## Common pitfalls & rationalizations136137| Tempting shortcut | Why it's wrong / what to do |138|-------------------|------------------------------|139| "completeness_score is 0.67, so the annotation is basically complete." | The score weights required, recommended, and optional tiers **equally**, so a high score can still hide a missing required property. Check `required_missing` first; a non-empty list means invalid regardless of score. |140| "schema_checker returned only warnings, no errors, so I'll ignore them." | `domain_mismatch` warnings flag a property attached to a class that is not (a subclass of) its domain — often the property belongs on a different instance. Record each warning and decide explicitly; don't auto-dismiss. |141| "The class name didn't match but the validator gave a suggestion, so I'll just use it." | `suggestions` come from stdlib `difflib` fuzzy matching (cutoff 0.6) and can be wrong or empty. Verify the suggested name exists in the ontology before applying it. |142| "Two of the three relationships passed, so the triples are fine." | `results.valid` is the AND over all triples; you must inspect each `results.results[i]` and its `errors`. A single failing domain/range check invalidates the relationship set. |143| "It returned valid:true, so the annotation is semantically correct." | The checker only verifies class/property existence and domain/range against a **manually curated** constraints file. It does not check data types, cardinality, or value plausibility — `valid:true` is necessary, not sufficient. |144| "Property exists in the ontology, so it applies to my class." | Existence is checked against the full property set; domain applicability is a separate subclass-aware check. A real property can still trigger a `domain_mismatch` warning on the wrong class. |145| "I'll trust the bare class name; substrings are close enough." | Domain/subclass matching is exact-equality plus parent traversal, NOT substring containment. `Material` is not credited with `Crystalline Material` properties; use the precise ontology class name. |146147## Security148149### Input Validation150- `--ontology` is validated against registered ontology names in `ontology_registry.json` (fixed allowlist)151- `--annotation` JSON is parsed with `json.loads()` and validated as a dict with required `class` and `properties` keys152- `--class` names are validated against known classes in the ontology summary; unknown classes produce clear errors153- `--provided` property names are validated as comma-separated strings and matched against known properties154- `--relationships` JSON is parsed and validated as a non-empty list of dicts, each requiring `subject_class`, `property`, and `object_class` keys155- Size/length caps reject abusive input (exit code 2): raw JSON inputs and annotation files are capped at 1,000,000 bytes; at most 1000 annotations/relationships/provided properties per call; each class or property name is capped at 500 characters. Class and property names must be strings.156157### File Access158- Scripts read pre-processed JSON files from the `references/` directory: `ontology_registry.json`, `cmso_summary.json`, `cmso_constraints.json` (all read-only)159- No scripts write to the filesystem; all output goes to stdout160- No network access is required161162### Tool Restrictions163- **Read**: Used to inspect script source, reference files, and ontology constraint data164- **Bash**: Used to execute the three Python validation scripts (`schema_checker.py`, `completeness_checker.py`, `relationship_checker.py`) with explicit argument lists165166### Safety Measures167- No `eval()`, `exec()`, or dynamic code generation168- All subprocess calls use explicit argument lists (no `shell=True`)169- JSON input parsing uses `json.loads()` only (no pickle, no YAML with unsafe loaders)170- Validation logic operates on pre-loaded in-memory data structures; no dynamic file discovery or traversal171172## Limitations173174- Constraints file is manually curated, not derived from OWL axioms175- Does not validate data types (e.g., whether a value is actually a float vs string)176- Does not validate cardinality (e.g., exactly one space group per structure)177- Subclass checking uses simple parent traversal, not full OWL reasoning178179## References180181- [Validation Rules](references/validation_rules.md) — what is validated and why182- [CMSO Constraints](references/cmso_constraints.json) — required/recommended properties per class183- [CMSO Guide](../ontology-explorer/references/cmso_guide.md) — CMSO ontology overview184185## Version History186187| Date | Version | Changes |188|------|---------|---------|189| 2026-06-23 | 1.2.0 | Subclass-aware domain matching (fixes substring false positives/negatives), nearest-match suggestions on unknown class/property, input size/length caps, eval and doc corrections |190| 2026-02-25 | 1.0 | Initial release with CMSO validation support |
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Validate material sample annotations against ontology constraints — check that class names and property names exist in the ontology, verify domain and range consistency for object property relationships, assess annotation completeness (required, recommended, and optional properties), and flag unknown or misspelled terms. Use when verifying that CMSO or other ontology annotations are correct before publishing, checking whether all required properties are present for a class like Crystal Structure or Unit Cell, auditing relationship triples between instances, or catching annotation errors early in a FAIR data workflow, even if the user only says "is my annotation correct" or "what am I missing." It is listed under Productivity on SkillMD.
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