Use when asked to validate an IFC file, check whether an IFC model is conformant, run a pre-delivery quality gate on an IFC file, decide if an IFC file is valid, or triage a buildingSMART validation report. Prevents skipping the STEP-syntax gate, treating a warning as a file-invalidating error, reading a hidden pass as a skipped check, validating against the wrong schema, and confusing schema conformance with project information requirements. Covers the buildingSMART five-stage validation pipeline (STEP syntax, schema, normative, industry practice, bSDD), the Gherkin functional-part coverage map, the fifteen-item anti-pattern checklist, finding triage by severity, and routing each fault class to the matching ifc-errors skill, across IFC2x3, IFC4 and IFC4.3. Keywords: validate IFC file, is my IFC file valid, IFC validation pipeline, buildingSMART validation service, IFC conformance check, validation report triage, pre-delivery quality gate, schema validation, Gherkin normative rules, implementer agreement, inf
Use when asked to validate an IFC file, check whether an IFC model is conformant, run a pre-delivery quality gate on an IFC file, decide if an IFC file is valid, or triage a buildingSMART validation report. Prevents skipping the STEP-syntax gate, treating a warning as a file-invalidating error, reading a hidden pass as a skipped check, validating against the wrong schema, and confusing schema conformance with project information requirements. Covers the buildingSMART five-stage validation pipeline (STEP syntax, schema, normative, industry practice, bSDD), the Gherkin functional-part coverage map, the fifteen-item anti-pattern checklist, finding triage by severity, and routing each fault class to the matching ifc-errors skill, across IFC2x3, IFC4 and IFC4.3. Keywords: validate IFC file, is my IFC file valid, IFC validation pipeline, buildingSMART validation service, IFC conformance check, validation report triage, pre-delivery quality gate, schema validation, Gherkin normative rules, implementer agreement, informal proposition, industry practice warning, "is this IFC file ok", "how do I check an IFC file", "my IFC file failed validation", error vs warning, validation checklist, IFC quality gate, what makes an IFC file valid.
license
MIT
compatibility
Designed for Claude Code. Requires IFC IFC2x3, IFC4, IFC4.3.
metadata
{"author":"OpenAEC-Foundation","version":"1.0"}
IFC File Validator (Orchestration)
Drive a complete, ordered validation pass over an IFC file. This is an
ORCHESTRATION skill : it sequences the buildingSMART five-stage validation
pipeline, walks the fifteen-item anti-pattern catalog, triages every finding by
severity, and routes each fault class to the matching ifc-errors-* skill that
holds the detailed fix.
This skill answers one question : is this IFC file conformant, and if not,
where is the fault and which skill fixes it. It does NOT itself teach the fixes.
It is the conductor ; the ifc-errors-* skills are the instruments.
Scope boundary : this skill checks SCHEMA CONFORMANCE (the file obeys the IFC
standard). It does NOT check PROJECT INFORMATION REQUIREMENTS (the file carries
the data a specific project demanded). Information completeness beyond schema
conformance belongs to ifc-agents-quality-checker. Project requirements are
expressed in IDS, which is out of this package scope. For the conceptual
validation MODEL see ifc-core-validation.
Quick Reference
The five-stage validation pipeline
The buildingSMART validation service runs these stages in order. ALWAYS run
them in this order : a later stage assumes the earlier one passed.
Stage
Checks
Failure severity
Routes to
1. STEP Syntax
ISO 10303-21 file structure, header, string escaping
error : file rejected
ifc-errors-encoding-issues
2. Schema : version
schema id is IFC2X3, IFC4, or IFC4X3_ADD2
error
ifc-errors-version-mismatch
2. Schema : compliance
attribute types, cardinalities, inverse cardinalities, WHERE rules, global rules, abstract instantiation
error
ifc-errors-schema-validation
3. Normative : Implementer Agreements
ratified Gherkin normative rules
error
the fault-specific ifc-errors-* skill
3. Normative : Informal Propositions
mandatory rules not yet ratified
error
the fault-specific ifc-errors-* skill
4. Industry Practice
common-practice, sensible-default checks
warning only
ifc-agents-quality-checker
5. bSDD Compliance
classification and property alignment with bSDD
error or warning
ifc-errors-property-set-mistakes
Stage 5 (bSDD) is temporarily DISABLED in the public validation service as of
service version v0.6.6. ALWAYS report it as disabled, NEVER as pass.
Outcome severities
Five severities : pass, warning, error, not applicable, disabled.
error invalidates the file. The file is non-conformant.
warning does NOT invalidate the file. Industry-practice checks only warn.
pass, not applicable and disabled results are HIDDEN by default in the
report. ALWAYS read a check absent from the visible report as PASSED or not
run, NEVER as a missing or skipped requirement.
Orchestration rules
ALWAYS run stage 1 first. If STEP syntax fails, STOP : no later stage can run
on a file that does not parse.
ALWAYS confirm the declared schema version before stage 2 compliance : a
compliance check is meaningless against the wrong schema.
NEVER report a file as "valid" while any stage 1, 2, or 3 finding is an
error. NEVER report a file as "invalid" when the only findings are stage 4
warning results.
ALWAYS route each finding to the owning ifc-errors-* skill rather than
improvising a fix here.
Decision Trees
Tree A : "Validate this IFC file"
A validation pass is requested on an IFC file.
|
+-- Stage 1 : Does the file parse as ISO 10303-21 STEP?
| No : header malformed, string escaping broken, encoding wrong.
| -> ERROR. STOP the pipeline. Route to ifc-errors-encoding-issues.
| Report : file rejected before schema check.
| Yes : continue.
|
+-- Stage 2a : Is FILE_SCHEMA one of IFC2X3, IFC4, IFC4X3_ADD2?
| No, or it disagrees with the entities used.
| -> ERROR. Route to ifc-errors-version-mismatch. Continue with the
| version actually declared.
|
+-- Stage 2b : Schema compliance. Walk anti-patterns 3, 5, 6, 14, 15.
| Abstract instantiation, WHERE-rule break, cardinality, wrong type,
| deprecated entity, derived attribute set by hand.
| -> Each is an ERROR. Route per the anti-pattern map (Pattern 2).
|
+-- Stage 3 : Normative Gherkin rules. Walk anti-patterns 1, 4, 7, 11, 12.
| Missing spatial containment, geometry with no context, dangling
| reference, MVD-inconsistent geometry, degenerate geometry.
| -> Each is an ERROR. Route per the anti-pattern map.
|
+-- Stage 4 : Industry practice. Walk anti-patterns 8, 9.
| Missing material association, missing project property sets.
| -> WARNING only. The file stays valid. Route to
| ifc-agents-quality-checker for the completeness audit.
|
+-- Stage 5 : bSDD. Report as disabled (service v0.6.6+).
|
+-- Aggregate : any stage 1 to 3 error -> file is NON-CONFORMANT.
No error, warnings only -> file is CONFORMANT with warnings.
Tree B : "Triage a buildingSMART validation report"
A validation report is in hand and the question is what it means.
|
+-- Read the severity of each visible result.
|
+-- Any result with severity error?
| Yes -> The file is non-conformant. List every error, route each to its
| ifc-errors-* skill. The file is NOT deliverable.
| No -> continue.
|
+-- Only warning results visible?
| -> The file IS conformant. Warnings are industry-practice advice. Decide
| with the user whether to address them ; do not block delivery on them.
|
+-- A check the user expected is not in the report at all?
| -> It passed (pass is hidden by default), or it is not applicable, or it
| is disabled. NEVER read absence as "the checker skipped my file".
|
+-- The report says the file is valid but the user reports a real defect?
-> The defect is a PROJECT INFORMATION gap, not a schema fault. Route to
ifc-agents-quality-checker. Schema validity never proves completeness.
Patterns
Pattern 1 : Run the pipeline as a stop-on-syntax gate
ALWAYS treat the five stages as a gate, not a parallel scan.
Run stage 1 (STEP syntax). On any error, STOP and report. A file that does
not parse cannot be schema-checked : reporting later-stage results would be
fabricated.
Run stage 2 version check, then stage 2 compliance.
Run stage 3 normative checks (Implementer Agreements, then Informal
Propositions).
Run stage 4 industry-practice checks. These never stop the pipeline.
Report stage 5 (bSDD) as disabled.
Aggregate : the file is conformant if and only if no stage 1 to 3 finding
is an error.
The public validation service at https://validate.buildingsmart.org/ runs
exactly this pipeline. When a file cannot be uploaded to the service, ALWAYS
reproduce the same ORDER locally and state which stages were checked by which
tool.
Pattern 2 : The fifteen-item anti-pattern checklist
ALWAYS walk all fifteen. Each maps to a pipeline stage and an owning skill.
The full catalog with detection cues is in references/methods.md.
#
Anti-pattern
Stage
Owning skill
1
Missing spatial containment
3
ifc-errors-spatial-structure
2
Wrong unit assignment, model off by 1000x
2
ifc-errors-property-set-mistakes
3
Invalid or duplicated GlobalId
2
ifc-errors-schema-validation
4
Geometry without a representation context
3
ifc-errors-geometry-issues
5
Direct instantiation of an abstract entity
2
ifc-errors-schema-validation
6
Deprecated or removed entity for the schema
2
ifc-errors-version-mismatch
7
Broken reference or missing INVERSE link
2, 3
ifc-errors-broken-references
8
Broken or missing material association
4
ifc-errors-property-set-mistakes
9
Missing project-defined property sets
4
ifc-errors-property-set-mistakes
10
STEP encoding or header error
1
ifc-errors-encoding-issues
11
Geometry inconsistent with the declared MVD
3
ifc-errors-geometry-issues
12
Duplicated or degenerate geometry
3
ifc-errors-geometry-issues
13
Custom Pset using the reserved Pset_ prefix
2, 5
ifc-errors-property-set-mistakes
14
MaterialLayerSetUsage attached to a type object
2
ifc-errors-property-set-mistakes
15
Manually set derived TotalThickness
2
ifc-errors-property-set-mistakes
Items 1 to 12 are hard faults : 1, 4, 7, 11, 12 invalidate at stage 3 ; 3, 5,
6, 14, 15 invalidate at stage 2 ; 10 invalidates at stage 1. Items 8 and 9 are
stage-4 warnings : real defects, but they do NOT invalidate the file.
Pattern 3 : The Gherkin functional-part coverage map
Stage 3 normative rules are buildingSMART Gherkin rules, grouped under
three-letter functional-part prefixes. ALWAYS use the prefix to know which
domain a rule code touches and which skill owns it.
Prefix
Functional part
Owning skill
PJS
Project definition (context, directory of objects)
ifc-errors-schema-validation
GRF
Georeferencing
ifc-errors-geometry-issues
BLT
Built elements (walls, slabs, columns)
ifc-errors-schema-validation
GEM
Geometry representation
ifc-errors-geometry-issues
OJP
Object placement
ifc-errors-geometry-issues
SPS
Spatial breakdown
ifc-errors-spatial-structure
MAT
Materials
ifc-errors-property-set-mistakes
PSE
Properties for objects
ifc-errors-property-set-mistakes
QTY
Quantities for objects
ifc-errors-property-set-mistakes
CLS
Classification reference
ifc-errors-property-set-mistakes
POR
Port connectivity and nesting
ifc-errors-broken-references
A rule code is its prefix plus a number, for example GEM051, SPS001. The
prefix is the routing key. The full prefix list and detail are in
references/methods.md.
Pattern 4 : Triage findings by severity
ALWAYS classify every finding into exactly one of three buckets before
reporting.
ERROR : a stage 1, 2, or 3 error. The file is non-conformant. It is NOT
deliverable until fixed. Route to the owning skill.
WARNING : a stage 4 industry-practice warning. The file is conformant. The
warning is advice. Surface it, do not block on it.
INFORMATIONAL : a pass, not applicable, or disabled result, usually
hidden. It carries no action. NEVER escalate an informational result to a
warning or error.
NEVER collapse the three buckets. Treating a warning as an error blocks a valid
deliverable ; treating an error as a warning ships a broken file.
Pattern 5 : The validation report structure
A validation pass ALWAYS ends with a structured report, not a verdict word.
ALWAYS produce these sections :
Verdict : CONFORMANT or NON-CONFORMANT, derived strictly from Pattern 1
step 6.
Errors : one row per error : stage, anti-pattern number, owning skill,
one-line description.
Warnings : one row per industry-practice warning.
Not checked : stages and checks that were disabled or not applicable,
stated explicitly so the reader never assumes silent coverage.
Next actions : the ordered list of owning skills to invoke.
A worked report is in references/examples.md.
Version Notes
The validation pipeline, severities, and Gherkin rule layer apply to IFC2x3,
IFC4 and IFC4.3 files. The validation service accepts schema identifiers
IFC2X3, IFC4 and IFC4X3_ADD2.
Gherkin rules carry version tags (for example @version2) and an MVD
Background. ALWAYS check that a rule applies to the file's schema and MVD
before treating its result as binding.
Anti-pattern 6 (deprecated entities) is version-specific : IfcWallStandardCase
and the *StandardCase family are removed after IFC4 ; IfcBuildingElement
is renamed IfcBuiltElement in IFC4.3. Route version faults to
ifc-errors-version-mismatch, which holds the rename matrix.
Stage 5 (bSDD) is disabled in the public service as of v0.6.6. This is a
service state, not a schema-version property.
Reference Links
references/methods.md : the five-stage pipeline in full, the fifteen-item
anti-pattern catalog with detection cues, the complete Gherkin functional-part
prefix table, severity semantics, and how to run a single Gherkin rule.
references/examples.md : a worked validation run and a worked report.
references/anti-patterns.md : mistakes in the validation PROCESS itself.
