feat: add teaching asset prompts

.planning/REQUIREMENTS.md

@@ -59,11 +59,11 @@ interview-ready after each short practice loop.
 
 ### Teaching Assets
 
-- [ ] **ASSET-01**: System can generate prompt candidates for visual teaching
+- [x] **ASSET-01**: System can generate prompt candidates for visual teaching
   assets.
-- [ ] **ASSET-02**: Generated assets store source concept, evidence, prompt,
+- [x] **ASSET-02**: Generated assets store source concept, evidence, prompt,
   model config, and review state.
-- [ ] **ASSET-03**: Image model configuration verifies the actual OpenAI model
+- [x] **ASSET-03**: Image model configuration verifies the actual OpenAI model
   identifier before production calls.
 
 ## v2 Requirements
@@ -99,7 +99,7 @@ interview-ready after each short practice loop.
 | MEM-01..MEM-05 | Phase 3 | Complete |
 | PROG-01..PROG-05 | Phase 4 | Complete |
 | ONTO-01..ONTO-04 | Phase 5 | Complete |
-| ASSET-01..ASSET-03 | Phase 6 | Pending |
+| ASSET-01..ASSET-03 | Phase 6 | Complete |
 
 **Coverage:**
 - v1 requirements: 28 total
@@ -108,4 +108,4 @@ interview-ready after each short practice loop.
 
 ---
 *Requirements defined: 2026-04-26*
-*Last updated: 2026-04-26 after Phase 5 execution.*
+*Last updated: 2026-04-26 after Phase 6 execution.*

.planning/STATE.md

@@ -7,7 +7,7 @@ See: `.planning/PROJECT.md` (updated 2026-04-26)
 **Core value:** The user should feel and prove that they are becoming more
 interview-ready after each short practice loop.
 
-**Current focus:** Phase 6 planning: Teaching Assets.
+**Current focus:** v1 baseline complete; ready for milestone audit or frontend planning.
 
 ## Current Decisions
 
@@ -31,13 +31,15 @@ interview-ready after each short practice loop.
   challenge APIs derived from learner memory evidence.
 - Phase 5 ontology material ingestion is implemented and verified with
   source-backed candidate concepts, prerequisite edges, and candidate gaps.
+- Phase 6 teaching asset prompts are implemented and verified with source
+  evidence, model config, review state, and model-id verification guard.
 
 ## Next Actions
 
-1. Plan Phase 6 teaching asset prompt generation with GSD.
+1. Run a milestone audit across Phase 1 through Phase 6.
-2. Keep `docs/planning/WORKFLOW_CONTRACTS.md` aligned with Go structs during
+2. Choose the next milestone: frontend MVP, persistence, real workflow runtime,
-   future workflow implementation.
+   or document parser integration.
-3. Verify the production OpenAI image model identifier before real asset
+3. Verify the production OpenAI image model identifier before real image
    generation calls.
 
 ## Validation Log
@@ -61,6 +63,9 @@ interview-ready after each short practice loop.
 - 2026-04-26: Phase 5 implementation verified with `go test ./...`,
   `openspec validate bootstrap-job-tutor-platform --strict`, live material
   ingestion and ontology snapshot smoke, and Go source line-count check.
+- 2026-04-26: Phase 6 implementation verified with `go test ./...`,
+  `openspec validate bootstrap-job-tutor-platform --strict`, live
+  material-to-asset-prompt smoke, and Go source line-count check.
 
 ---
 *State initialized: 2026-04-26.*

.planning/phases/006-teaching-assets/006-CONTEXT.md

@@ -0,0 +1,39 @@
+# Phase 6 Context: Teaching Assets
+
+**Status:** Ready for execution
+**Started:** 2026-04-26
+
+## Goal
+
+Generate reviewable teaching asset prompt candidates from ontology concepts.
+
+## Inputs
+
+- OpenSpec generated study asset lineage requirement.
+- `docs/planning/WORKFLOW_CONTRACTS.md` TeachingAssetPrompt contract.
+- Phase 5 ontology candidates and source evidence.
+- PRD requirement to verify actual OpenAI model identifier before production
+  image calls.
+
+## Decisions
+
+- Generate prompt candidates only; do not call an image provider in this phase.
+- Default product model key remains `gpt-image-v2`.
+- Keep `requires_model_id_verification=true` until a future production
+  integration verifies the actual provider model identifier.
+- Persist prompt lineage with concept, evidence, model key, and review state.
+
+## Boundaries
+
+In scope:
+
+- Teaching asset prompt candidate service.
+- Asset prompt and snapshot APIs.
+- Model verification guard represented in output.
+
+Out of scope:
+
+- Real image generation calls.
+- Binary asset storage.
+- PPT export.
+- Provider-specific OpenAI SDK integration.

.planning/phases/006-teaching-assets/006-PLAN.md

@@ -0,0 +1,44 @@
+# Phase 6 Plan: Teaching Assets
+
+**Status:** Ready for execution
+**Phase Goal:** Create source-backed teaching asset prompt candidates.
+
+## Requirements Covered
+
+- ASSET-01: System can generate prompt candidates for visual teaching assets.
+- ASSET-02: Generated assets store source concept, evidence, prompt, model
+  config, and review state.
+- ASSET-03: Image model configuration verifies the actual OpenAI model
+  identifier before production calls.
+
+## Tasks
+
+### 1. Add teaching asset package
+
+- Define asset prompt candidate, asset type, review state, and snapshot types.
+- Add in-memory store and service.
+
+### 2. Generate prompts from ontology evidence
+
+- Select source-backed ontology concept by concept id.
+- Generate prompt candidate for diagram, lesson slice, worksheet, or interview
+  card.
+- Reject prompt generation when concept evidence is missing.
+
+### 3. Add HTTP endpoints
+
+- `POST /api/v1/teaching-assets/prompts`
+- `GET /api/v1/teaching-assets`
+
+### 4. Add tests and verification
+
+- Test prompt candidates keep concept and source evidence.
+- Test model verification guard remains true.
+- Test HTTP material-ingest-to-asset-prompt flow.
+- Run Go tests, OpenSpec validation, line-count check, and smoke.
+
+## Out of Scope
+
+- Real image generation.
+- Slide deck creation.
+- Asset publishing.

.planning/phases/006-teaching-assets/006-RESEARCH.md

@@ -0,0 +1,21 @@
+# Phase 6 Research: Teaching Assets
+
+## Findings
+
+The product needs lineage before generation. A prompt candidate that carries
+concept, source evidence, model key, and review state is already useful because
+it can be reviewed before spending image-generation cost or publishing content.
+
+## Recommended Shape
+
+- `internal/teachingassets` owns asset prompt candidates.
+- Use ontology snapshot as the source for concept/evidence lookup.
+- Generate prompts deterministically for MVP asset types.
+- Store `requires_model_id_verification=true` so production image generation is
+  blocked until the provider model identifier is verified.
+
+## Risks
+
+- Calling image generation before model ID verification would violate PRD.
+- Prompt candidates without evidence would weaken provenance.
+- Real slide/PPT generation should be a later phase.

.planning/phases/006-teaching-assets/006-SUMMARY.md

@@ -0,0 +1,38 @@
+# Phase 6 Summary
+
+**Status:** Complete
+**Completed:** 2026-04-26
+
+## Delivered
+
+- Added `internal/teachingassets` for prompt candidates and snapshots.
+- Added image model config key `TUTOR_IMAGE_MODEL_KEY`, defaulting to
+  `gpt-image-v2`.
+- Added workflow contract structs for `OntologyGap` and
+  `TeachingAssetPrompt`.
+- Added prompt generation from source-backed ontology concepts.
+- Added model-id verification guard on every prompt candidate.
+- Added HTTP endpoints:
+  - `POST /api/v1/teaching-assets/prompts`
+  - `GET /api/v1/teaching-assets`
+- Added service and HTTP tests.
+
+## Verification
+
+```powershell
+gofmt -w cmd internal
+go test ./...
+openspec validate bootstrap-job-tutor-platform --strict
+```
+
+Additional smoke check:
+
+- Material ingestion followed by teaching asset prompt generation returned a
+  source-backed prompt with `requires_model_id_verification=true`.
+
+## Deferred
+
+- Real image generation calls.
+- Provider SDK integration.
+- Binary asset storage.
+- Slide/PPT export.

.planning/phases/006-teaching-assets/006-VERIFICATION.md

@@ -0,0 +1,29 @@
+# Phase 6 Verification
+
+## Verdict
+
+PASS
+
+## Requirement Coverage
+
+- ASSET-01: PASS. Teaching asset prompt candidates can be generated for
+  ontology concepts.
+- ASSET-02: PASS. Prompt candidates store source concept, evidence, prompt,
+  model key, and review state.
+- ASSET-03: PASS. Prompt candidates carry
+  `requires_model_id_verification=true`, so production image generation remains
+  blocked until the provider model identifier is verified.
+
+## Evidence
+
+- `go test ./...` passed.
+- `openspec validate bootstrap-job-tutor-platform --strict` passed.
+- Live material-to-asset-prompt smoke passed.
+- Go source line-count check passed.
+
+## Residual Risk
+
+`gpt-image-v2` is currently treated as the product configuration key, not a
+confirmed provider model id. A future production generation phase must verify
+the actual OpenAI model identifier against current official docs before making
+real calls.

internal/app/server.go

@@ -9,6 +9,7 @@ import (
 	"tutor/internal/learnermemory"
 	"tutor/internal/ontology"
 	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
 	"tutor/internal/workflows"
 )
 
@@ -18,8 +19,9 @@ func NewServer(cfg config.Config) *http.Server {
 	memory := learnermemory.NewService(learnermemory.NewMemoryStore())
 	progress := progression.NewService(memory)
 	onto := ontology.NewService(ontology.NewMemoryStore())
+	assets := teachingassets.NewService(teachingassets.NewMemoryStore(), onto, cfg.ImageModelKey)
 	service := interview.NewService(store, runner, memory)
-	handler := httpapi.NewHandler(cfg, service, memory, progress, onto)
+	handler := httpapi.NewHandler(cfg, service, memory, progress, onto, assets)
 
 	return &http.Server{
 		Addr:    cfg.HTTPAddr,

internal/config/config.go

@@ -6,6 +6,7 @@ const (
 	defaultHTTPAddr        = ":8080"
 	defaultEnvironment     = "development"
 	defaultModelKey        = "deepseek-v4-flash"
+	defaultImageModelKey   = "gpt-image-v2"
 	defaultThirdOneBin     = "thirdone"
 	defaultWorkflowRuntime = ""
 )
@@ -15,6 +16,7 @@ type Config struct {
 	Environment     string
 	WorkflowRuntime string
 	ModelKey        string
+	ImageModelKey   string
 	ThirdOneBin     string
 }
 
@@ -24,6 +26,7 @@ func LoadFromEnv() Config {
 		Environment:     envOrDefault("TUTOR_ENV", defaultEnvironment),
 		WorkflowRuntime: envOrDefault("TUTOR_WORKFLOW_RUNTIME", defaultWorkflowRuntime),
 		ModelKey:        envOrDefault("TUTOR_MODEL_KEY", defaultModelKey),
+		ImageModelKey:   envOrDefault("TUTOR_IMAGE_MODEL_KEY", defaultImageModelKey),
 		ThirdOneBin:     envOrDefault("THIRDONE_BIN", defaultThirdOneBin),
 	}
 }

internal/config/config_test.go

@@ -7,6 +7,7 @@ func TestLoadFromEnvDefaults(t *testing.T) {
 	t.Setenv("TUTOR_ENV", "")
 	t.Setenv("TUTOR_WORKFLOW_RUNTIME", "")
 	t.Setenv("TUTOR_MODEL_KEY", "")
+	t.Setenv("TUTOR_IMAGE_MODEL_KEY", "")
 	t.Setenv("THIRDONE_BIN", "")
 
 	cfg := LoadFromEnv()
@@ -20,6 +21,9 @@ func TestLoadFromEnvDefaults(t *testing.T) {
 	if cfg.ModelKey != defaultModelKey {
 		t.Fatalf("ModelKey = %q, want %q", cfg.ModelKey, defaultModelKey)
 	}
+	if cfg.ImageModelKey != defaultImageModelKey {
+		t.Fatalf("ImageModelKey = %q, want %q", cfg.ImageModelKey, defaultImageModelKey)
+	}
 	if cfg.ThirdOneBin != defaultThirdOneBin {
 		t.Fatalf("ThirdOneBin = %q, want %q", cfg.ThirdOneBin, defaultThirdOneBin)
 	}
@@ -30,6 +34,7 @@ func TestLoadFromEnvOverrides(t *testing.T) {
 	t.Setenv("TUTOR_ENV", "test")
 	t.Setenv("TUTOR_WORKFLOW_RUNTIME", "runtime.yaml")
 	t.Setenv("TUTOR_MODEL_KEY", "other-model")
+	t.Setenv("TUTOR_IMAGE_MODEL_KEY", "other-image-model")
 	t.Setenv("THIRDONE_BIN", "C:/bin/thirdone.exe")
 
 	cfg := LoadFromEnv()
@@ -46,6 +51,9 @@ func TestLoadFromEnvOverrides(t *testing.T) {
 	if cfg.ModelKey != "other-model" {
 		t.Fatalf("ModelKey = %q", cfg.ModelKey)
 	}
+	if cfg.ImageModelKey != "other-image-model" {
+		t.Fatalf("ImageModelKey = %q", cfg.ImageModelKey)
+	}
 	if cfg.ThirdOneBin != "C:/bin/thirdone.exe" {
 		t.Fatalf("ThirdOneBin = %q", cfg.ThirdOneBin)
 	}

internal/httpapi/diagnostic_test.go

@@ -12,6 +12,7 @@ import (
 	"tutor/internal/learnermemory"
 	"tutor/internal/ontology"
 	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
 	"tutor/internal/workflows"
 )
 
@@ -20,7 +21,8 @@ func TestDiagnosticHTTPFlow(t *testing.T) {
 	service := interview.NewService(interview.NewMemoryStore(), workflows.NewStubRunner(), memory)
 	progress := progression.NewService(memory)
 	onto := ontology.NewService(ontology.NewMemoryStore())
-	handler := NewHandler(config.Config{Environment: "test", ModelKey: "deepseek-v4-flash"}, service, memory, progress, onto)
+	assets := teachingassets.NewService(teachingassets.NewMemoryStore(), onto, "gpt-image-v2")
+	handler := NewHandler(config.Config{Environment: "test", ModelKey: "deepseek-v4-flash"}, service, memory, progress, onto, assets)
 	routes := handler.Routes()
 
 	createBody := bytes.NewBufferString(`{

internal/httpapi/handler.go

@@ -9,6 +9,7 @@ import (
 	"tutor/internal/learnermemory"
 	"tutor/internal/ontology"
 	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
 )
 
 type Handler struct {
@@ -17,6 +18,7 @@ type Handler struct {
 	memory     *learnermemory.Service
 	progress   *progression.Service
 	ontology   *ontology.Service
+	assets     *teachingassets.Service
 }
 
 func NewHandler(
@@ -25,6 +27,7 @@ func NewHandler(
 	memory *learnermemory.Service,
 	progress *progression.Service,
 	ontology *ontology.Service,
+	assets *teachingassets.Service,
 ) Handler {
 	return Handler{
 		cfg:        cfg,
@@ -32,6 +35,7 @@ func NewHandler(
 		memory:     memory,
 		progress:   progress,
 		ontology:   ontology,
+		assets:     assets,
 	}
 }
 
@@ -46,6 +50,8 @@ func (h Handler) Routes() http.Handler {
 	mux.HandleFunc("GET /api/v1/learners/{userID}/next-challenge", h.getNextChallenge)
 	mux.HandleFunc("POST /api/v1/materials", h.ingestMaterial)
 	mux.HandleFunc("GET /api/v1/ontology", h.getOntology)
+	mux.HandleFunc("POST /api/v1/teaching-assets/prompts", h.generateTeachingAssetPrompt)
+	mux.HandleFunc("GET /api/v1/teaching-assets", h.getTeachingAssets)
 	return mux
 }
 

internal/httpapi/handler_test.go

@@ -11,6 +11,7 @@ import (
 	"tutor/internal/learnermemory"
 	"tutor/internal/ontology"
 	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
 	"tutor/internal/workflows"
 )
 
@@ -23,7 +24,8 @@ func TestHealth(t *testing.T) {
 	service := interview.NewService(interview.NewMemoryStore(), workflows.NewStubRunner(), memory)
 	progress := progression.NewService(memory)
 	onto := ontology.NewService(ontology.NewMemoryStore())
-	handler := NewHandler(cfg, service, memory, progress, onto)
+	assets := teachingassets.NewService(teachingassets.NewMemoryStore(), onto, cfg.ImageModelKey)
+	handler := NewHandler(cfg, service, memory, progress, onto, assets)
 
 	req := httptest.NewRequest(http.MethodGet, "/healthz", nil)
 	rec := httptest.NewRecorder()

internal/httpapi/ontology_test.go

@@ -12,6 +12,7 @@ import (
 	"tutor/internal/learnermemory"
 	"tutor/internal/ontology"
 	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
 	"tutor/internal/workflows"
 )
 
@@ -20,7 +21,8 @@ func TestOntologyHTTPFlow(t *testing.T) {
 	service := interview.NewService(interview.NewMemoryStore(), workflows.NewStubRunner(), memory)
 	progress := progression.NewService(memory)
 	onto := ontology.NewService(ontology.NewMemoryStore())
-	handler := NewHandler(config.Config{Environment: "test"}, service, memory, progress, onto)
+	assets := teachingassets.NewService(teachingassets.NewMemoryStore(), onto, "gpt-image-v2")
+	handler := NewHandler(config.Config{Environment: "test"}, service, memory, progress, onto, assets)
 	routes := handler.Routes()
 
 	body := bytes.NewBufferString(`{

internal/httpapi/teaching_assets.go

@@ -0,0 +1,47 @@
+package httpapi
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"tutor/internal/teachingassets"
+	"tutor/internal/workflows"
+)
+
+type generateTeachingAssetPromptRequest struct {
+	ConceptID string              `json:"concept_id"`
+	AssetType workflows.AssetType `json:"asset_type"`
+}
+
+func (h Handler) generateTeachingAssetPrompt(w http.ResponseWriter, r *http.Request) {
+	if h.assets == nil {
+		writeError(w, http.StatusNotFound, "teaching assets not configured")
+		return
+	}
+
+	var req generateTeachingAssetPromptRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeError(w, http.StatusBadRequest, "invalid JSON body")
+		return
+	}
+
+	prompt, err := h.assets.GeneratePrompt(teachingassets.GenerateInput{
+		ConceptID: req.ConceptID,
+		AssetType: req.AssetType,
+	})
+	if err != nil {
+		writeError(w, http.StatusBadRequest, err.Error())
+		return
+	}
+
+	writeJSON(w, http.StatusCreated, prompt)
+}
+
+func (h Handler) getTeachingAssets(w http.ResponseWriter, _ *http.Request) {
+	if h.assets == nil {
+		writeError(w, http.StatusNotFound, "teaching assets not configured")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, h.assets.Snapshot())
+}

internal/httpapi/teaching_assets_test.go

@@ -0,0 +1,64 @@
+package httpapi
+
+import (
+	"bytes"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"tutor/internal/config"
+	"tutor/internal/interview"
+	"tutor/internal/learnermemory"
+	"tutor/internal/ontology"
+	"tutor/internal/progression"
+	"tutor/internal/teachingassets"
+	"tutor/internal/workflows"
+)
+
+func TestTeachingAssetsHTTPFlow(t *testing.T) {
+	memory := learnermemory.NewService(learnermemory.NewMemoryStore())
+	service := interview.NewService(interview.NewMemoryStore(), workflows.NewStubRunner(), memory)
+	progress := progression.NewService(memory)
+	onto := ontology.NewService(ontology.NewMemoryStore())
+	assets := teachingassets.NewService(teachingassets.NewMemoryStore(), onto, "gpt-image-v2")
+	handler := NewHandler(config.Config{Environment: "test"}, service, memory, progress, onto, assets)
+	routes := handler.Routes()
+
+	ingestBody := bytes.NewBufferString(`{
+		"title":"Backend notes",
+		"body":"Idempotent API retries need transactions."
+	}`)
+	ingestReq := httptest.NewRequest(http.MethodPost, "/api/v1/materials", ingestBody)
+	ingestRec := httptest.NewRecorder()
+	routes.ServeHTTP(ingestRec, ingestReq)
+	if ingestRec.Code != http.StatusCreated {
+		t.Fatalf("ingest status = %d, body = %s", ingestRec.Code, ingestRec.Body.String())
+	}
+
+	promptBody := bytes.NewBufferString(`{
+		"concept_id":"http-idempotency",
+		"asset_type":"diagram"
+	}`)
+	promptReq := httptest.NewRequest(http.MethodPost, "/api/v1/teaching-assets/prompts", promptBody)
+	promptRec := httptest.NewRecorder()
+	routes.ServeHTTP(promptRec, promptReq)
+	if promptRec.Code != http.StatusCreated {
+		t.Fatalf("prompt status = %d, body = %s", promptRec.Code, promptRec.Body.String())
+	}
+
+	var prompt teachingassets.PromptCandidate
+	if err := json.NewDecoder(promptRec.Body).Decode(&prompt); err != nil {
+		t.Fatalf("decode prompt response: %v", err)
+	}
+	if !prompt.RequiresModelIDVerification {
+		t.Fatal("expected verification guard")
+	}
+
+	getReq := httptest.NewRequest(http.MethodGet, "/api/v1/teaching-assets", nil)
+	getRec := httptest.NewRecorder()
+	routes.ServeHTTP(getRec, getReq)
+	if getRec.Code != http.StatusOK {
+		t.Fatalf("assets status = %d, body = %s", getRec.Code, getRec.Body.String())
+	}
+}

internal/teachingassets/service.go

@@ -0,0 +1,96 @@
+package teachingassets
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"sync/atomic"
+	"time"
+
+	"tutor/internal/ontology"
+	"tutor/internal/workflows"
+)
+
+type Service struct {
+	store         Store
+	ontology      *ontology.Service
+	imageModelKey string
+	ids           atomic.Uint64
+}
+
+func NewService(store Store, ontology *ontology.Service, imageModelKey string) *Service {
+	return &Service{
+		store:         store,
+		ontology:      ontology,
+		imageModelKey: imageModelKey,
+	}
+}
+
+func (s *Service) GeneratePrompt(input GenerateInput) (PromptCandidate, error) {
+	if strings.TrimSpace(input.ConceptID) == "" {
+		return PromptCandidate{}, errors.New("concept_id is required")
+	}
+	assetType := input.AssetType
+	if assetType == "" {
+		assetType = workflows.AssetDiagram
+	}
+
+	concept, err := s.findConcept(input.ConceptID)
+	if err != nil {
+		return PromptCandidate{}, err
+	}
+	if len(concept.Evidence) == 0 {
+		return PromptCandidate{}, errors.New("concept has no source evidence")
+	}
+
+	prompt := PromptCandidate{
+		ID:                          s.nextID("asset-prompt"),
+		Concept:                     concept.Concept,
+		AssetType:                   assetType,
+		Prompt:                      buildPrompt(concept.Concept, assetType),
+		SourceEvidence:              append([]workflows.EvidenceRef(nil), concept.Evidence...),
+		ModelKey:                    s.imageModelKey,
+		RequiresModelIDVerification: true,
+		ReviewState:                 ReviewCandidate,
+		CreatedAt:                   time.Now().UTC(),
+	}
+	return s.store.SavePrompt(prompt)
+}
+
+func (s *Service) Snapshot() Snapshot {
+	return s.store.Snapshot()
+}
+
+func (s *Service) findConcept(id string) (ontology.ConceptCandidate, error) {
+	if s.ontology == nil {
+		return ontology.ConceptCandidate{}, errors.New("ontology not configured")
+	}
+	snapshot := s.ontology.Snapshot()
+	for _, concept := range snapshot.Concepts {
+		if concept.Concept.ID == id {
+			return concept, nil
+		}
+	}
+	return ontology.ConceptCandidate{}, errors.New("concept not found")
+}
+
+func buildPrompt(concept workflows.ConceptRef, assetType workflows.AssetType) string {
+	switch assetType {
+	case workflows.AssetLessonSlice:
+		return "Create a concise slide-like lesson slice explaining " + concept.Label +
+			" for a backend developer interview, with one example and one pitfall."
+	case workflows.AssetWorksheet:
+		return "Create a worksheet for practicing " + concept.Label +
+			" with short prompts, answer space, and a rubric."
+	case workflows.AssetInterviewCard:
+		return "Create an interview explanation card for " + concept.Label +
+			" with definition, production tradeoff, and follow-up question."
+	default:
+		return "Create a clear technical diagram explaining " + concept.Label +
+			" for a backend developer interview, grounded in the provided source evidence."
+	}
+}
+
+func (s *Service) nextID(prefix string) string {
+	return fmt.Sprintf("%s-%d", prefix, s.ids.Add(1))
+}

internal/teachingassets/service_test.go

@@ -0,0 +1,39 @@
+package teachingassets
+
+import (
+	"testing"
+
+	"tutor/internal/ontology"
+	"tutor/internal/workflows"
+)
+
+func TestGeneratePromptKeepsLineageAndVerificationGuard(t *testing.T) {
+	onto := ontology.NewService(ontology.NewMemoryStore())
+	if _, err := onto.Ingest(ontology.IngestInput{
+		Title: "Backend notes",
+		Body:  "Idempotent API retries need transactions.",
+	}); err != nil {
+		t.Fatalf("Ingest error: %v", err)
+	}
+	service := NewService(NewMemoryStore(), onto, "gpt-image-v2")
+
+	prompt, err := service.GeneratePrompt(GenerateInput{
+		ConceptID: "http-idempotency",
+		AssetType: workflows.AssetDiagram,
+	})
+	if err != nil {
+		t.Fatalf("GeneratePrompt error: %v", err)
+	}
+	if prompt.ModelKey != "gpt-image-v2" {
+		t.Fatalf("ModelKey = %q", prompt.ModelKey)
+	}
+	if !prompt.RequiresModelIDVerification {
+		t.Fatal("expected model id verification guard")
+	}
+	if prompt.ReviewState != ReviewCandidate {
+		t.Fatalf("ReviewState = %q", prompt.ReviewState)
+	}
+	if len(prompt.SourceEvidence) == 0 {
+		t.Fatal("expected source evidence")
+	}
+}

internal/teachingassets/store.go

@@ -0,0 +1,49 @@
+package teachingassets
+
+import (
+	"sync"
+
+	"tutor/internal/workflows"
+)
+
+type Store interface {
+	SavePrompt(PromptCandidate) (PromptCandidate, error)
+	Snapshot() Snapshot
+}
+
+type MemoryStore struct {
+	mu      sync.RWMutex
+	prompts []PromptCandidate
+}
+
+func NewMemoryStore() *MemoryStore {
+	return &MemoryStore{}
+}
+
+func (s *MemoryStore) SavePrompt(prompt PromptCandidate) (PromptCandidate, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.prompts = append(s.prompts, clonePrompt(prompt))
+	return prompt, nil
+}
+
+func (s *MemoryStore) Snapshot() Snapshot {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	return Snapshot{Prompts: clonePrompts(s.prompts)}
+}
+
+func clonePrompts(items []PromptCandidate) []PromptCandidate {
+	cloned := make([]PromptCandidate, len(items))
+	for i, item := range items {
+		cloned[i] = clonePrompt(item)
+	}
+	return cloned
+}
+
+func clonePrompt(prompt PromptCandidate) PromptCandidate {
+	prompt.SourceEvidence = append([]workflows.EvidenceRef(nil), prompt.SourceEvidence...)
+	return prompt
+}

internal/teachingassets/types.go

@@ -0,0 +1,34 @@
+package teachingassets
+
+import (
+	"time"
+
+	"tutor/internal/workflows"
+)
+
+type ReviewState string
+
+const (
+	ReviewCandidate ReviewState = "candidate"
+)
+
+type PromptCandidate struct {
+	ID                          string                  `json:"id"`
+	Concept                     workflows.ConceptRef    `json:"concept"`
+	AssetType                   workflows.AssetType     `json:"asset_type"`
+	Prompt                      string                  `json:"prompt"`
+	SourceEvidence              []workflows.EvidenceRef `json:"source_evidence"`
+	ModelKey                    string                  `json:"model_key"`
+	RequiresModelIDVerification bool                    `json:"requires_model_id_verification"`
+	ReviewState                 ReviewState             `json:"review_state"`
+	CreatedAt                   time.Time               `json:"created_at"`
+}
+
+type GenerateInput struct {
+	ConceptID string
+	AssetType workflows.AssetType
+}
+
+type Snapshot struct {
+	Prompts []PromptCandidate `json:"prompts"`
+}

internal/workflows/contracts.go

@@ -192,3 +192,52 @@ const (
 	UnlockReviewCard     UnlockKind = "review_card"
 	UnlockPortfolioEntry UnlockKind = "portfolio_entry"
 )
+
+type OntologyGap struct {
+	Track         string            `json:"track"`
+	MissingOrWeak []OntologyGapItem `json:"missing_or_weak"`
+}
+
+type OntologyGapItem struct {
+	Concept           ConceptRef      `json:"concept"`
+	GapType           OntologyGapType `json:"gap_type"`
+	Reason            string          `json:"reason"`
+	SupportingSources []EvidenceRef   `json:"supporting_sources"`
+	ProposedAction    GapAction       `json:"proposed_action"`
+}
+
+type OntologyGapType string
+
+const (
+	OntologyGapMissingPrerequisite OntologyGapType = "missing_prerequisite"
+	OntologyGapWeakEvidence        OntologyGapType = "weak_evidence"
+	OntologyGapOutdated            OntologyGapType = "outdated"
+	OntologyGapNeedsRubric         OntologyGapType = "needs_rubric"
+)
+
+type GapAction string
+
+const (
+	GapActionGenerateCandidate GapAction = "generate_candidate"
+	GapActionRequestSource     GapAction = "request_source"
+	GapActionHumanReview       GapAction = "human_review"
+)
+
+type TeachingAssetPrompt struct {
+	Concept                     ConceptRef    `json:"concept"`
+	AssetType                   AssetType     `json:"asset_type"`
+	Prompt                      string        `json:"prompt"`
+	SourceEvidence              []EvidenceRef `json:"source_evidence"`
+	ModelKey                    string        `json:"model_key"`
+	RequiresModelIDVerification bool          `json:"requires_model_id_verification"`
+	ReviewState                 string        `json:"review_state"`
+}
+
+type AssetType string
+
+const (
+	AssetDiagram       AssetType = "diagram"
+	AssetLessonSlice   AssetType = "lesson_slice"
+	AssetWorksheet     AssetType = "worksheet"
+	AssetInterviewCard AssetType = "interview_card"
+)

openspec/changes/bootstrap-job-tutor-platform/tasks.md

@@ -16,3 +16,4 @@
 - [x] 12. Implement evidence-backed learner memory ingestion and readback.
 - [x] 13. Implement evidence-backed readiness map and next challenge APIs.
 - [x] 14. Implement source-backed ontology material ingestion.
+- [x] 15. Implement source-backed teaching asset prompt candidates.