diff --git a/docs/roadmap/implementation.md b/docs/roadmap/implementation.md
index 1e8115d5..ec5c02e7 100644
--- a/docs/roadmap/implementation.md
+++ b/docs/roadmap/implementation.md
@@ -217,6 +217,8 @@ cache paths, and local backend presence. No live profile resolution.
 
 ## Stage 3 — Implement Pipeline Document Rules
 
+**Status:** Completed 2026-09-13.
+
 **Goal:** Validate and normalize the complete pipeline file shape before
 catalog resolution.
 
diff --git a/internal/core/config/load.go b/internal/core/config/load.go
index 1bd8d9e0..4189bc7b 100644
--- a/internal/core/config/load.go
+++ b/internal/core/config/load.go
@@ -20,17 +20,20 @@ func loadDocument(path string, options LoadOptions) (*configkit.Result[Document]
 }
 
 func loadDocumentSource(source configkit.Source, options LoadOptions) (*configkit.Result[Document], error) {
+	state := newDocumentLoadState()
 	return configkit.Load(source, configkit.Options[Document]{
-		Definition: documentDefinition(),
+		Definition: documentDefinition(state),
 		Profile:    options.Profile,
 		Overrides:  options.Overrides,
 	})
 }
 
-func documentDefinition() configkit.Definition[Document] {
+func documentDefinition(state *documentLoadState) configkit.Definition[Document] {
 	return configkit.Definition[Document]{
 		Defaults: documentDefaults,
-		Resolve:  resolveDocumentOperations,
+		Resolve: func(document *Document, resolution *configkit.Resolution) error {
+			return resolveDocumentOperations(document, resolution, state)
+		},
 		Validate: validateDocumentOperations,
 		Version: &configkit.VersionRule{
 			Path:  configkit.Keys("version"),
diff --git a/internal/core/config/operational_document.go b/internal/core/config/operational_document.go
index c11002ea..01067a6a 100644
--- a/internal/core/config/operational_document.go
+++ b/internal/core/config/operational_document.go
@@ -10,12 +10,13 @@ import (
 	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
 )
 
-func resolveDocumentOperations(document *Document, resolution *configkit.Resolution) error {
+func resolveDocumentOperations(document *Document, resolution *configkit.Resolution, state *documentLoadState) error {
 	if document == nil {
 		return nil
 	}
 	normalizeDocumentPromptKit(document.PromptKit, resolution)
 	normalizeDocumentState(document, resolution)
+	normalizeDocumentPipelines(document, resolution, state)
 	deriveDocumentExtractWorkers(document, resolution)
 	return nil
 }
@@ -94,6 +95,7 @@ func validateDocumentOperations(document *Document, validation *configkit.Valida
 	validateDocumentConcurrency(document.Concurrency, validation)
 	validateDocumentPromptKit(document.PromptKit, validation)
 	validateDocumentState(document, validation)
+	validateDocumentPipelines(document, validation)
 }
 
 func validateDocumentConcurrency(concurrency *ConcurrencyDocument, validation *configkit.Validation) {
diff --git a/internal/core/config/pipeline_document.go b/internal/core/config/pipeline_document.go
new file mode 100644
index 00000000..8c283ec4
--- /dev/null
+++ b/internal/core/config/pipeline_document.go
@@ -0,0 +1,504 @@
+package config
+
+import (
+	"sort"
+	"strings"
+
+	configkit "gitea.maximumdirect.net/eric/ConfigKit"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
+)
+
+// documentLoadState keeps the spelling supplied by the user while resolver
+// operations move map entries to their canonical keys. It is intentionally
+// load-local: source-location handling consumes it during a later resolver
+// pass and it never becomes runtime configuration state.
+type documentLoadState struct {
+	originalPaths map[string]configkit.Path
+}
+
+func newDocumentLoadState() *documentLoadState {
+	return &documentLoadState{originalPaths: make(map[string]configkit.Path)}
+}
+
+func (state *documentLoadState) rememberPath(normalized, original configkit.Path) {
+	if state != nil {
+		state.originalPaths[normalized.String()] = original
+	}
+}
+
+// originalPath follows recorded map-key moves back to the spelling present in
+// the source. Resolver code that needs a source coordinate must use this
+// rather than reconstructing a path from a normalized identifier.
+func (state *documentLoadState) originalPath(path configkit.Path) configkit.Path {
+	if state == nil || len(state.originalPaths) == 0 {
+		return path
+	}
+	value := path.String()
+	for {
+		changed := false
+		segments := strings.Split(strings.TrimPrefix(value, "/"), "/")
+		for length := 1; length <= len(segments); length++ {
+			prefix := "/" + strings.Join(segments[:length], "/")
+			original, ok := state.originalPaths[prefix]
+			if !ok {
+				continue
+			}
+			value = original.String() + strings.TrimPrefix(value, prefix)
+			changed = true
+			break
+		}
+		if !changed {
+			break
+		}
+	}
+	if original, err := configkit.ParsePath(value); err == nil {
+		return original
+	}
+	return path
+}
+
+func normalizeDocumentPipelines(document *Document, resolution *configkit.Resolution, state *documentLoadState) {
+	if document == nil {
+		return
+	}
+	validateDocumentPipelinePresence(document, resolution)
+
+	pipelinesPath := configkit.Keys("pipelines")
+	for _, id := range sortedPipelineDocumentKeys(document.Pipelines) {
+		profile := document.Pipelines[id]
+		normalizePipelineDocument(&profile, pipelinesPath.Key(id), resolution, state)
+		document.Pipelines[id] = profile
+	}
+	document.Pipelines = normalizeDocumentMap(document.Pipelines, pipelinesPath, "pipeline identifier", resolution, state)
+}
+
+func validateDocumentPipelinePresence(document *Document, resolution *configkit.Resolution) {
+	pipelinesPath := configkit.Keys("pipelines")
+	for _, id := range sortedPipelineDocumentKeys(document.Pipelines) {
+		profile := document.Pipelines[id]
+		path := pipelinesPath.Key(id)
+		validatePipelineDocumentPresence(profile, path, resolution)
+	}
+}
+
+func validatePipelineDocumentPresence(profile PipelineDocument, path configkit.Path, resolution *configkit.Resolution) {
+	rejectDocumentNull(resolution, path.Key("llm_profile"), profile.LLMProfile == nil)
+	rejectDocumentNull(resolution, path.Key("structured_output_repair_attempts"), profile.StructuredOutputRepairAttempts == nil)
+	rejectDocumentNull(resolution, path.Key("validation_policy"), profile.ValidationPolicy == nil)
+	validateDocumentPolicyPresence(profile.ValidationPolicy, path.Key("validation_policy"), resolution)
+
+	stepsPath := path.Key("steps")
+	if resolution.IsExplicit(stepsPath) && profile.Steps == nil {
+		resolution.Error(stepsPath, "must not be null")
+	}
+	if resolution.IsExplicit(stepsPath) && len(profile.Steps) == 0 {
+		resolution.Error(stepsPath, "must contain at least one ordered step")
+	}
+	if resolution.IsExplicit(stepsPath) && resolution.IsExplicit(path.Key("artifacts")) {
+		resolution.Error(stepsPath, "must not be declared with artifacts", path.Key("artifacts"))
+	}
+
+	validateBindingDocumentPresence(profile.Input, path.Key("input"), resolution)
+	validateOptionalBindingDocumentPresence(profile.Chunk, path.Key("chunk"), resolution)
+	validateOptionalBindingDocumentPresence(profile.Output, path.Key("output"), resolution)
+	validateReferenceDocumentMapPresence(profile.References, path.Key("references"), resolution)
+	for _, laneID := range sortedLaneDocumentKeys(profile.Artifacts) {
+		validateArtifactLaneDocumentPresence(profile.Artifacts[laneID], path.Key("artifacts").Key(laneID), resolution)
+	}
+	for index, step := range profile.Steps {
+		stepPath := stepsPath.Index(index)
+		validateReferenceDocumentMapPresence(step.References, stepPath.Key("references"), resolution)
+		for _, laneID := range sortedLaneDocumentKeys(step.Artifacts) {
+			validateArtifactLaneDocumentPresence(step.Artifacts[laneID], stepPath.Key("artifacts").Key(laneID), resolution)
+		}
+	}
+}
+
+func validateArtifactLaneDocumentPresence(lane ArtifactLaneDocument, path configkit.Path, resolution *configkit.Resolution) {
+	if resolution.IsExplicit(path.Key("references")) {
+		resolution.Error(path.Key("references"), "artifact-lane references are not supported; use binding references")
+	}
+	validateBindingDocumentPresence(lane.Extract, path.Key("extract"), resolution)
+	validateOptionalBindingDocumentPresence(lane.Merge, path.Key("merge"), resolution)
+	validateOptionalBindingDocumentPresence(lane.Normalize, path.Key("normalize"), resolution)
+}
+
+func validateOptionalBindingDocumentPresence(binding *BindingDocument, path configkit.Path, resolution *configkit.Resolution) {
+	if binding == nil {
+		if resolution.IsExplicit(path) {
+			resolution.Error(path, "must not be null when configured")
+		}
+		return
+	}
+	validateBindingDocumentPresence(*binding, path, resolution)
+}
+
+func validateBindingDocumentPresence(binding BindingDocument, path configkit.Path, resolution *configkit.Resolution) {
+	rejectDocumentNull(resolution, path.Key("llm_profile"), binding.LLMProfile == nil)
+	rejectDocumentNull(resolution, path.Key("structured_output_repair_attempts"), binding.StructuredOutputRepairAttempts == nil)
+	rejectDocumentNull(resolution, path.Key("validation_policy"), binding.ValidationPolicy == nil)
+	validateDocumentPolicyPresence(binding.ValidationPolicy, path.Key("validation_policy"), resolution)
+	if binding.Validators == nil && resolution.IsExplicit(path.Key("validators")) {
+		resolution.Error(path.Key("validators"), "must not be null")
+	}
+	validateReferenceDocumentMapPresence(binding.References, path.Key("references"), resolution)
+	for index, validator := range binding.Validators {
+		validatorPath := path.Key("validators").Index(index)
+		rejectDocumentNull(resolution, validatorPath.Key("llm_profile"), validator.LLMProfile == nil)
+		rejectDocumentNull(resolution, validatorPath.Key("structured_output_repair_attempts"), validator.StructuredOutputRepairAttempts == nil)
+	}
+}
+
+func validateReferenceDocumentMapPresence(references map[string]ReferenceDocument, path configkit.Path, resolution *configkit.Resolution) {
+	for _, name := range sortedReferenceDocumentKeys(references) {
+		source := references[name]
+		sourcePath := path.Key(name)
+		rejectDocumentNull(resolution, sourcePath.Key("path"), source.Path == nil)
+		rejectDocumentNull(resolution, sourcePath.Key("artifact"), source.Artifact == nil)
+	}
+}
+
+func rejectDocumentNull(resolution *configkit.Resolution, path configkit.Path, isNil bool) {
+	if isNil && resolution.IsExplicit(path) {
+		resolution.Error(path, "must not be null")
+	}
+}
+
+func validateDocumentPolicyPresence(policy *ValidationPolicyDocument, path configkit.Path, resolution *configkit.Resolution) {
+	if policy == nil {
+		return
+	}
+	rejectDocumentNull(resolution, path.Key("producer_structural_failure"), policy.ProducerStructuralFailure == nil)
+	rejectDocumentNull(resolution, path.Key("semantic_rejection"), policy.SemanticRejection == nil)
+	rejectDocumentNull(resolution, path.Key("validator_failure"), policy.ValidatorFailure == nil)
+}
+
+func normalizePipelineDocument(profile *PipelineDocument, path configkit.Path, resolution *configkit.Resolution, state *documentLoadState) {
+	normalizePipelineDocumentString(resolution, path.Key("llm_profile"), &profile.LLMProfile, "trimmed pipeline LLM profile")
+	normalizeDocumentBinding(&profile.Input, path.Key("input"), resolution, state)
+	if profile.Chunk != nil {
+		normalizeDocumentBinding(profile.Chunk, path.Key("chunk"), resolution, state)
+	}
+	if profile.Output != nil {
+		normalizeDocumentBinding(profile.Output, path.Key("output"), resolution, state)
+	}
+	profile.References = normalizeDocumentReferences(profile.References, path.Key("references"), resolution, state)
+	for _, laneID := range sortedLaneDocumentKeys(profile.Artifacts) {
+		lane := profile.Artifacts[laneID]
+		normalizeArtifactLaneDocument(&lane, path.Key("artifacts").Key(laneID), resolution, state)
+		profile.Artifacts[laneID] = lane
+	}
+	profile.Artifacts = normalizeDocumentMap(profile.Artifacts, path.Key("artifacts"), "artifact lane identifier", resolution, state)
+	for index := range profile.Steps {
+		step := &profile.Steps[index]
+		stepPath := path.Key("steps").Index(index)
+		normalizeDocumentValue(resolution, stepPath.Key("id"), &step.ID, strings.TrimSpace(step.ID), "trimmed step identifier")
+		step.References = normalizeDocumentReferences(step.References, stepPath.Key("references"), resolution, state)
+		for _, laneID := range sortedLaneDocumentKeys(step.Artifacts) {
+			lane := step.Artifacts[laneID]
+			normalizeArtifactLaneDocument(&lane, stepPath.Key("artifacts").Key(laneID), resolution, state)
+			step.Artifacts[laneID] = lane
+		}
+		step.Artifacts = normalizeDocumentMap(step.Artifacts, stepPath.Key("artifacts"), "artifact lane identifier", resolution, state)
+	}
+}
+
+func normalizeArtifactLaneDocument(lane *ArtifactLaneDocument, path configkit.Path, resolution *configkit.Resolution, state *documentLoadState) {
+	normalizeDocumentBinding(&lane.Extract, path.Key("extract"), resolution, state)
+	if lane.Merge != nil {
+		normalizeDocumentBinding(lane.Merge, path.Key("merge"), resolution, state)
+	}
+	if lane.Normalize != nil {
+		normalizeDocumentBinding(lane.Normalize, path.Key("normalize"), resolution, state)
+	}
+	for index := range lane.Validators {
+		normalizeValidatorDocument(&lane.Validators[index], path.Key("validators").Index(index), resolution)
+	}
+}
+
+func normalizeDocumentBinding(binding *BindingDocument, path configkit.Path, resolution *configkit.Resolution, state *documentLoadState) {
+	normalizeDocumentValue(resolution, path.Key("module"), &binding.Module, strings.TrimSpace(binding.Module), "trimmed module identifier")
+	normalizePipelineDocumentString(resolution, path.Key("llm_profile"), &binding.LLMProfile, "trimmed binding LLM profile")
+	binding.References = normalizeDocumentReferences(binding.References, path.Key("references"), resolution, state)
+	for index := range binding.Validators {
+		normalizeValidatorDocument(&binding.Validators[index], path.Key("validators").Index(index), resolution)
+	}
+}
+
+func normalizeValidatorDocument(validator *ValidatorDocument, path configkit.Path, resolution *configkit.Resolution) {
+	normalizeDocumentValue(resolution, path.Key("module"), &validator.Module, strings.TrimSpace(validator.Module), "trimmed validator module identifier")
+	normalizePipelineDocumentString(resolution, path.Key("llm_profile"), &validator.LLMProfile, "trimmed validator LLM profile")
+}
+
+func normalizeDocumentReferences(references map[string]ReferenceDocument, path configkit.Path, resolution *configkit.Resolution, state *documentLoadState) map[string]ReferenceDocument {
+	for _, name := range sortedReferenceDocumentKeys(references) {
+		source := references[name]
+		sourcePath := path.Key(name)
+		normalizePipelineDocumentString(resolution, sourcePath.Key("path"), &source.Path, "trimmed reference path")
+		if source.Artifact != nil {
+			normalizeDocumentValue(resolution, sourcePath.Key("artifact").Key("step"), &source.Artifact.Step, strings.TrimSpace(source.Artifact.Step), "trimmed artifact step selector")
+			normalizeDocumentValue(resolution, sourcePath.Key("artifact").Key("lane"), &source.Artifact.Lane, strings.TrimSpace(source.Artifact.Lane), "trimmed artifact lane selector")
+		}
+		references[name] = source
+	}
+	return normalizeDocumentMap(references, path, "reference name", resolution, state)
+}
+
+func normalizeDocumentValue[T comparable](resolution *configkit.Resolution, path configkit.Path, target *T, value T, reason string) {
+	if target == nil || !resolution.IsExplicit(path) {
+		return
+	}
+	if *target != value {
+		resolution.Record(path, configkit.ChangeNormalization, reason)
+		*target = value
+	}
+}
+
+func normalizePipelineDocumentString(resolution *configkit.Resolution, path configkit.Path, target **string, reason string) {
+	if target == nil || *target == nil || !resolution.IsExplicit(path) {
+		return
+	}
+	value := strings.TrimSpace(**target)
+	if **target != value {
+		resolution.Record(path, configkit.ChangeNormalization, reason)
+		**target = value
+	}
+}
+
+func normalizeDocumentMap[T any](values map[string]T, path configkit.Path, kind string, resolution *configkit.Resolution, state *documentLoadState) map[string]T {
+	if len(values) == 0 {
+		return values
+	}
+	keys := make([]string, 0, len(values))
+	for key := range values {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	canonical := make(map[string]string, len(values))
+	valid := true
+	for _, key := range keys {
+		trimmed := strings.TrimSpace(key)
+		if trimmed == "" {
+			resolution.Error(path.Key(key), kind+" must not be empty")
+			valid = false
+			continue
+		}
+		if first, exists := canonical[trimmed]; exists {
+			resolution.Error(path.Key(key), kind+" collides after whitespace normalization", path.Key(first))
+			valid = false
+			continue
+		}
+		canonical[trimmed] = key
+	}
+	if !valid {
+		return values
+	}
+	result := make(map[string]T, len(values))
+	changed := false
+	dependencies := make([]configkit.Path, 0, len(keys))
+	for _, key := range keys {
+		trimmed := strings.TrimSpace(key)
+		result[trimmed] = values[key]
+		dependencies = append(dependencies, path.Key(key))
+		if trimmed != key {
+			changed = true
+			state.rememberPath(path.Key(trimmed), path.Key(key))
+		}
+	}
+	if changed {
+		resolution.Record(path, configkit.ChangeNormalization, "normalized "+kind+" keys", dependencies...)
+		values = result
+	}
+	return values
+}
+
+func validateDocumentPipelines(document *Document, validation *configkit.Validation) {
+	if document == nil {
+		return
+	}
+	pipelinesPath := configkit.Keys("pipelines")
+	for _, id := range sortedPipelineDocumentKeys(document.Pipelines) {
+		profile := document.Pipelines[id]
+		path := pipelinesPath.Key(id)
+		validatePipelineDocument(profile, path, validation)
+	}
+}
+
+func validatePipelineDocument(profile PipelineDocument, path configkit.Path, validation *configkit.Validation) {
+	validateSelectedDocumentProfile(profile.LLMProfile, path.Key("llm_profile"), validation)
+	validateDocumentRepairAttempts(profile.StructuredOutputRepairAttempts, path.Key("structured_output_repair_attempts"), validation)
+	validateDocumentPolicy(profile.ValidationPolicy, path.Key("validation_policy"), validation)
+	validateDocumentBinding(profile.Input, path.Key("input"), "input", false, false, validation)
+	if profile.Chunk != nil {
+		validateDocumentBinding(*profile.Chunk, path.Key("chunk"), "chunk", true, true, validation)
+	}
+	if profile.Output != nil {
+		validateDocumentBinding(*profile.Output, path.Key("output"), "output", false, false, validation)
+	}
+	validateDocumentReferences(profile.References, path.Key("references"), false, validation)
+
+	seenLanes := make(map[string]configkit.Path)
+	if profile.Steps != nil {
+		seenSteps := make(map[string]configkit.Path)
+		for index, step := range profile.Steps {
+			stepPath := path.Key("steps").Index(index)
+			if strings.TrimSpace(step.ID) == "" {
+				validation.Error(stepPath.Key("id"), "must not be empty")
+			} else if first, exists := seenSteps[step.ID]; exists {
+				validation.Error(stepPath.Key("id"), "must be unique", first)
+			} else {
+				seenSteps[step.ID] = stepPath.Key("id")
+			}
+			validateDocumentReferences(step.References, stepPath.Key("references"), true, validation)
+			validateDocumentLanes(step.Artifacts, stepPath.Key("artifacts"), seenLanes, validation)
+		}
+		return
+	}
+	validateDocumentLanes(profile.Artifacts, path.Key("artifacts"), seenLanes, validation)
+}
+
+func validateDocumentLanes(lanes map[string]ArtifactLaneDocument, path configkit.Path, seen map[string]configkit.Path, validation *configkit.Validation) {
+	for _, id := range sortedLaneDocumentKeys(lanes) {
+		lanePath := path.Key(id)
+		if first, exists := seen[id]; exists {
+			validation.Error(lanePath, "artifact lane identifier must be unique across steps", first)
+		} else {
+			seen[id] = lanePath
+		}
+		lane := lanes[id]
+		validateDocumentBinding(lane.Extract, lanePath.Key("extract"), "extract", true, true, validation)
+		if lane.Merge != nil {
+			validateDocumentBinding(*lane.Merge, lanePath.Key("merge"), "merge", true, true, validation)
+		}
+		if lane.Normalize != nil {
+			validateDocumentBinding(*lane.Normalize, lanePath.Key("normalize"), "normalize", true, true, validation)
+		}
+		if len(lane.Validators) > 0 {
+			validation.Error(lanePath.Key("validators"), "artifact-lane validators are not supported; attach validators to a binding")
+		}
+	}
+}
+
+func validateDocumentBinding(binding BindingDocument, path configkit.Path, slot string, referencesAllowed, validatorsAllowed bool, validation *configkit.Validation) {
+	if strings.TrimSpace(binding.Module) == "" {
+		validation.Error(path.Key("module"), "must not be empty")
+	}
+	validateSelectedDocumentProfile(binding.LLMProfile, path.Key("llm_profile"), validation)
+	validateDocumentRepairAttempts(binding.StructuredOutputRepairAttempts, path.Key("structured_output_repair_attempts"), validation)
+	if binding.Retries < 0 {
+		validation.Error(path.Key("retries"), "must be greater than or equal to zero")
+	}
+	if binding.ValidationPolicy != nil {
+		if slot != "chunk" && slot != "extract" && slot != "merge" && slot != "normalize" {
+			validation.Error(path.Key("validation_policy"), "is not supported for this binding")
+		}
+		validateDocumentPolicy(binding.ValidationPolicy, path.Key("validation_policy"), validation)
+	}
+	if len(binding.References) > 0 && !referencesAllowed {
+		validation.Error(path.Key("references"), "are not supported for this binding")
+	}
+	if referencesAllowed {
+		validateDocumentReferences(binding.References, path.Key("references"), true, validation)
+	}
+	if len(binding.Validators) > 0 && !validatorsAllowed {
+		validation.Error(path.Key("validators"), "are not supported for this binding")
+	}
+	for index, validator := range binding.Validators {
+		validateValidatorDocument(validator, path.Key("validators").Index(index), validation)
+	}
+}
+
+func validateValidatorDocument(validator ValidatorDocument, path configkit.Path, validation *configkit.Validation) {
+	if strings.TrimSpace(validator.Module) == "" {
+		validation.Error(path.Key("module"), "must not be empty")
+	}
+	validateSelectedDocumentProfile(validator.LLMProfile, path.Key("llm_profile"), validation)
+	validateDocumentRepairAttempts(validator.StructuredOutputRepairAttempts, path.Key("structured_output_repair_attempts"), validation)
+	if validator.Retries < 0 {
+		validation.Error(path.Key("retries"), "must be greater than or equal to zero")
+	}
+}
+
+func validateDocumentReferences(references map[string]ReferenceDocument, path configkit.Path, generatedAllowed bool, validation *configkit.Validation) {
+	for _, name := range sortedReferenceDocumentKeys(references) {
+		source := references[name]
+		sourcePath := path.Key(name)
+		hasPath := source.Path != nil && strings.TrimSpace(*source.Path) != ""
+		hasArtifact := source.Artifact != nil
+		if hasPath == hasArtifact {
+			validation.Error(sourcePath, "must select exactly one reference source")
+			continue
+		}
+		if hasPath {
+			continue
+		}
+		if !generatedAllowed {
+			validation.Error(sourcePath.Key("artifact"), "is not supported here; use an external path")
+			continue
+		}
+		if strings.TrimSpace(source.Artifact.Step) == "" {
+			validation.Error(sourcePath.Key("artifact").Key("step"), "must not be empty")
+		}
+		if strings.TrimSpace(source.Artifact.Lane) == "" {
+			validation.Error(sourcePath.Key("artifact").Key("lane"), "must not be empty")
+		}
+	}
+}
+
+func validateSelectedDocumentProfile(value *string, path configkit.Path, validation *configkit.Validation) {
+	if value != nil && strings.TrimSpace(*value) == "" {
+		validation.Error(path, "must not be empty when set")
+	}
+}
+
+func validateDocumentRepairAttempts(value *int, path configkit.Path, validation *configkit.Validation) {
+	if value != nil && (*value < 0 || *value > 3) {
+		validation.Error(path, "must be between zero and three")
+	}
+}
+
+func validateDocumentPolicy(policy *ValidationPolicyDocument, path configkit.Path, validation *configkit.Validation) {
+	if policy == nil {
+		return
+	}
+	if policy.ProducerStructuralFailure != nil {
+		switch *policy.ProducerStructuralFailure {
+		case pipeline.ProducerStructuralFailureFailRun, pipeline.ProducerStructuralFailureRejectOutput:
+		default:
+			validation.Error(path.Key("producer_structural_failure"), "must be fail_run or reject_output")
+		}
+	}
+	if policy.SemanticRejection != nil {
+		switch *policy.SemanticRejection {
+		case pipeline.SemanticRejectionFailRun, pipeline.SemanticRejectionRejectOutput:
+		default:
+			validation.Error(path.Key("semantic_rejection"), "must be fail_run or reject_output")
+		}
+	}
+	if policy.ValidatorFailure != nil {
+		switch *policy.ValidatorFailure {
+		case pipeline.ValidatorFailureWarnContinue, pipeline.ValidatorFailureFailRun:
+		default:
+			validation.Error(path.Key("validator_failure"), "must be warn_continue or fail_run")
+		}
+	}
+}
+
+func sortedPipelineDocumentKeys(values map[string]PipelineDocument) []string {
+	return sortedDocumentKeys(values)
+}
+func sortedLaneDocumentKeys(values map[string]ArtifactLaneDocument) []string {
+	return sortedDocumentKeys(values)
+}
+func sortedReferenceDocumentKeys(values map[string]ReferenceDocument) []string {
+	return sortedDocumentKeys(values)
+}
+
+func sortedDocumentKeys[T any](values map[string]T) []string {
+	keys := make([]string, 0, len(values))
+	for key := range values {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	return keys
+}
diff --git a/internal/core/config/pipeline_document_test.go b/internal/core/config/pipeline_document_test.go
new file mode 100644
index 00000000..b69828fe
--- /dev/null
+++ b/internal/core/config/pipeline_document_test.go
@@ -0,0 +1,197 @@
+package config
+
+import (
+	"errors"
+	"testing"
+
+	configkit "gitea.maximumdirect.net/eric/ConfigKit"
+)
+
+func TestDocumentPipelineNormalizesCanonicalIdentifiers(t *testing.T) {
+	t.Parallel()
+
+	loaded, err := loadDocumentSource(configkit.Bytes("document.yml", []byte(`version: 5
+pipelines:
+  " session ":
+    llm_profile: " local "
+    input:
+      module: " seriatim "
+    artifacts:
+      " spells ":
+        extract:
+          module: " dnd/spells "
+          structured_output_repair_attempts: 0
+          validators: []
+        merge:
+          module: dnd/merge
+          references:
+            previous:
+              artifact:
+                step: " default "
+                lane: " spells "
+`)), LoadOptions{})
+	if err != nil {
+		var loadError *configkit.LoadError
+		if errors.As(err, &loadError) {
+			t.Fatalf("loadDocumentSource() diagnostics = %#v", loadError.Diagnostics())
+		}
+		t.Fatalf("loadDocumentSource() error = %v", err)
+	}
+	profile, ok := loaded.Config.Pipelines["session"]
+	if !ok || profile.Input.Module != "seriatim" || profile.LLMProfile == nil || *profile.LLMProfile != "local" {
+		t.Fatalf("normalized pipeline = %#v", loaded.Config.Pipelines)
+	}
+	lane, ok := profile.Artifacts["spells"]
+	if !ok || lane.Extract.StructuredOutputRepairAttempts == nil || *lane.Extract.StructuredOutputRepairAttempts != 0 || lane.Extract.Validators == nil || len(lane.Extract.Validators) != 0 {
+		t.Fatalf("normalized lane = %#v", profile.Artifacts)
+	}
+	selector := lane.Merge.References["previous"].Artifact
+	if selector == nil || selector.Step != "default" || selector.Lane != "spells" {
+		t.Fatalf("artifact selector = %#v", selector)
+	}
+}
+
+func TestDocumentPipelineRejectsInvalidShapes(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		source string
+		path   string
+	}{
+		{
+			name: "both pipeline forms",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim}
+    artifacts: {}
+    steps:
+      - id: first
+        artifacts: {}
+`,
+			path: "/pipelines/session/steps",
+		},
+		{
+			name: "empty ordered steps",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim}
+    steps: []
+`,
+			path: "/pipelines/session/steps",
+		},
+		{
+			name: "normalized pipeline collision",
+			source: `version: 5
+pipelines:
+  session: {input: {module: seriatim}}
+  " session ": {input: {module: seriatim}}
+`,
+			path: "/pipelines/session",
+		},
+		{
+			name: "duplicate lane across ordered steps",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim}
+    steps:
+      - id: first
+        artifacts: {summary: {extract: {module: dnd/summary}}}
+      - id: second
+        artifacts: {summary: {extract: {module: dnd/summary}}}
+`,
+			path: "/pipelines/session/steps/1/artifacts/summary",
+		},
+		{
+			name: "invalid reference union",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim}
+    references:
+      party: {path: ./party.txt, artifact: {step: one, lane: summary}}
+`,
+			path: "/pipelines/session/references/party",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			_, err := loadDocumentSource(configkit.Bytes("document.yml", []byte(test.source)), LoadOptions{})
+			assertDocumentDiagnosticAt(t, err, test.path)
+		})
+	}
+}
+
+func TestDocumentPipelineRejectsInvalidBindingPlacementAndPresence(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		source string
+		path   string
+	}{
+		{
+			name: "input validators",
+			source: `version: 5
+pipelines:
+  session:
+    input:
+      module: seriatim
+      validators: [{module: generic/valid_json}]
+`,
+			path: "/pipelines/session/input/validators",
+		},
+		{
+			name: "blank selected profile",
+			source: `version: 5
+pipelines:
+  session:
+    llm_profile: "   "
+    input: {module: seriatim}
+`,
+			path: "/pipelines/session/llm_profile",
+		},
+		{
+			name: "null validators",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim}
+    chunk: {module: generic/chunk, validators: null}
+`,
+			path: "/pipelines/session/chunk/validators",
+		},
+		{
+			name: "negative retry budget",
+			source: `version: 5
+pipelines:
+  session:
+    input: {module: seriatim, retries: -1}
+`,
+			path: "/pipelines/session/input/retries",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			_, err := loadDocumentSource(configkit.Bytes("document.yml", []byte(test.source)), LoadOptions{})
+			assertDocumentDiagnosticAt(t, err, test.path)
+		})
+	}
+}
+
+func assertDocumentDiagnosticAt(t *testing.T, err error, path string) {
+	t.Helper()
+	var loadError *configkit.LoadError
+	if !errors.As(err, &loadError) {
+		t.Fatalf("error = %v, want ConfigKit load error", err)
+	}
+	for _, diagnostic := range loadError.Diagnostics() {
+		if diagnostic.Path.String() == path {
+			return
+		}
+	}
+	t.Fatalf("diagnostics = %#v, want a diagnostic at %s", loadError.Diagnostics(), path)
+}