diff --git a/.ciagent/ARCHITECTURE.md b/.ciagent/ARCHITECTURE.md
index c475734..d6696f4 100644
--- a/.ciagent/ARCHITECTURE.md
+++ b/.ciagent/ARCHITECTURE.md
@@ -143,4 +143,112 @@ Each L1 module lives at `modules/l1/<name>/` with exactly two files:
 | `l1-cloudwatch` | Observability primitive |
 
 L1 modules are single-purpose, substrate-agnostic, max-depth-1 (per
-PROJECT.md Constraints). They do not compose with other L1s.
\ No newline at end of file
+PROJECT.md Constraints). They do not compose with other L1s.
+
+## L2 module schema + core scripts (Phase 03 research)
+
+### L2 manifest.yaml schema (D-020)
+
+```yaml
+name: l2-commodity-price-feed      # matches the folder name
+kind: l2                            # literal "l2"
+description: <one-line>
+l1s:                                # ordered list of L1 references
+  - name: l1-eks-fargate            # MUST match an existing L1 folder name
+    inputs:
+      cluster_name: price-feed-cluster
+      region: us-east-1
+      cpu_arch: arm64
+  - name: l1-lambda
+    inputs:
+      function_name: price-ingest
+      runtime: python3.11
+      handler: index.handler
+  # ... up to 5 L1 references per L2 (max-depth-5 per REQ-05; L2->L1 is depth 1)
+```
+
+L2s reference L1s **by name only** (no path); `mock_executor.sh` resolves
+the name to `modules/l1/<name>/`.
+
+### L2 list (fixed per REQ-04)
+
+| Folder | Description | L1s (per S&P Global Energy / Platts use cases) |
+|--------|-------------|------------------------------------------------|
+| `l2-invoice-service` | Billing + invoicing microservice | `l1-eks-fargate`, `l1-iam-role`, `l1-lambda`, `l1-sqs`, `l1-s3` |
+| `l2-commodity-price-feed` | Real-time price ingestion | `l1-eks-fargate`, `l1-lambda`, `l1-api-gateway`, `l1-eventbridge`, `l1-s3` |
+| `l2-energy-analytics-api` | Historical query API | `l1-eks-fargate`, `l1-api-gateway`, `l1-lambda`, `l1-s3`, `l1-cloudwatch` |
+| `l2-regulatory-reporting` | Compliance + reporting | `l1-eks-fargate`, `l1-iam-role`, `l1-lambda`, `l1-sqs`, `l1-s3` |
+
+Each L2 references exactly 5 L1s (within the max-depth-5 constraint; L2→L1
+is depth 1, so depth-5 is generous but the spec caps composition depth at
+5 — the count is 5 to demonstrate a realistic composed stack).
+
+### contract.yaml schema (D-021)
+
+```yaml
+stack: l2-commodity-price-feed      # MUST match an existing L2 folder name
+inputs:                              # top-level params for the L2 (optional)
+  environment: dev
+  owner: platform-team
+public-ingress: false                # bool; true triggers POLICY_VIOLATION:PUBLIC_INGRESS
+```
+
+The `public-ingress` key is the only policy-enforced field in Phase 03.
+Phase 04's pipeline reads `contract.yaml`, runs `policy_checker.py`, then
+`mock_executor.sh` to apply the L2.
+
+### state.json shape (D-022)
+
+`mock_executor.sh` writes `state.json` to its working directory:
+
+```json
+{
+  "l2": "l2-commodity-price-feed",
+  "l1s": [
+    {"name": "l1-eks-fargate", "applied": true, "exit_code": 0},
+    {"name": "l1-lambda", "applied": true, "exit_code": 0},
+    ...
+  ],
+  "contract": {
+    "stack": "l2-commodity-price-feed",
+    "inputs": {...},
+    "public-ingress": false
+  }
+}
+```
+
+### audit.json event + hash chain (D-023)
+
+`audit.json` is a JSON array of event objects. `evidence_writer.py`
+appends one event per call. Hash chain:
+
+1. Construct the event dict with `hash` set to empty string.
+2. Serialize via `json.dumps(event, sort_keys=True, separators=(",", ":"))` — canonical JSON (deterministic key order, no whitespace).
+3. Compute `hash = sha256(canonical_json.encode("utf-8")).hexdigest()`.
+4. Set `event["hash"] = hash`.
+5. Append to `audit.json`.
+
+Genesis event (when `audit.json` is empty or missing):
+
+```json
+{
+  "seq": 0,
+  "ts": "2026-07-21T13:00:00Z",
+  "stage": "genesis",
+  "event": "audit log initialized",
+  "prev_hash": "GENESIS",
+  "hash": "<sha256 of the canonical json of this event with hash empty>"
+}
+```
+
+Subsequent events: `seq = prev.seq + 1`, `prev_hash = prev.hash`.
+
+### Core script I/O contracts
+
+| Script | Input | Output | Exit |
+|--------|-------|--------|------|
+| `mock_executor.sh` | `<contract.yaml path>` (argv[1]); reads L2 manifest from `modules/l2/<contract.stack>/manifest.yaml` | writes `state.json` to cwd; prints per-L1 progress | 0 on all-L1s-pass; non-zero on any L1 failure |
+| `policy_checker.py` | `<contract.yaml path>` (argv[1]) | stdout: `POLICY_PASS` or `POLICY_VIOLATION:PUBLIC_INGRESS` | 0 on pass; 1 on violation |
+| `confidence_signal.py` | `<contract.yaml path>` (argv[1]); calls policy_checker | stdout: `{"score": 0.90|0.40, "reason": "..."}` | 0 always (per D-024; pipeline decides gate) |
+| `evidence_writer.py` | argv: `--stage <dev|qa|prod|finalize|genesis>` `--event "<text>"` `--audit <path to audit.json>` (default `./audit.json`) | appends event to audit.json; prints the new event's hash + seq | 0 on success; 1 on I/O error |
+| `l3b_agent_stub.py` | argv[1] = issue body text (or stdin if no argv); optional `-o <path>` (default stdout) | writes a `contract.yaml` (D-021 schema) with `stack` set by the D-008 keyword map | 0 on success; 1 on empty input |
\ No newline at end of file
diff --git a/.ciagent/PLAN.md b/.ciagent/PLAN.md
index e8482b3..f8d91ce 100644
--- a/.ciagent/PLAN.md
+++ b/.ciagent/PLAN.md
@@ -1,85 +1,102 @@
 ---
-phase: 02
-name: l1-modules
+phase: 03
+name: l2-modules-and-core-scripts
 milestone: v1.0
 milestone_type: feature
 status: planned
-requirements: [REQ-02, REQ-03]
+requirements: [REQ-04, REQ-05, REQ-06, REQ-07, REQ-08, REQ-11]
 must_haves:
-  - "All 8 L1 module folders exist under modules/l1/ with the exact names from REQ-02"
-  - "Each L1 has a manifest.yaml matching the schema in ARCHITECTURE.md (name, kind: l1, description, inputs: map of string keys)"
-  - "Each L1 has a mock_apply.sh that echoes '[L1: <name>] applying...', sleeps 1s, echoes '[L1: <name>] OK', exits 0 (D-007)"
-  - "All mock_apply.sh are executable (chmod +x) and bash -n clean"
-  - "All manifest.yaml files parse as valid YAML"
-  - "scripts/verify_phase02.sh passes: enumerates 8 L1s, validates each manifest, runs each mock_apply.sh, confirms exit 0 + expected output"
+  - "4 L2 module folders exist under modules/l2/ with exact names: l2-invoice-service, l2-commodity-price-feed, l2-energy-analytics-api, l2-regulatory-reporting"
+  - "Each L2 has a manifest.yaml matching the D-020 schema (name, kind: l2, description, l1s: list of {name, inputs: map})"
+  - "Each L2 references 5 L1s by name; all referenced L1 names exist in modules/l1/"
+  - "mock_executor.sh reads a contract.yaml, resolves the L2, invokes each L1 mock_apply.sh, writes state.json per D-022"
+  - "policy_checker.py exits 1 with 'POLICY_VIOLATION:PUBLIC_INGRESS' on public-ingress:true; exits 0 with 'POLICY_PASS' otherwise (D-025)"
+  - "confidence_signal.py prints {score, reason} JSON; score 0.90 on pass, 0.40 on policy fail (D-024)"
+  - "evidence_writer.py appends an event to audit.json with a valid canonical-JSON SHA-256 hash chain (D-023)"
+  - "l3b_agent_stub.py maps the Act 3 example issue text to l2-commodity-price-feed and emits a valid contract.yaml (D-026/D-008)"
+  - "scripts/verify_phase03.sh passes: validates all 4 L2s, runs each core script with a sample contract, confirms hash chain integrity"
 verification:
-  typecheck: "bash -n modules/l1/*/mock_apply.sh scripts/*.sh && python3 -c 'import yaml; [yaml.safe_load(open(f)) for f in glob.glob(\"modules/l1/*/manifest.yaml\")]'"
-  test: "scripts/verify_phase02.sh"
+  typecheck: "bash -n scripts/*.sh && python3 -m py_compile scripts/*.py && python3 -c 'import yaml, glob; [yaml.safe_load(open(f)) for f in glob.glob(\"modules/l2/*/manifest.yaml\")]'"
+  test: "scripts/verify_phase03.sh"
   build: no-op
 ---
 
-# Phase 02 — l1-modules PLAN
+# Phase 03 — l2-modules-and-core-scripts PLAN
 
 ## Goal
 
-Create the 8 L1 stub modules under `modules/l1/`. Each module has a
-`manifest.yaml` (declared inputs, flat string map per D-017) and a uniform
-`mock_apply.sh` (echo + 1s sleep + exit 0 per D-007/D-018). After this phase,
-Phase 03 can compose L1s into L2 modules and `mock_executor.sh` can iterate
-over an L2's L1 references.
+Create the 4 L2 composition modules and the 5 core scripts. After this
+phase, the demo has every primitive needed for Phase 04 to wire the
+pipeline and Phase 05 to render the evidence UI.
 
 ## Requirements covered
 
-- REQ-02: 8 L1 module folders exist (exact names)
-- REQ-03: each L1 has manifest.yaml + mock_apply.sh with the uniform behavior
+- REQ-04: 4 L2 modules under modules/l2/ composing L1s
+- REQ-05: L2s compose L1s, max depth 5
+- REQ-06: mock_executor.sh reads L2 + invokes L1s + writes state.json
+- REQ-07: policy_checker.py fails on public-ingress:true
+- REQ-08: confidence_signal.py 0.90/0.40 + gate ≥ 0.50
+- REQ-11: evidence_writer.py SHA-256 hash chain
 
-## Waves (vertical slices)
+## Waves (vertical slices, domain priority order)
 
-### Wave 1 — infra-stub-engineer (creates the 8 L1s)
+### Wave 1 — infra-stub-engineer (4 L2 manifests)
 
 **Tasks:**
 
-- **T-2.1** Create `modules/l1/l1-eks-fargate/{manifest.yaml, mock_apply.sh}`
-- **T-2.2** Create `modules/l1/l1-iam-role/{manifest.yaml, mock_apply.sh}`
-- **T-2.3** Create `modules/l1/l1-lambda/{manifest.yaml, mock_apply.sh}`
-- **T-2.4** Create `modules/l1/l1-api-gateway/{manifest.yaml, mock_apply.sh}`
-- **T-2.5** Create `modules/l1/l1-eventbridge/{manifest.yaml, mock_apply.sh}`
-- **T-2.6** Create `modules/l1/l1-sqs/{manifest.yaml, mock_apply.sh}`
-- **T-2.7** Create `modules/l1/l1-s3/{manifest.yaml, mock_apply.sh}`
-- **T-2.8** Create `modules/l1/l1-cloudwatch/{manifest.yaml, mock_apply.sh}`
+- **T-3.1** Create `modules/l2/l2-invoice-service/manifest.yaml` (L1s: l1-eks-fargate, l1-iam-role, l1-lambda, l1-sqs, l1-s3)
+- **T-3.2** Create `modules/l2/l2-commodity-price-feed/manifest.yaml` (L1s: l1-eks-fargate, l1-lambda, l1-api-gateway, l1-eventbridge, l1-s3)
+- **T-3.3** Create `modules/l2/l2-energy-analytics-api/manifest.yaml` (L1s: l1-eks-fargate, l1-api-gateway, l1-lambda, l1-s3, l1-cloudwatch)
+- **T-3.4** Create `modules/l2/l2-regulatory-reporting/manifest.yaml` (L1s: l1-eks-fargate, l1-iam-role, l1-lambda, l1-sqs, l1-s3)
 
-Each L1's `manifest.yaml` declares 1-3 plausible inputs for that primitive
-(e.g., `l1-s3` declares `bucket_name`, `region`, `retention_days`; `l1-iam-role`
-declares `role_name`, `trust_policy`). Each `mock_apply.sh` follows the exact
-uniform template from ARCHITECTURE.md.
+Each manifest declares plausible `inputs` per L1 (string map per D-017).
+Remove `modules/l2/.gitkeep` in T-3.1.
 
-**Files owned (territory):** `modules/l1/**`
+**Files owned:** `modules/l2/**`
 
-**Commits:** one per task, `---ci---` block has `phase: 2, status: plan-as-execute, persona: infra-stub-engineer, task: T-2.x, requirements.covered: [REQ-02, REQ-03]`.
+**Commits:** one per task, `phase: 3, status: plan-as-execute, persona: infra-stub-engineer, task: T-3.x, requirements.covered: [REQ-04, REQ-05]`.
 
-### Wave 2 — lead-developer (verification script + traceability)
+### Wave 2 — backend-engineer (5 core scripts)
 
 **Tasks:**
 
-- **T-2.9** Create `scripts/verify_phase02.sh`. It:
-  1. Enumerates `modules/l1/*/` and confirms exactly 8 folders with the 8 expected names.
-  2. For each L1: confirms `manifest.yaml` exists and parses as YAML with `name` matching the folder, `kind: l1`, and an `inputs:` map.
-  3. For each L1: confirms `mock_apply.sh` is executable, `bash -n` clean, runs in <2s, exits 0, and its stdout contains the `[L1: <name>] applying...` and `[L1: <name>] OK` markers.
-  4. Prints a PASS/FAIL summary; exits 0 on full success.
-- **T-2.10** Update `.ciagent/REQUIREMENTS.md` (REQ-02/03 → covered pending VERIFY) and `.ciagent/ROADMAP.md` (Phase 02 → executing). No README change.
+- **T-3.5** Create `scripts/policy_checker.py` — reads contract.yaml (argv[1]); if `public-ingress: true`, print `POLICY_VIOLATION:PUBLIC_INGRESS` and exit 1; else print `POLICY_PASS` and exit 0. Use only stdlib (yaml is available). Idempotent, no side effects.
+- **T-3.6** Create `scripts/confidence_signal.py` — reads contract.yaml (argv[1]); calls policy_checker as a subprocess; if pass → `{"score": 0.90, "reason": "POLICY_PASS"}`, if fail → `{"score": 0.40, "reason": "POLICY_VIOLATION:PUBLIC_INGRESS"}`. Print JSON to stdout. Exit 0 always.
+- **T-3.7** Create `scripts/evidence_writer.py` — argv flags `--stage`, `--event`, `--audit <path>` (default `./audit.json`). Loads audit.json (or empty list), computes the new event with canonical-JSON SHA-256 hash chain per D-023, appends, writes back atomically (write tmp + rename). Prints `{"seq": N, "hash": "..."}` to stdout. Genesis event automatically inserted if the file is empty/missing.
+- **T-3.8** Create `scripts/mock_executor.sh` — argv[1] = contract.yaml path. Reads contract.stack, resolves `modules/l2/<stack>/manifest.yaml`, iterates `l1s`, invokes `modules/l1/<name>/mock_apply.sh` for each, captures exit code, writes `state.json` per D-022. Exit 0 if all L1s exit 0; non-zero otherwise.
+- **T-3.9** Create `scripts/l3b_agent_stub.py` — argv[1] = issue body (or read stdin if absent); optional `-o <path>` (default stdout). Applies the D-008 keyword map; writes a contract.yaml (D-021 schema) with `stack` set to the mapped L2 name and a fixed `inputs:` map per stack. Exit 0 on success, 1 on empty input.
 
-**Files owned (territory):** `scripts/verify_phase02.sh`, `.ciagent/REQUIREMENTS.md`, `.ciagent/ROADMAP.md`
+**Files owned:** `scripts/policy_checker.py`, `scripts/confidence_signal.py`, `scripts/evidence_writer.py`, `scripts/mock_executor.sh`, `scripts/l3b_agent_stub.py`
 
-**Commits:** one per task, `---ci---` block has `phase: 2, status: plan-as-execute, persona: lead-developer, task: T-2.9/2.10`.
+**Commits:** one per task, `phase: 3, status: plan-as-execute, persona: backend-engineer, task: T-3.x, requirements.covered: [REQ-06/07/08/11/12]`.
+
+### Wave 3 — lead-developer (verify script + traceability)
+
+**Tasks:**
+
+- **T-3.10** Create `scripts/verify_phase03.sh`. Checks:
+  1. Exactly 4 L2 folders with the expected names.
+  2. Each L2 manifest.yaml parses, name matches folder, kind=l2, l1s is a list of 5 entries, all referenced L1 names exist in modules/l1/.
+  3. policy_checker.py on a passing contract → exit 0 + `POLICY_PASS`; on `public-ingress: true` contract → exit 1 + `POLICY_VIOLATION:PUBLIC_INGRESS`.
+  4. confidence_signal.py on passing contract → `{"score": 0.90, ...}`; on failing contract → `{"score": 0.40, ...}`. Both exit 0.
+  5. mock_executor.sh on a sample contract → writes state.json with l2 + l1s (all applied=true, exit_code=0) + contract fields.
+  6. evidence_writer.py: append 3 events to a temp audit.json; verify seq increments 0/1/2, prev_hash chain links, each hash matches a recompute.
+  7. l3b_agent_stub.py on the Act 3 example issue text ("We need to ingest natural gas prices from Platts...") → emits a contract.yaml with `stack: l2-commodity-price-feed`.
+- **T-3.11** Update `.ciagent/REQUIREMENTS.md` (REQ-04/05/06/07/08/11 → covered pending VERIFY) and `.ciagent/ROADMAP.md` (Phase 03 → executing).
+
+**Files owned:** `scripts/verify_phase03.sh`, `.ciagent/REQUIREMENTS.md`, `.ciagent/ROADMAP.md`
+
+**Commits:** one per task, `phase: 3, status: plan-as-execute, persona: lead-developer, task: T-3.10/3.11`.
 
 ## Wave ordering
 
-- Wave 1 (infra-stub-engineer) creates all 8 L1s. A single subagent gets all 8 tasks; it commits per task.
-- Wave 2 (lead-developer) adds the verify script and traceability after the L1s exist.
+- Wave 1 (infra-stub-engineer) creates the 4 L2 manifests first so mock_executor.sh has something to resolve.
+- Wave 2 (backend-engineer) builds the 5 core scripts. policy_checker + confidence_signal have no L2 dependency; mock_executor depends on Wave 1; l3b_agent_stub is independent.
+- Wave 3 (lead-developer) wires the verify script after both Waves 1 and 2 are complete.
 
-`backend-engineer`, `data-engineer`, `frontend-engineer` have 0 tasks this phase.
+`data-engineer` and `frontend-engineer` have 0 tasks this phase.
 
 ## Dependencies
 
-- Depends on Phase 01 (the `modules/l1/.gitkeep` from T-1.1 is replaced by real folders).
-- Phase 03 depends on this phase for L1 references in L2 compositions.
\ No newline at end of file
+- Depends on Phase 02 (L1 modules exist so mock_executor can invoke them and verify_phase03 can confirm L2 references resolve).
+- Phase 04 depends on this phase for the pipeline to call policy_checker, mock_executor, confidence_signal, evidence_writer, and for the issue workflow to call l3b_agent_stub.
\ No newline at end of file
diff --git a/.ciagent/PROJECT.md b/.ciagent/PROJECT.md
index 17057a4..693f59a 100644
--- a/.ciagent/PROJECT.md
+++ b/.ciagent/PROJECT.md
@@ -78,4 +78,11 @@ Build a runnable demo (Linux + GitHub/Gitea Actions) that walks executives throu
 | D-016 | Pages placeholder for Phase 01 is a minimal HTML stub (`<title>ACDL Evidence</title>` + "evidence stream coming soon"); full UI deferred to Phase 05 | Phase 01 success criterion is "Pages returns 200 with placeholder index.html" but Gitea has no Pages | Raw-URL HTTP 200 against `index.html` substitutes for the Pages check; full timeline UI built in Phase 05 |
 | D-017 | Each L1 `manifest.yaml` declares a single `inputs:` map of named string keys with descriptions; no nested types (substrate-agnostic, max-depth-1) | REQ-02/03 say "declared inputs"; spec forbids composition and cloud-specific types | Uniform, parseable schema that Phase 03's `mock_executor.sh` can read with python+yaml |
 | D-018 | L1 `mock_apply.sh` reads its own `manifest.yaml` for self-identification but ignores the input values (uniform stub per D-007) | D-007 mandates a literal echo + 1s sleep + exit 0; inputs are declared for traceability, not consumed | Predictable evidence events + clean separation from Phase 03 where L2s pass inputs to L1s |
-| D-019 | The 8 L1 names are fixed per REQ-02: `l1-eks-fargate`, `l1-iam-role`, `l1-lambda`, `l1-api-gateway`, `l1-eventbridge`, `l1-sqs`, `l1-s3`, `l1-cloudwatch` | REQ-02 literal | Phase 02 enumerates them exactly; no naming freedom |
\ No newline at end of file
+| D-019 | The 8 L1 names are fixed per REQ-02: `l1-eks-fargate`, `l1-iam-role`, `l1-lambda`, `l1-api-gateway`, `l1-eventbridge`, `l1-sqs`, `l1-s3`, `l1-cloudwatch` | REQ-02 literal | Phase 02 enumerates them exactly; no naming freedom |
+| D-020 | L2 `manifest.yaml` schema: `name`, `kind: l2`, `description`, `l1s:` (list of `{name, inputs: map}` entries). L2 references L1s by name (no path); inputs are string maps per L1 manifest declarations | REQ-04 says L2 "composes L1s"; REQ-05 caps depth at 5 (L2→L1 is depth 1) | mock_executor.sh reads `l1s:` and invokes each L1's `mock_apply.sh` |
+| D-021 | `contract.yaml` schema: `stack` (L2 name), `inputs` (string map for the L2's top-level params), optional `public-ingress: bool` (the policy violation key per REQ-07) | REQ-07 cites `public-ingress: true` as the forbidden key; REQ-08's confidence signal keys off policy pass/fail | Single flat schema drives both policy_checker and the mock_executor |
+| D-022 | `mock_executor.sh` writes `state.json` with shape `{"l2": "<name>", "l1s": [{"name":"...","applied":true,"exit_code":0}], "contract": <contract.yaml parsed>}` to the cwd; idempotent (overwrites) | REQ-06 says "writes state.json" but does not specify shape | Deterministic, parseable; Phase 05's evidence UI can include it in the audit trail |
+| D-023 | `evidence_writer.py` appends events to `audit.json` (a JSON array of event objects). Each event: `{"seq": N, "ts": <iso8601>, "stage": "dev|qa|prod|finalize", "event": "<string>", "prev_hash": "<sha256>", "hash": "<sha256 of canonical json of this event with hash field empty>"}`. The genesis event has `prev_hash: "GENESIS"` and `seq: 0` | D-005 mandates hash-chained ledger; canonical JSON for deterministic hashing | Visible tamper-evidence without overengineering; Phase 05 UI reads the array |
+| D-024 | `confidence_signal.py` reads `contract.yaml`, calls `policy_checker.py` (as a subprocess or import), returns base 0.90 on pass and 0.40 with reason code on policy failure; prints `{"score": 0.90|0.40, "reason": "<POLICY_VIOLATION:...|>"}` to stdout; exit 0 always | REQ-08 literal: base 0.90, drops to 0.40, gate ≥ 0.50 | Deterministic JSON output for the pipeline to consume |
+| D-025 | `policy_checker.py` reads `contract.yaml`, fails with exit code 1 and stdout `POLICY_VIOLATION:PUBLIC_INGRESS` if `public-ingress: true`; otherwise exits 0 with stdout `POLICY_PASS` | REQ-07 literal | Single source of policy truth; called by confidence_signal and the pipeline directly |
+| D-026 | `l3b_agent_stub.py` reads Issue body text from argv[1] (or stdin if no argv), applies the D-008 keyword map, writes a `contract.yaml` to stdout (or to `-o <path>`). Output contract uses the D-021 schema with `stack:` set to the mapped L2 name and a fixed `inputs:` map per L2 | D-008 + Act 3 example; L3B must produce the same contract format as L3A | Deterministic keyword parser; no external APIs |
\ No newline at end of file
diff --git a/.ciagent/REQUIREMENTS.md b/.ciagent/REQUIREMENTS.md
index 0334d1f..c2caa6e 100644
--- a/.ciagent/REQUIREMENTS.md
+++ b/.ciagent/REQUIREMENTS.md
@@ -60,15 +60,15 @@
 | REQ-01 | 1 | complete (v1.0.1) |
 | REQ-02 | 2 | complete (v1.0.2) |
 | REQ-03 | 2 | complete (v1.0.2) |
-| REQ-04 | 3 | pending |
-| REQ-05 | 3 | pending |
-| REQ-06 | 3 | pending |
-| REQ-07 | 3 | pending |
-| REQ-08 | 3 | pending |
+| REQ-04 | 3 | covered (pending VERIFY) |
+| REQ-05 | 3 | covered (pending VERIFY) |
+| REQ-06 | 3 | covered (pending VERIFY) |
+| REQ-07 | 3 | covered (pending VERIFY) |
+| REQ-08 | 3 | covered (pending VERIFY) |
 | REQ-09 | 1 | complete (v1.0.1) |
 | REQ-10 | 4 | partial (skeleton in Phase 01 v1.0.1; full impl in Phase 04) |
-| REQ-11 | 3 | pending |
-| REQ-12 | 4 | partial (skeleton in Phase 01 v1.0.1; full impl in Phase 04) |
+| REQ-11 | 3 | covered (pending VERIFY) |
+| REQ-12 | 4 | partial (skeleton in Phase 01 v1.0.1; l3b_agent_stub in Phase 03; full trigger wiring in Phase 04) |
 | REQ-13 | 5 | pending |
 | REQ-14 | 5 | pending |
 | REQ-15 | 5 | pending |
\ No newline at end of file
diff --git a/.ciagent/ROADMAP.md b/.ciagent/ROADMAP.md
index 9c20e25..01f031e 100644
--- a/.ciagent/ROADMAP.md
+++ b/.ciagent/ROADMAP.md
@@ -27,7 +27,7 @@ Five-phase breakdown to take ACDL from empty repo to a reproducible 4-act execut
 
 ### Phase 03 — l2-modules-and-core-scripts
 - **Description:** Create the 4 L2 compositions under `acdl/modules/l2/` referencing L1s, plus the 5 core scripts in `acdl/scripts/` (`mock_executor.sh`, `policy_checker.py`, `confidence_signal.py`, `evidence_writer.py`, `l3b_agent_stub.py`).
-- **Status:** not_started
+- **Status:** executing
 - **Depends on:** [2]
 - **Requirements:** REQ-04, REQ-05, REQ-06, REQ-07
 - **Success Criteria:**
diff --git a/modules/l2/.gitkeep b/modules/l2/.gitkeep
deleted file mode 100644
index e69de29..0000000
diff --git a/modules/l2/l2-commodity-price-feed/manifest.yaml b/modules/l2/l2-commodity-price-feed/manifest.yaml
new file mode 100644
index 0000000..38f9cb8
--- /dev/null
+++ b/modules/l2/l2-commodity-price-feed/manifest.yaml
@@ -0,0 +1,27 @@
+name: l2-commodity-price-feed
+kind: l2
+description: Real-time commodity price ingestion from Platts
+l1s:
+  - name: l1-eks-fargate
+    inputs:
+      cluster_name: price-feed-cluster
+      region: us-east-1
+      cpu_arch: arm64
+  - name: l1-lambda
+    inputs:
+      function_name: price-ingest
+      runtime: python3.11
+      handler: index.handler
+  - name: l1-api-gateway
+    inputs:
+      api_name: platts-price-api
+      stage_name: dev
+  - name: l1-eventbridge
+    inputs:
+      bus_name: price-events
+      rule_name: price-publish-rule
+  - name: l1-s3
+    inputs:
+      bucket_name: acdl-price-archive
+      region: us-east-1
+      retention_days: "90"
\ No newline at end of file
diff --git a/modules/l2/l2-energy-analytics-api/manifest.yaml b/modules/l2/l2-energy-analytics-api/manifest.yaml
new file mode 100644
index 0000000..a456faa
--- /dev/null
+++ b/modules/l2/l2-energy-analytics-api/manifest.yaml
@@ -0,0 +1,27 @@
+name: l2-energy-analytics-api
+kind: l2
+description: Historical energy analytics query API
+l1s:
+  - name: l1-eks-fargate
+    inputs:
+      cluster_name: analytics-cluster
+      region: us-east-1
+      cpu_arch: arm64
+  - name: l1-api-gateway
+    inputs:
+      api_name: energy-analytics-api
+      stage_name: dev
+  - name: l1-lambda
+    inputs:
+      function_name: analytics-query
+      runtime: python3.11
+      handler: index.handler
+  - name: l1-s3
+    inputs:
+      bucket_name: acdl-analytics-data
+      region: us-east-1
+      retention_days: "2555"
+  - name: l1-cloudwatch
+    inputs:
+      log_group_name: /acdl/analytics-api
+      metric_namespace: acdl/analytics
\ No newline at end of file
diff --git a/modules/l2/l2-invoice-service/manifest.yaml b/modules/l2/l2-invoice-service/manifest.yaml
new file mode 100644
index 0000000..e01f63f
--- /dev/null
+++ b/modules/l2/l2-invoice-service/manifest.yaml
@@ -0,0 +1,27 @@
+name: l2-invoice-service
+kind: l2
+description: Billing and invoicing microservice for energy trades
+l1s:
+  - name: l1-eks-fargate
+    inputs:
+      cluster_name: invoice-cluster
+      region: us-east-1
+      cpu_arch: arm64
+  - name: l1-iam-role
+    inputs:
+      role_name: invoice-service-role
+      trust_policy: '{"Version":"2012-10-17","Statement":[{"Effect":"Allow","Principal":{"Service":"eks.amazonaws.com"},"Action":"sts:AssumeRole"}]}'
+  - name: l1-lambda
+    inputs:
+      function_name: invoice-generator
+      runtime: python3.11
+      handler: index.handler
+  - name: l1-sqs
+    inputs:
+      queue_name: invoice-queue
+      visibility_timeout: "60"
+  - name: l1-s3
+    inputs:
+      bucket_name: acdl-invoice-archive
+      region: us-east-1
+      retention_days: "365"
\ No newline at end of file
diff --git a/modules/l2/l2-regulatory-reporting/manifest.yaml b/modules/l2/l2-regulatory-reporting/manifest.yaml
new file mode 100644
index 0000000..b64ab58
--- /dev/null
+++ b/modules/l2/l2-regulatory-reporting/manifest.yaml
@@ -0,0 +1,27 @@
+name: l2-regulatory-reporting
+kind: l2
+description: Regulatory compliance and reporting for energy trading
+l1s:
+  - name: l1-eks-fargate
+    inputs:
+      cluster_name: regulatory-cluster
+      region: us-east-1
+      cpu_arch: arm64
+  - name: l1-iam-role
+    inputs:
+      role_name: regulatory-reporting-role
+      trust_policy: '{"Version":"2012-10-17","Statement":[{"Effect":"Allow","Principal":{"Service":"eks.amazonaws.com"},"Action":"sts:AssumeRole"}]}'
+  - name: l1-lambda
+    inputs:
+      function_name: regulatory-reporter
+      runtime: python3.11
+      handler: index.handler
+  - name: l1-sqs
+    inputs:
+      queue_name: regulatory-queue
+      visibility_timeout: "120"
+  - name: l1-s3
+    inputs:
+      bucket_name: acdl-regulatory-archive
+      region: us-east-1
+      retention_days: "2555"
\ No newline at end of file
diff --git a/scripts/confidence_signal.py b/scripts/confidence_signal.py
new file mode 100755
index 0000000..d47168b
--- /dev/null
+++ b/scripts/confidence_signal.py
@@ -0,0 +1,55 @@
+#!/usr/bin/env python3
+"""confidence_signal.py — REQ-08 / D-024
+
+Reads a contract.yaml, invokes policy_checker.py as a subprocess, and emits
+a deterministic JSON confidence score.
+
+  policy pass  -> {"score": 0.90, "reason": "POLICY_PASS"}
+  policy fail  -> {"score": 0.40, "reason": "<violation code>"}
+
+Exit 0 ALWAYS (per D-024): the pipeline decides the gate, not this script's
+exit code.
+
+Input: argv[1] = path to a contract.yaml file.
+"""
+import json
+import os
+import subprocess
+import sys
+
+
+def main() -> int:
+    if len(sys.argv) < 2:
+        print("usage: confidence_signal.py <contract.yaml>", file=sys.stderr)
+        return 1
+
+    contract_path = sys.argv[1]
+
+    # Resolve policy_checker.py relative to this script so it works regardless
+    # of cwd. Use python3 + script path (not ./) per the contract.
+    here = os.path.dirname(os.path.abspath(__file__))
+    policy_checker = os.path.join(here, "policy_checker.py")
+
+    proc = subprocess.run(
+        ["python3", policy_checker, contract_path],
+        capture_output=True,
+        text=True,
+    )
+
+    if proc.returncode == 0:
+        score = "0.90"
+        # POLICY_PASS is the expected stdout; strip any trailing whitespace.
+        reason = proc.stdout.strip() or "POLICY_PASS"
+    else:
+        score = "0.40"
+        # The violation code (e.g. "POLICY_VIOLATION:PUBLIC_INGRESS") is on stdout.
+        reason = proc.stdout.strip() or "POLICY_VIOLATION:UNKNOWN"
+
+    # Emit with literal score (two-decimal form per the contract) and a quoted
+    # reason. Constructed manually so json.dumps does not collapse 0.90 -> 0.9.
+    print('{"score": ' + score + ', "reason": ' + json.dumps(reason) + '}')
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
\ No newline at end of file
diff --git a/scripts/evidence_writer.py b/scripts/evidence_writer.py
new file mode 100755
index 0000000..09472bc
--- /dev/null
+++ b/scripts/evidence_writer.py
@@ -0,0 +1,123 @@
+#!/usr/bin/env python3
+"""evidence_writer.py — REQ-11 / D-023 / D-005
+
+Appends a hash-chained event to audit.json.
+
+Each event: {"seq": N, "ts": <iso8601 UTC>, "stage": "...", "event": "...",
+             "prev_hash": "<sha256 or GENESIS>", "hash": "<sha256 of canonical json of this event with hash empty>"}
+
+Hash chain (D-023):
+  1. Build event dict with hash = "" (empty string).
+  2. canonical = json.dumps(event, sort_keys=True, separators=(",", ":"))
+  3. hash = sha256(canonical.encode("utf-8")).hexdigest()
+  4. event["hash"] = hash
+  5. append to audit.json
+
+Auto-genesis: if audit.json is empty/missing and --stage is not "genesis",
+a genesis event (seq 0, prev_hash "GENESIS") is inserted first.
+
+Input:
+  --stage <dev|qa|prod|finalize|genesis>  (required)
+  --event "<text>"                        (required)
+  --audit <path>                          (optional, default ./audit.json)
+Output: stdout {"seq": N, "hash": "..."}
+Exit:   0 on success, 1 on I/O error.
+"""
+import argparse
+import datetime
+import hashlib
+import json
+import os
+import sys
+
+GENESIS_EVENT_TEXT = "audit log initialized"
+
+
+def now_iso8601_utc() -> str:
+    return datetime.datetime.now(datetime.timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+
+
+def compute_hash(event: dict) -> str:
+    """Compute the sha256 hash of an event using canonical JSON (D-023)."""
+    tmp = dict(event)
+    tmp["hash"] = ""
+    canonical = json.dumps(tmp, sort_keys=True, separators=(",", ":"))
+    return hashlib.sha256(canonical.encode("utf-8")).hexdigest()
+
+
+def make_event(seq: int, stage: str, event_text: str, prev_hash: str) -> dict:
+    event = {
+        "seq": seq,
+        "ts": now_iso8601_utc(),
+        "stage": stage,
+        "event": event_text,
+        "prev_hash": prev_hash,
+        "hash": "",
+    }
+    event["hash"] = compute_hash(event)
+    return event
+
+
+def load_audit(audit_path: str) -> list:
+    if not os.path.exists(audit_path):
+        return []
+    try:
+        with open(audit_path, "r", encoding="utf-8") as fh:
+            data = json.load(fh)
+    except (json.JSONDecodeError, ValueError):
+        return []
+    if not isinstance(data, list):
+        return []
+    return data
+
+
+def atomic_write(audit_path: str, data: list) -> None:
+    tmp_path = audit_path + ".tmp"
+    with open(tmp_path, "w", encoding="utf-8") as fh:
+        json.dump(data, fh, indent=2)
+        fh.write("\n")
+    os.replace(tmp_path, audit_path)
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Append a hash-chained event to audit.json")
+    parser.add_argument("--stage", required=True,
+                        choices=["dev", "qa", "prod", "finalize", "genesis"])
+    parser.add_argument("--event", required=True)
+    parser.add_argument("--audit", default="./audit.json")
+    args = parser.parse_args()
+
+    events = load_audit(args.audit)
+
+    # Auto-genesis: if the log is empty and the caller did not ask for a
+    # genesis event, seed one first.
+    if len(events) == 0 and args.stage != "genesis":
+        genesis = make_event(seq=0, stage="genesis", event_text=GENESIS_EVENT_TEXT,
+                             prev_hash="GENESIS")
+        events.append(genesis)
+
+    # Determine the new seq + prev_hash.
+    if events:
+        last = events[-1]
+        seq = last["seq"] + 1
+        prev_hash = last["hash"]
+    else:
+        seq = 0
+        prev_hash = "GENESIS"
+
+    new_event = make_event(seq=seq, stage=args.stage, event_text=args.event,
+                           prev_hash=prev_hash)
+    events.append(new_event)
+
+    try:
+        atomic_write(args.audit, events)
+    except OSError as exc:
+        print(f"evidence_writer: I/O error: {exc}", file=sys.stderr)
+        return 1
+
+    print(json.dumps({"seq": new_event["seq"], "hash": new_event["hash"]}))
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
\ No newline at end of file
diff --git a/scripts/l3b_agent_stub.py b/scripts/l3b_agent_stub.py
new file mode 100755
index 0000000..bf1c93f
--- /dev/null
+++ b/scripts/l3b_agent_stub.py
@@ -0,0 +1,118 @@
+#!/usr/bin/env python3
+"""l3b_agent_stub.py — D-008 / D-026 / D-021
+
+Parses a GitHub/Gitea Issue body by keywords and emits a contract.yaml that
+selects an L2 stack. This is the agentic (L3B) entry surface: deterministic
+keyword matching, no external AI APIs.
+
+D-008 keyword map (priority order — first match wins):
+  gas, price, ingest, data-lake        -> l2-commodity-price-feed
+  invoice, billing                     -> l2-invoice-service
+  analytics, historical, query         -> l2-energy-analytics-api
+  regulatory, compliance, reporting, trading
+                                       -> l2-regulatory-reporting
+  (no match)                           -> l2-invoice-service  (fallback)
+
+Output contract.yaml (D-021 schema):
+  stack: <mapped L2 name>
+  inputs:
+    environment: dev
+    owner: citizen-developer
+    source: l3b-agent-stub
+  public-ingress: false
+
+Input:
+  argv[1] = issue body text (or stdin if argv[1] absent/empty)
+  -o <path> = write the contract to a file (default: stdout)
+Exit:
+  0 on success, 1 on empty input
+"""
+import sys
+
+
+# Ordered keyword groups -> L2 stack mapping (D-008). First match wins.
+KEYWORD_MAP = [
+    (("gas", "price", "ingest", "data-lake"), "l2-commodity-price-feed"),
+    (("invoice", "billing"), "l2-invoice-service"),
+    (("analytics", "historical", "query"), "l2-energy-analytics-api"),
+    (("regulatory", "compliance", "reporting", "trading"), "l2-regulatory-reporting"),
+]
+
+FALLBACK_STACK = "l2-invoice-service"
+
+
+def map_issue_to_stack(text: str) -> str:
+    lowered = text.lower()
+    for keywords, stack in KEYWORD_MAP:
+        for kw in keywords:
+            if kw in lowered:
+                return stack
+    return FALLBACK_STACK
+
+
+def render_contract(stack: str) -> str:
+    # Fixed-schema YAML (D-021). Emitted as text (no yaml dependency needed).
+    return (
+        f"stack: {stack}\n"
+        "inputs:\n"
+        "  environment: dev\n"
+        "  owner: citizen-developer\n"
+        "  source: l3b-agent-stub\n"
+        "public-ingress: false\n"
+    )
+
+
+def read_issue_body(args: list) -> str:
+    """Read issue body from args[0] (already-stripped argv, no script name)
+    or stdin. Empty -> error."""
+    if len(args) >= 1 and args[0].strip():
+        return args[0]
+    # Fall back to stdin if argv body is absent or empty.
+    if not sys.stdin.isatty():
+        data = sys.stdin.read()
+        if data.strip():
+            return data
+    return ""
+
+
+def parse_output_flag(argv: list):
+    """Extract -o <path> from argv (returns (rest, output_path))."""
+    output_path = None
+    rest = []
+    i = 1
+    while i < len(argv):
+        arg = argv[i]
+        if arg == "-o":
+            if i + 1 < len(argv):
+                output_path = argv[i + 1]
+                i += 2
+                continue
+            else:
+                print("l3b_agent_stub: -o requires a path argument", file=sys.stderr)
+                sys.exit(1)
+        rest.append(arg)
+        i += 1
+    return rest, output_path
+
+
+def main() -> int:
+    rest, output_path = parse_output_flag(sys.argv)
+    body = read_issue_body(rest)
+    if not body.strip():
+        print("l3b_agent_stub: empty issue body (no argv[1] and no stdin)", file=sys.stderr)
+        return 1
+
+    stack = map_issue_to_stack(body)
+    contract = render_contract(stack)
+
+    if output_path:
+        with open(output_path, "w", encoding="utf-8") as fh:
+            fh.write(contract)
+    else:
+        sys.stdout.write(contract)
+
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
\ No newline at end of file
diff --git a/scripts/mock_executor.sh b/scripts/mock_executor.sh
new file mode 100755
index 0000000..df02770
--- /dev/null
+++ b/scripts/mock_executor.sh
@@ -0,0 +1,126 @@
+#!/usr/bin/env bash
+# mock_executor.sh — REQ-06 / D-022
+#
+# Reads a contract.yaml, resolves the L2 composition, invokes each L1's
+# mock_apply.sh in order, and writes state.json to the current working
+# directory.
+#
+# Input: argv[1] = path to a contract.yaml file.
+# Output:
+#   - stdout: per-L1 progress (echoed from each mock_apply.sh)
+#   - state.json in cwd: {"l2": "...", "l1s": [...], "contract": {...}}
+# Exit:
+#   0 if all L1s exit 0; 1 if any L1 exited non-zero (state.json is still
+#   written with the recorded exit codes).
+set -euo pipefail
+
+if [[ $# -lt 1 ]]; then
+  echo "usage: mock_executor.sh <contract.yaml>" >&2
+  exit 1
+fi
+
+CONTRACT_PATH="$1"
+
+if [[ ! -f "$CONTRACT_PATH" ]]; then
+  echo "contract not found: $CONTRACT_PATH" >&2
+  exit 1
+fi
+
+# --- Parse the contract (stack + full contract dict) via python3 + yaml. ---
+# Emit stack on line 1 and the full contract JSON on line 2, then read both
+# lines into separate bash variables (so the JSON's internal spaces survive).
+CONTRACT_PARSED=$(python3 - "$CONTRACT_PATH" <<'PY'
+import sys, json, yaml
+path = sys.argv[1]
+with open(path, "r", encoding="utf-8") as fh:
+    contract = yaml.safe_load(fh)
+if not isinstance(contract, dict):
+    sys.stderr.write("contract is not a mapping\n")
+    sys.exit(2)
+stack = contract.get("stack", "")
+# Use a compact JSON (no spaces) so the single-line contract survives bash
+# variable capture cleanly.
+print(stack)
+print(json.dumps(contract, sort_keys=True, separators=(",", ":")))
+PY
+)
+
+STACK=$(printf '%s\n' "$CONTRACT_PARSED" | sed -n '1p')
+CONTRACT_JSON=$(printf '%s\n' "$CONTRACT_PARSED" | sed -n '2p')
+
+if [[ -z "$STACK" ]]; then
+  echo "contract missing 'stack' key" >&2
+  exit 1
+fi
+
+# --- Resolve the L2 manifest. ---
+L2_MANIFEST="modules/l2/${STACK}/manifest.yaml"
+if [[ ! -f "$L2_MANIFEST" ]]; then
+  echo "L2_NOT_FOUND: ${STACK}" >&2
+  exit 1
+fi
+
+# --- Read the L2's l1s: list (ordered names) via python. ---
+L1_NAMES_JSON=$(python3 - "$L2_MANIFEST" <<'PY'
+import sys, json, yaml
+path = sys.argv[1]
+with open(path, "r", encoding="utf-8") as fh:
+    manifest = yaml.safe_load(fh)
+l1s = manifest.get("l1s", []) if isinstance(manifest, dict) else []
+names = [entry.get("name", "") for entry in l1s if isinstance(entry, dict)]
+print(json.dumps(names))
+PY
+)
+
+# --- Invoke each L1's mock_apply.sh in order, recording exit codes. ---
+# Build the l1s results array in JSON via python, appending as we go.
+RESULTS_JSON="[]"
+
+ALL_OK=0
+while IFS= read -r L1_NAME; do
+  L1_SCRIPT="modules/l1/${L1_NAME}/mock_apply.sh"
+  if [[ ! -f "$L1_SCRIPT" ]]; then
+    echo "L1_NOT_FOUND: ${L1_NAME}" >&2
+    exit 1
+  fi
+
+  # Capture stdout + exit code. stderr passes through.
+  L1_OUT=$(bash "$L1_SCRIPT")
+  L1_RC=$?
+
+  # Echo the L1's stdout so the pipeline sees the progress lines.
+  printf '%s\n' "$L1_OUT"
+
+  # Record {"name": ..., "applied": true, "exit_code": ...}.
+  RESULTS_JSON=$(python3 - "$RESULTS_JSON" "$L1_NAME" "$L1_RC" <<'PY'
+import sys, json
+results = json.loads(sys.argv[1])
+name = sys.argv[2]
+rc = int(sys.argv[3])
+results.append({"name": name, "applied": True, "exit_code": rc})
+print(json.dumps(results))
+PY
+)
+
+  if [[ $L1_RC -ne 0 ]]; then
+    ALL_OK=1
+  fi
+done < <(python3 -c "import sys, json; print('\n'.join(json.loads(sys.argv[1])))" "$L1_NAMES_JSON")
+
+# --- Write state.json to the current working directory (D-022). ---
+python3 - "$RESULTS_JSON" "$STACK" "$CONTRACT_JSON" <<'PY'
+import sys, json
+results = json.loads(sys.argv[1])
+stack = sys.argv[2]
+contract = json.loads(sys.argv[3])
+state = {
+    "l2": stack,
+    "l1s": results,
+    "contract": contract,
+}
+with open("state.json", "w", encoding="utf-8") as fh:
+    json.dump(state, fh, indent=2)
+    fh.write("\n")
+PY
+
+exit "$ALL_OK"
\ No newline at end of file
diff --git a/scripts/policy_checker.py b/scripts/policy_checker.py
new file mode 100755
index 0000000..59fe163
--- /dev/null
+++ b/scripts/policy_checker.py
@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+"""policy_checker.py — REQ-07 / D-025
+
+Reads a contract.yaml and enforces the single Phase-03 policy rule:
+`public-ingress: true` is forbidden.
+
+Input:  argv[1] = path to a contract.yaml file.
+Output: stdout "POLICY_PASS" or "POLICY_VIOLATION:PUBLIC_INGRESS"
+Exit:   0 on pass, 1 on violation.
+
+Idempotent, no side effects (no file writes). Treats an absent or falsy
+`public-ingress` key as a pass.
+"""
+import sys
+import yaml
+
+
+def main() -> int:
+    if len(sys.argv) < 2:
+        print("usage: policy_checker.py <contract.yaml>", file=sys.stderr)
+        return 2
+
+    contract_path = sys.argv[1]
+
+    try:
+        with open(contract_path, "r", encoding="utf-8") as fh:
+            contract = yaml.safe_load(fh)
+    except FileNotFoundError:
+        print(f"contract not found: {contract_path}", file=sys.stderr)
+        return 2
+    except yaml.YAMLError as exc:
+        print(f"invalid yaml: {exc}", file=sys.stderr)
+        return 2
+
+    # Treat missing/non-mapping as no policy violation.
+    if not isinstance(contract, dict):
+        print("POLICY_PASS")
+        return 0
+
+    public_ingress = contract.get("public-ingress", False)
+
+    if public_ingress is True:
+        print("POLICY_VIOLATION:PUBLIC_INGRESS")
+        return 1
+
+    print("POLICY_PASS")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())
\ No newline at end of file
diff --git a/scripts/verify_phase03.sh b/scripts/verify_phase03.sh
new file mode 100755
index 0000000..83cccf0
--- /dev/null
+++ b/scripts/verify_phase03.sh
@@ -0,0 +1,240 @@
+#!/usr/bin/env bash
+# Phase 03 verification script.
+# Confirms the 4 L2 modules and the 5 core scripts conform to their contracts.
+#
+# Usage: scripts/verify_phase03.sh
+# Exit codes: 0 = all checks passed; 1 = one or more checks failed.
+
+set -uo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+cd "$ROOT"
+
+fail_count=0
+pass() { printf '  [PASS] %s\n' "$1"; }
+fail() { printf '  [FAIL] %s\n' "$1"; fail_count=$((fail_count + 1)); }
+
+# Expected L2 names per REQ-04.
+EXPECTED_L2S=(
+  l2-invoice-service
+  l2-commodity-price-feed
+  l2-energy-analytics-api
+  l2-regulatory-reporting
+)
+
+echo "== Phase 03 verification =="
+echo "Root: ${ROOT}"
+echo
+
+# --- Check 1: exactly 4 L2 folders with the expected names ---
+echo "-- Check 1: 4 L2 folders with expected names --"
+actual=$(ls modules/l2/ 2>/dev/null | sort | tr '\n' ' ')
+expected=$(printf '%s\n' "${EXPECTED_L2S[@]}" | sort | tr '\n' ' ')
+if [ "$actual" = "$expected" ]; then
+  pass "exactly 4 L2 folders present and named correctly"
+else
+  fail "L2 folder list mismatch"
+  echo "    expected: $expected"
+  echo "    actual:   $actual"
+fi
+
+# --- Check 2: each L2 manifest.yaml validates + references 5 existing L1s ---
+echo "-- Check 2: L2 manifests reference 5 existing L1s --"
+l2_validate=$(python3 << 'PYEOF' || true
+import yaml, glob, os, sys
+ok = True
+l1s = set(os.listdir('modules/l1'))
+for f in sorted(glob.glob('modules/l2/*/manifest.yaml')):
+    d = yaml.safe_load(open(f))
+    folder = os.path.basename(os.path.dirname(f))
+    problems = []
+    if d.get('name') != folder: problems.append(f"name != {folder}")
+    if d.get('kind') != 'l2': problems.append("kind != l2")
+    refs = [x.get('name') for x in d.get('l1s', [])]
+    if len(refs) != 5: problems.append(f"expected 5 l1s, got {len(refs)}")
+    unknown = [r for r in refs if r not in l1s]
+    if unknown: problems.append(f"unknown L1 refs: {unknown}")
+    # each l1 entry must have an inputs: map
+    for x in d.get('l1s', []):
+        if not isinstance(x.get('inputs'), dict): problems.append(f"l1 {x.get('name')} missing inputs map")
+    status = 'OK' if not problems else 'FAIL: ' + '; '.join(problems)
+    print(f'  [{status}] {f}')
+    if problems: ok = False
+sys.exit(0 if ok else 1)
+PYEOF
+)
+echo "$l2_validate"
+if [ "$l2_validate" = "" ] || echo "$l2_validate" | grep -q FAIL; then
+  if ! echo "$l2_validate" | grep -q PASS; then
+    fail "one or more L2 manifests invalid (see above)"
+  fi
+else
+  pass "all 4 L2 manifests valid"
+fi
+# Re-run for the explicit pass/fail count
+python3 << 'PYEOF' > /tmp/l2_check.txt 2>&1 || true
+import yaml, glob, os, sys
+ok = True
+l1s = set(os.listdir('modules/l1'))
+for f in sorted(glob.glob('modules/l2/*/manifest.yaml')):
+    d = yaml.safe_load(open(f))
+    folder = os.path.basename(os.path.dirname(f))
+    if d.get('name') != folder: ok = False
+    if d.get('kind') != 'l2': ok = False
+    refs = [x.get('name') for x in d.get('l1s', [])]
+    if len(refs) != 5: ok = False
+    if any(r not in l1s for r in refs): ok = False
+    for x in d.get('l1s', []):
+        if not isinstance(x.get('inputs'), dict): ok = False
+sys.exit(0 if ok else 1)
+PYEOF
+if [ $? -eq 0 ]; then pass "all 4 L2 manifests pass structural + reference checks"; else fail "L2 manifest structural check"; fi
+
+# --- Check 3: typecheck (bash -n + py_compile + yaml load) ---
+echo "-- Check 3: typecheck --"
+if bash -n scripts/mock_executor.sh; then pass "bash -n mock_executor.sh"; else fail "bash -n mock_executor.sh"; fi
+if python3 -m py_compile scripts/policy_checker.py scripts/confidence_signal.py scripts/evidence_writer.py scripts/l3b_agent_stub.py 2>/dev/null; then
+  pass "py_compile all 4 python scripts"
+else
+  fail "py_compile"
+fi
+if python3 -c "import yaml, glob; [yaml.safe_load(open(f)) for f in glob.glob('modules/l2/*/manifest.yaml')]" 2>/dev/null; then
+  pass "yaml load all L2 manifests"
+else
+  fail "yaml load L2 manifests"
+fi
+
+# --- Check 4: policy_checker (D-025) ---
+echo "-- Check 4: policy_checker behavior (D-025) --"
+WORK="$(mktemp -d)"
+trap 'rm -rf "$WORK" "$ROOT/tmp_pass_contract.yaml" "$ROOT/tmp_fail_contract.yaml" "$ROOT/state.json" 2>/dev/null || true' EXIT
+printf 'stack: l2-commodity-price-feed\npublic-ingress: false\n' > "$WORK/pass.yaml"
+printf 'stack: l2-regulatory-reporting\npublic-ingress: true\n' > "$WORK/fail.yaml"
+out=$(python3 scripts/policy_checker.py "$WORK/pass.yaml" 2>&1); rc=$?
+if [ "$out" = "POLICY_PASS" ] && [ "$rc" = "0" ]; then
+  pass "policy_checker pass contract -> POLICY_PASS exit 0"
+else
+  fail "policy_checker pass contract: got '$out' exit=$rc"
+fi
+out=$(python3 scripts/policy_checker.py "$WORK/fail.yaml" 2>&1); rc=$?
+if [ "$out" = "POLICY_VIOLATION:PUBLIC_INGRESS" ] && [ "$rc" = "1" ]; then
+  pass "policy_checker fail contract -> POLICY_VIOLATION:PUBLIC_INGRESS exit 1"
+else
+  fail "policy_checker fail contract: got '$out' exit=$rc"
+fi
+
+# --- Check 5: confidence_signal (D-024) ---
+echo "-- Check 5: confidence_signal behavior (D-024) --"
+out=$(python3 scripts/confidence_signal.py "$WORK/pass.yaml" 2>&1); rc=$?
+if echo "$out" | grep -q '"score": 0.90' && [ "$rc" = "0" ]; then
+  pass "confidence_signal pass -> score 0.90 exit 0"
+else
+  fail "confidence_signal pass: got '$out' exit=$rc"
+fi
+out=$(python3 scripts/confidence_signal.py "$WORK/fail.yaml" 2>&1); rc=$?
+if echo "$out" | grep -q '"score": 0.40' && [ "$rc" = "0" ]; then
+  pass "confidence_signal fail -> score 0.40 exit 0"
+else
+  fail "confidence_signal fail: got '$out' exit=$rc"
+fi
+
+# --- Check 6: evidence_writer hash chain (D-023) ---
+echo "-- Check 6: evidence_writer hash chain (D-023) --"
+rm -f "$WORK/audit.json"
+python3 scripts/evidence_writer.py --stage dev --event "dev start" --audit "$WORK/audit.json" > /dev/null
+python3 scripts/evidence_writer.py --stage qa --event "qa approved" --audit "$WORK/audit.json" > /dev/null
+python3 scripts/evidence_writer.py --stage prod --event "prod approved" --audit "$WORK/audit.json" > /dev/null
+chain_ok=$(python3 << PYEOF
+import json, hashlib, sys
+try:
+    events = json.load(open("$WORK/audit.json"))
+    assert len(events) == 4, f"expected 4 (genesis + 3), got {len(events)}"
+    assert events[0]['prev_hash'] == 'GENESIS', "genesis prev_hash"
+    for i in range(1, len(events)):
+        assert events[i]['prev_hash'] == events[i-1]['hash'], f"chain break at {i}"
+        e = dict(events[i]); h = e.pop('hash'); e['hash'] = ''
+        canon = json.dumps(e, sort_keys=True, separators=(',',':'))
+        assert hashlib.sha256(canon.encode()).hexdigest() == h, f"hash mismatch at {i}"
+    print("OK")
+except AssertionError as ex:
+    print(f"FAIL: {ex}")
+    sys.exit(1)
+PYEOF
+)
+if [ "$chain_ok" = "OK" ]; then
+  pass "evidence_writer: 4 events, GENESIS + 3, chain links + hashes valid"
+else
+  fail "evidence_writer chain: $chain_ok"
+fi
+
+# --- Check 7: mock_executor (D-022) ---
+echo "-- Check 7: mock_executor writes state.json (D-022) --"
+rm -f "$ROOT/state.json"
+out=$(bash scripts/mock_executor.sh "$WORK/pass.yaml" 2>&1); rc=$?
+if [ "$rc" != "0" ]; then
+  fail "mock_executor exit $rc (expected 0)"
+else
+  me_ok=$(python3 << PYEOF
+import json, sys
+try:
+    s = json.load(open("$ROOT/state.json"))
+    assert s['l2'] == 'l2-commodity-price-feed', f"l2 mismatch: {s.get('l2')}"
+    assert 'l1s' in s and len(s['l1s']) == 5, f"expected 5 l1s, got {len(s.get('l1s', []))}"
+    assert all(x['applied'] is True and x['exit_code'] == 0 for x in s['l1s']), "l1 not all applied+0"
+    assert 'contract' in s, "missing contract field"
+    print("OK")
+except Exception as ex:
+    print(f"FAIL: {ex}")
+    sys.exit(1)
+PYEOF
+)
+  if [ "$me_ok" = "OK" ]; then
+    pass "mock_executor: state.json with l2 + 5 l1s (all exit 0) + contract"
+  else
+    fail "mock_executor state.json: $me_ok"
+  fi
+fi
+rm -f "$ROOT/state.json"
+
+# --- Check 8: l3b_agent_stub D-008 keyword map ---
+echo "-- Check 8: l3b_agent_stub keyword map (D-008) --"
+act3=$(python3 scripts/l3b_agent_stub.py "We need to ingest natural gas prices from Platts and report on compliance." 2>&1)
+if echo "$act3" | grep -q 'stack: l2-commodity-price-feed'; then
+  pass "l3b Act 3 example -> l2-commodity-price-feed"
+else
+  fail "l3b Act 3 example: got '$act3'"
+fi
+fallback=$(python3 scripts/l3b_agent_stub.py "please deploy something" 2>&1)
+if echo "$fallback" | grep -q 'stack: l2-invoice-service'; then
+  pass "l3b fallback (no keywords) -> l2-invoice-service"
+else
+  fail "l3b fallback: got '$fallback'"
+fi
+regulatory=$(python3 scripts/l3b_agent_stub.py "regulatory compliance reporting for trading desk" 2>&1)
+if echo "$regulatory" | grep -q 'stack: l2-regulatory-reporting'; then
+  pass "l3b regulatory keywords -> l2-regulatory-reporting"
+else
+  fail "l3b regulatory: got '$regulatory'"
+fi
+invoice=$(python3 scripts/l3b_agent_stub.py "monthly invoice and billing reconciliation" 2>&1)
+if echo "$invoice" | grep -q 'stack: l2-invoice-service'; then
+  pass "l3b invoice keywords -> l2-invoice-service"
+else
+  fail "l3b invoice: got '$invoice'"
+fi
+analytics=$(python3 scripts/l3b_agent_stub.py "historical analytics and query API" 2>&1)
+if echo "$analytics" | grep -q 'stack: l2-energy-analytics-api'; then
+  pass "l3b analytics keywords -> l2-energy-analytics-api"
+else
+  fail "l3b analytics: got '$analytics'"
+fi
+
+echo
+echo "== Summary =="
+if [ "$fail_count" -eq 0 ]; then
+  echo "Phase 03 verification PASSED (4 L2s + 5 core scripts, all checks ok)"
+  exit 0
+else
+  echo "Phase 03 verification FAILED (${fail_count} check(s) failed)"
+  exit 1
+fi
\ No newline at end of file