diff --git a/adaptive_pricing_core/__init__.py b/adaptive_pricing_core/__init__.py
new file mode 100644
index 0000000..bce172b
--- /dev/null
+++ b/adaptive_pricing_core/__init__.py
@@ -0,0 +1,21 @@
+from .pricing_models import (
+    ChargeComponent,
+    Commitment,
+    PricingModel,
+    PricingModelStatus,
+    TunableParameter,
+    load_pricing_models,
+    validate_pricing_catalog,
+    validate_pricing_model,
+)
+
+__all__ = [
+    "ChargeComponent",
+    "Commitment",
+    "PricingModel",
+    "PricingModelStatus",
+    "TunableParameter",
+    "load_pricing_models",
+    "validate_pricing_catalog",
+    "validate_pricing_model",
+]
diff --git a/adaptive_pricing_core/pricing_models.py b/adaptive_pricing_core/pricing_models.py
new file mode 100644
index 0000000..f1acf6c
--- /dev/null
+++ b/adaptive_pricing_core/pricing_models.py
@@ -0,0 +1,323 @@
+from __future__ import annotations
+
+import json
+from dataclasses import dataclass, field
+from decimal import Decimal
+from pathlib import Path
+from typing import Any, Literal
+
+PricingModelStatus = Literal["active", "candidate", "retired"]
+ChargeComponentKind = Literal[
+    "access",
+    "setup",
+    "usage",
+    "support",
+    "discount",
+    "risk_adjustment",
+]
+ParameterClass = Literal[
+    "fixed",
+    "seller_controlled",
+    "customer_tunable",
+    "calculated",
+    "constrained",
+    "provider",
+]
+
+_ALLOWED_COMPONENT_KINDS = {
+    "access",
+    "setup",
+    "usage",
+    "support",
+    "discount",
+    "risk_adjustment",
+}
+_ALLOWED_PARAMETER_CLASSES = {
+    "fixed",
+    "seller_controlled",
+    "customer_tunable",
+    "calculated",
+    "constrained",
+    "provider",
+}
+
+
+def _money(value: str | int | float | Decimal | None) -> Decimal | None:
+    if value in (None, ""):
+        return None
+    return Decimal(str(value))
+
+
+def _tuple_dict(value: dict[str, Any] | None) -> dict[str, Any]:
+    return dict(value or {})
+
+
+@dataclass(frozen=True)
+class ChargeComponent:
+    id: str
+    kind: ChargeComponentKind | str
+    amount: Decimal | None = None
+    cadence: str | None = None
+    meter: str | None = None
+    unit: str | None = None
+    unit_price: Decimal | None = None
+    included_units: Decimal | None = None
+    label: str | None = None
+    billing_treatment: str | None = None
+    metadata: dict[str, Any] = field(default_factory=dict)
+
+
+@dataclass(frozen=True)
+class Commitment:
+    id: str
+    kind: str
+    value: str
+    unit: str | None = None
+    description: str = ""
+
+
+@dataclass(frozen=True)
+class TunableParameter:
+    key: str
+    parameter_class: ParameterClass | str
+    data_type: str
+    description: str = ""
+    default_value: str | None = None
+    min_value: Decimal | None = None
+    max_value: Decimal | None = None
+    options: tuple[str, ...] = ()
+
+
+@dataclass(frozen=True)
+class PricingModel:
+    id: str
+    name: str
+    model_type: str
+    lifecycle_phase: str
+    currency: str
+    access_fee_amount: Decimal
+    access_fee_cadence: str
+    status: PricingModelStatus
+    description: str = ""
+    included_usage: str | None = None
+    overage_meter: str | None = None
+    charge_components: tuple[ChargeComponent, ...] = ()
+    commitments: tuple[Commitment, ...] = ()
+    tunable_parameters: tuple[TunableParameter, ...] = ()
+    eligibility: tuple[str, ...] = ()
+    provider_hints: dict[str, Any] = field(default_factory=dict)
+    metadata: dict[str, Any] = field(default_factory=dict)
+
+
+def _read_json(path: Path) -> dict[str, Any]:
+    return json.loads(path.read_text(encoding="utf-8"))
+
+
+def _parse_charge_component(raw: dict[str, Any]) -> ChargeComponent:
+    return ChargeComponent(
+        id=raw["id"],
+        kind=raw["kind"],
+        amount=_money(raw.get("amount")),
+        cadence=raw.get("cadence"),
+        meter=raw.get("meter"),
+        unit=raw.get("unit"),
+        unit_price=_money(raw.get("unit_price")),
+        included_units=_money(raw.get("included_units")),
+        label=raw.get("label"),
+        billing_treatment=raw.get("billing_treatment"),
+        metadata=_tuple_dict(raw.get("metadata")),
+    )
+
+
+def _parse_commitment(raw: dict[str, Any]) -> Commitment:
+    return Commitment(
+        id=raw["id"],
+        kind=raw["kind"],
+        value=str(raw["value"]),
+        unit=raw.get("unit"),
+        description=raw.get("description", ""),
+    )
+
+
+def _parse_tunable_parameter(raw: dict[str, Any]) -> TunableParameter:
+    return TunableParameter(
+        key=raw["key"],
+        parameter_class=raw["parameter_class"],
+        data_type=raw["data_type"],
+        description=raw.get("description", ""),
+        default_value=str(raw["default_value"]) if raw.get("default_value") is not None else None,
+        min_value=_money(raw.get("min_value")),
+        max_value=_money(raw.get("max_value")),
+        options=tuple(str(item) for item in raw.get("options", [])),
+    )
+
+
+def _legacy_charge_components(raw: dict[str, Any]) -> list[dict[str, Any]]:
+    components: list[dict[str, Any]] = [
+        {
+            "id": f"{raw['id']}-access",
+            "kind": "access",
+            "amount": raw["access_fee_amount"],
+            "cadence": raw["access_fee_cadence"],
+            "label": "Recurring access fee",
+            "billing_treatment": "recurring",
+            "metadata": {"included_usage": raw.get("included_usage")},
+        }
+    ]
+    if raw.get("model_type") == "hybrid_subscription_usage" or raw.get("overage_meter"):
+        components.append(
+            {
+                "id": f"{raw['id']}-usage",
+                "kind": "usage",
+                "meter": raw.get("overage_meter") or "usage",
+                "unit": raw.get("unit") or "usage_unit",
+                "included_units": raw.get("included_units") or raw.get("included_tokens"),
+                "unit_price": raw.get("unit_price") or raw.get("overage_unit_price"),
+                "label": "Variable usage component",
+                "billing_treatment": "metered",
+                "metadata": {"included_usage": raw.get("included_usage")},
+            }
+        )
+    return components
+
+
+def _access_component(components: tuple[ChargeComponent, ...]) -> ChargeComponent | None:
+    return next((component for component in components if component.kind == "access"), None)
+
+
+def _usage_component(components: tuple[ChargeComponent, ...]) -> ChargeComponent | None:
+    return next((component for component in components if component.kind == "usage"), None)
+
+
+def _parse_pricing_model(raw: dict[str, Any]) -> PricingModel:
+    charge_components = tuple(
+        _parse_charge_component(item)
+        for item in (raw.get("charge_components") or _legacy_charge_components(raw))
+    )
+    access_component = _access_component(charge_components)
+    usage_component = _usage_component(charge_components)
+
+    access_fee_amount = _money(raw.get("access_fee_amount"))
+    if access_fee_amount is None:
+        access_fee_amount = access_component.amount if access_component else Decimal("0")
+
+    access_fee_cadence = raw.get("access_fee_cadence")
+    if access_fee_cadence is None:
+        access_fee_cadence = access_component.cadence if access_component else "monthly"
+
+    metadata = _tuple_dict(raw.get("metadata"))
+    included_usage = raw.get("included_usage") or metadata.get("included_usage")
+    if included_usage is None and access_component:
+        included_usage = access_component.metadata.get("included_usage")
+    if included_usage is None and usage_component:
+        included_usage = usage_component.metadata.get("included_usage")
+
+    overage_meter = raw.get("overage_meter") or (usage_component.meter if usage_component else None)
+
+    return PricingModel(
+        id=raw["id"],
+        name=raw["name"],
+        model_type=raw["model_type"],
+        lifecycle_phase=raw["lifecycle_phase"],
+        currency=raw["currency"],
+        access_fee_amount=access_fee_amount or Decimal("0"),
+        access_fee_cadence=access_fee_cadence or "monthly",
+        status=raw["status"],
+        description=raw.get("description", ""),
+        included_usage=included_usage,
+        overage_meter=overage_meter,
+        charge_components=charge_components,
+        commitments=tuple(
+            _parse_commitment(item) for item in raw.get("commitments", [])
+        ),
+        tunable_parameters=tuple(
+            _parse_tunable_parameter(item) for item in raw.get("tunable_parameters", [])
+        ),
+        eligibility=tuple(str(item) for item in raw.get("eligibility", [])),
+        provider_hints=_tuple_dict(raw.get("provider_hints")),
+        metadata=metadata,
+    )
+
+
+def load_pricing_models(path: str | Path) -> list[PricingModel]:
+    raw = _read_json(Path(path))
+    models = [_parse_pricing_model(item) for item in raw["models"]]
+    issues = validate_pricing_catalog(models)
+    if issues:
+        formatted = "; ".join(
+            f"{model_id}: {', '.join(model_issues)}"
+            for model_id, model_issues in sorted(issues.items())
+        )
+        raise ValueError(f"invalid pricing catalog: {formatted}")
+    return models
+
+
+def validate_pricing_catalog(models: list[PricingModel]) -> dict[str, list[str]]:
+    issues: dict[str, list[str]] = {}
+    ids = [model.id for model in models]
+    if len(ids) != len(set(ids)):
+        issues.setdefault("__catalog__", []).append("duplicate model ids")
+    for model in models:
+        model_issues = validate_pricing_model(model)
+        if model_issues:
+            issues[model.id] = model_issues
+    return issues
+
+
+def validate_pricing_model(model: PricingModel) -> list[str]:
+    issues: list[str] = []
+
+    if model.status not in {"active", "candidate", "retired"}:
+        issues.append(f"unsupported status '{model.status}'")
+
+    if model.access_fee_amount < Decimal("0"):
+        issues.append("access_fee_amount must be non-negative")
+
+    if not model.charge_components:
+        issues.append("at least one charge component is required")
+
+    component_ids = [component.id for component in model.charge_components]
+    if len(component_ids) != len(set(component_ids)):
+        issues.append("charge component ids must be unique")
+
+    access_components = [component for component in model.charge_components if component.kind == "access"]
+    if len(access_components) != 1:
+        issues.append("exactly one access charge component is required")
+
+    for component in model.charge_components:
+        if component.kind not in _ALLOWED_COMPONENT_KINDS:
+            issues.append(f"unsupported charge component kind '{component.kind}'")
+        if component.kind == "access":
+            if component.amount is None:
+                issues.append("access charge component must define amount")
+            if component.cadence is None:
+                issues.append("access charge component must define cadence")
+        if component.kind == "usage" and component.meter is None:
+            issues.append("usage charge component must define meter")
+
+    usage_components = [component for component in model.charge_components if component.kind == "usage"]
+    if model.model_type == "hybrid_subscription_usage" and not usage_components:
+        issues.append("hybrid_subscription_usage requires a usage charge component")
+
+    tunable_keys = [parameter.key for parameter in model.tunable_parameters]
+    if len(tunable_keys) != len(set(tunable_keys)):
+        issues.append("tunable parameter keys must be unique")
+
+    for parameter in model.tunable_parameters:
+        if parameter.parameter_class not in _ALLOWED_PARAMETER_CLASSES:
+            issues.append(f"unsupported parameter_class '{parameter.parameter_class}'")
+        if (
+            parameter.parameter_class == "customer_tunable"
+            and not parameter.options
+            and parameter.min_value is None
+            and parameter.max_value is None
+        ):
+            issues.append(
+                f"customer_tunable parameter '{parameter.key}' must define bounds or options"
+            )
+
+    commitment_ids = [commitment.id for commitment in model.commitments]
+    if len(commitment_ids) != len(set(commitment_ids)):
+        issues.append("commitment ids must be unique")
+
+    return issues
diff --git a/docs/PricingModelSchema.md b/docs/PricingModelSchema.md
new file mode 100644
index 0000000..4916ccd
--- /dev/null
+++ b/docs/PricingModelSchema.md
@@ -0,0 +1,113 @@
+# Pricing Model Schema
+
+Status: draft, implementation-facing.
+
+## Purpose
+
+This document defines the canonical pricing-model schema now used by the
+repository runtime. It is the implementation companion to the conceptual
+vocabulary in `research/PricingOntology.md`.
+
+The schema is designed to:
+
+- preserve compatibility with the Coulomb observatory MVP
+- represent richer pricing structures than a single subscription amount
+- support later validation, solver, and provider-publication milestones
+
+## Model Shape
+
+Each pricing model contains:
+
+- identity and lifecycle metadata
+- normalized recurring access-fee fields for compatibility
+- explicit charge components
+- commitments
+- tunable parameters
+- eligibility and provider hints
+- free-form metadata for deployment-specific details
+
+## Canonical Fields
+
+```yaml
+id: string
+name: string
+model_type: flat_subscription | hybrid_subscription_usage | ...
+lifecycle_phase: exploration | introduction | growth | maturity | saturation | decline
+currency: EUR | USD | ...
+status: active | candidate | retired
+description: string
+
+# Compatibility fields derived from the access component when omitted
+access_fee_amount: decimal
+access_fee_cadence: monthly | annual | one_time | ...
+included_usage: string | null
+overage_meter: string | null
+
+charge_components:
+  - id: string
+    kind: access | setup | usage | support | discount | risk_adjustment
+    amount: decimal | null
+    cadence: string | null
+    meter: string | null
+    unit: string | null
+    unit_price: decimal | null
+    included_units: decimal | null
+    label: string | null
+    billing_treatment: recurring | metered | included | one_time | ...
+    metadata: {}
+
+commitments:
+  - id: string
+    kind: minimum_turnover | contract_duration | prepayment | committed_usage | ...
+    value: string
+    unit: string | null
+    description: string
+
+tunable_parameters:
+  - key: string
+    parameter_class: fixed | seller_controlled | customer_tunable | calculated | constrained | provider
+    data_type: string
+    description: string
+    default_value: string | null
+    min_value: decimal | null
+    max_value: decimal | null
+    options: []
+
+eligibility:
+  - string
+
+provider_hints: {}
+metadata: {}
+```
+
+## Parameter Classes
+
+- `fixed`: immutable in the selected model
+- `seller_controlled`: adjustable only by the seller or internal workflow
+- `customer_tunable`: intended to become solver-visible customer choice
+- `calculated`: derived from other fields or economics
+- `constrained`: externally set but bounded by validation rules
+- `provider`: implementation-only parameter for execution backends
+
+## Validation Rules
+
+Current runtime validation enforces:
+
+- model ids are unique
+- charge component ids are unique within a model
+- exactly one `access` charge component exists
+- access components define amount and cadence
+- usage components define a meter
+- `hybrid_subscription_usage` models include a usage charge component
+- tunable parameter keys are unique
+- `customer_tunable` parameters declare bounds or enumerated options
+- commitment ids are unique
+
+## Transitional Compatibility
+
+The Coulomb observatory still consumes `access_fee_amount`, `access_fee_cadence`,
+`included_usage`, and `overage_meter`. The canonical loader back-fills these
+from `charge_components` when the explicit top-level fields are omitted.
+
+This keeps the current observatory stable while later milestones replace
+hard-coded observatory assumptions with generic pricing-core behavior.
diff --git a/projects/coulomb-pricing/data/pricing-models.json b/projects/coulomb-pricing/data/pricing-models.json
index 5292c39..6ce0e70 100644
--- a/projects/coulomb-pricing/data/pricing-models.json
+++ b/projects/coulomb-pricing/data/pricing-models.json
@@ -7,10 +7,45 @@
       "model_type": "flat_subscription",
       "lifecycle_phase": "growth",
       "currency": "EUR",
+      "description": "Current flat membership offer for Coulomb Social.",
       "access_fee_amount": "8.99",
       "access_fee_cadence": "monthly",
       "included_usage": "unlimited_repository_access",
-      "status": "active"
+      "status": "active",
+      "charge_components": [
+        {
+          "id": "membership-access",
+          "kind": "access",
+          "amount": "8.99",
+          "cadence": "monthly",
+          "label": "Standard membership access fee",
+          "billing_treatment": "recurring",
+          "metadata": {
+            "included_usage": "unlimited_repository_access"
+          }
+        }
+      ],
+      "commitments": [
+        {
+          "id": "baseline-term",
+          "kind": "contract_duration",
+          "value": "1",
+          "unit": "month",
+          "description": "Baseline self-serve monthly term."
+        }
+      ],
+      "tunable_parameters": [],
+      "eligibility": [
+        "coulomb-social-members"
+      ],
+      "provider_hints": {
+        "stripe": {
+          "collection_method": "charge_automatically"
+        }
+      },
+      "metadata": {
+        "catalog_version": "canonical-v1"
+      }
     },
     {
       "id": "membership-plus-credits",
@@ -18,10 +53,71 @@
       "model_type": "hybrid_subscription_usage",
       "lifecycle_phase": "exploration",
       "currency": "EUR",
+      "description": "Candidate model bundling recurring access with a monthly AI allowance.",
       "access_fee_amount": "8.99",
       "access_fee_cadence": "monthly",
       "included_usage": "monthly_ai_credit_allowance",
-      "status": "candidate"
+      "status": "candidate",
+      "charge_components": [
+        {
+          "id": "membership-access",
+          "kind": "access",
+          "amount": "8.99",
+          "cadence": "monthly",
+          "label": "Membership base fee",
+          "billing_treatment": "recurring"
+        },
+        {
+          "id": "ai-credit-allowance",
+          "kind": "usage",
+          "meter": "openrouter_tokens",
+          "unit": "tokens",
+          "included_units": "100000",
+          "label": "Included monthly AI token allowance",
+          "billing_treatment": "included",
+          "metadata": {
+            "included_usage": "monthly_ai_credit_allowance"
+          }
+        }
+      ],
+      "commitments": [
+        {
+          "id": "credit-prepay-window",
+          "kind": "prepayment",
+          "value": "1",
+          "unit": "month",
+          "description": "Allowance resets monthly in the observatory prototype."
+        }
+      ],
+      "tunable_parameters": [
+        {
+          "key": "included_tokens",
+          "parameter_class": "seller_controlled",
+          "data_type": "integer",
+          "description": "Included OpenRouter token allowance for the monthly bundle.",
+          "default_value": "100000",
+          "min_value": "50000",
+          "max_value": "500000"
+        },
+        {
+          "key": "monthly_allowance_eur",
+          "parameter_class": "calculated",
+          "data_type": "decimal",
+          "description": "Observatory-only euro allowance derived from provider usage cost.",
+          "default_value": "2.00"
+        }
+      ],
+      "eligibility": [
+        "coulomb-social-members"
+      ],
+      "provider_hints": {
+        "stripe": {
+          "metered_usage_strategy": "future_adapter"
+        }
+      },
+      "metadata": {
+        "catalog_version": "canonical-v1"
+      }
     },
     {
       "id": "membership-plus-overage",
@@ -29,11 +125,82 @@
       "model_type": "hybrid_subscription_usage",
       "lifecycle_phase": "exploration",
       "currency": "EUR",
+      "description": "Candidate model pairing recurring access with included tokens and metered overage.",
       "access_fee_amount": "8.99",
       "access_fee_cadence": "monthly",
       "included_usage": "monthly_ai_credit_allowance",
       "overage_meter": "openrouter_tokens",
-      "status": "candidate"
+      "status": "candidate",
+      "charge_components": [
+        {
+          "id": "membership-access",
+          "kind": "access",
+          "amount": "8.99",
+          "cadence": "monthly",
+          "label": "Membership base fee",
+          "billing_treatment": "recurring"
+        },
+        {
+          "id": "ai-overage-usage",
+          "kind": "usage",
+          "meter": "openrouter_tokens",
+          "unit": "tokens",
+          "included_units": "100000",
+          "unit_price": "0.002",
+          "label": "OpenRouter token overage",
+          "billing_treatment": "metered",
+          "metadata": {
+            "included_usage": "monthly_ai_credit_allowance"
+          }
+        }
+      ],
+      "commitments": [
+        {
+          "id": "baseline-term",
+          "kind": "contract_duration",
+          "value": "1",
+          "unit": "month",
+          "description": "Baseline monthly term; solver can later trade this against usage economics."
+        }
+      ],
+      "tunable_parameters": [
+        {
+          "key": "included_tokens",
+          "parameter_class": "customer_tunable",
+          "data_type": "integer",
+          "description": "Customer-selectable included token allowance within seller-approved bounds.",
+          "default_value": "100000",
+          "min_value": "50000",
+          "max_value": "300000"
+        },
+        {
+          "key": "contract_duration_months",
+          "parameter_class": "customer_tunable",
+          "data_type": "integer",
+          "description": "Longer term can support improved usage pricing in later solver milestones.",
+          "default_value": "1",
+          "min_value": "1",
+          "max_value": "12"
+        },
+        {
+          "key": "overage_unit_price",
+          "parameter_class": "calculated",
+          "data_type": "decimal",
+          "description": "Current observatory overage rate derived from scenario assumptions.",
+          "default_value": "0.002"
+        }
+      ],
+      "eligibility": [
+        "coulomb-social-members"
+      ],
+      "provider_hints": {
+        "stripe": {
+          "meter_name": "openrouter_tokens"
+        }
+      },
+      "metadata": {
+        "catalog_version": "canonical-v1"
+      }
     }
   ]
-}
\ No newline at end of file
+}
diff --git a/projects/coulomb-pricing/observatory/_repo_root.py b/projects/coulomb-pricing/observatory/_repo_root.py
new file mode 100644
index 0000000..a0cbf78
--- /dev/null
+++ b/projects/coulomb-pricing/observatory/_repo_root.py
@@ -0,0 +1,12 @@
+from __future__ import annotations
+
+import sys
+from pathlib import Path
+
+REPO_ROOT = Path(__file__).resolve().parents[3]
+
+
+def ensure_repo_root_on_syspath() -> None:
+    root = str(REPO_ROOT)
+    if root not in sys.path:
+        sys.path.insert(0, root)
diff --git a/projects/coulomb-pricing/observatory/load.py b/projects/coulomb-pricing/observatory/load.py
index b8ec970..bc97e66 100644
--- a/projects/coulomb-pricing/observatory/load.py
+++ b/projects/coulomb-pricing/observatory/load.py
@@ -4,6 +4,10 @@ import json
 from decimal import Decimal
 from pathlib import Path
 
+from ._repo_root import ensure_repo_root_on_syspath
+ensure_repo_root_on_syspath()
+
+from adaptive_pricing_core.pricing_models import load_pricing_models as load_canonical_pricing_models
 from .ledger import build_monthly_ledger
 from .models import (
     Budget,
@@ -50,20 +54,7 @@ def load_budget(data_dir: Path | None = None) -> Budget:
 
 
 def load_pricing_models(data_dir: Path | None = None) -> list[PricingModel]:
-    raw = _read_json((data_dir or default_data_dir()) / "pricing-models.json")
-    return [
-        PricingModel(
-            id=item["id"],
-            name=item["name"],
-            model_type=item["model_type"],
-            lifecycle_phase=item["lifecycle_phase"],
-            currency=item["currency"],
-            access_fee_amount=_money(item["access_fee_amount"]),
-            access_fee_cadence=item["access_fee_cadence"],
-            status=item["status"],
-        )
-        for item in raw["models"]
-    ]
+    return load_canonical_pricing_models((data_dir or default_data_dir()) / "pricing-models.json")
 
 
 def load_fx_rates(data_dir: Path | None = None) -> dict[str, Decimal]:
@@ -150,4 +141,4 @@ def load_monthly_ledger(data_dir: Path | None = None) -> list[MonthlyPlatformCos
 
 
 def latest_period(monthly_costs: list[MonthlyPlatformCost]) -> str:
-    return max(item.period for item in monthly_costs)
\ No newline at end of file
+    return max(item.period for item in monthly_costs)
diff --git a/projects/coulomb-pricing/observatory/models.py b/projects/coulomb-pricing/observatory/models.py
index b966d74..46a8c26 100644
--- a/projects/coulomb-pricing/observatory/models.py
+++ b/projects/coulomb-pricing/observatory/models.py
@@ -4,9 +4,20 @@ from dataclasses import dataclass
 from decimal import Decimal
 from typing import Literal
 
+from ._repo_root import ensure_repo_root_on_syspath
+
+ensure_repo_root_on_syspath()
+
+from adaptive_pricing_core.pricing_models import (  # noqa: E402
+    ChargeComponent,
+    Commitment,
+    PricingModel,
+    PricingModelStatus,
+    TunableParameter,
+)
+
 ExpenseClass = Literal["infrastructure", "payment_processing"]
 MemberStatus = Literal["active", "churned", "paused"]
-PricingModelStatus = Literal["active", "candidate", "retired"]
 LiquidityStatus = Literal["burning", "neutral", "generating"]
 
 
@@ -20,18 +31,6 @@ class Product:
     active_pricing_model_id: str
 
 
-@dataclass(frozen=True)
-class PricingModel:
-    id: str
-    name: str
-    model_type: str
-    lifecycle_phase: str
-    currency: str
-    access_fee_amount: Decimal
-    access_fee_cadence: str
-    status: PricingModelStatus
-
-
 @dataclass(frozen=True)
 class ExpenseRecord:
     id: str
@@ -118,4 +117,4 @@ class LiquiditySummary:
     cumulative_net_liquidity: Decimal
     remaining_budget: Decimal
     liquidity_status: LiquidityStatus
-    months_tracked: int
\ No newline at end of file
+    months_tracked: int
diff --git a/projects/coulomb-pricing/tests/conftest.py b/projects/coulomb-pricing/tests/conftest.py
index e6ac727..aaebfc4 100644
--- a/projects/coulomb-pricing/tests/conftest.py
+++ b/projects/coulomb-pricing/tests/conftest.py
@@ -3,4 +3,8 @@ from pathlib import Path
 
 ROOT = Path(__file__).resolve().parent.parent
 if str(ROOT) not in sys.path:
-    sys.path.insert(0, str(ROOT))
\ No newline at end of file
+    sys.path.insert(0, str(ROOT))
+
+REPO_ROOT = ROOT.parent.parent
+if str(REPO_ROOT) not in sys.path:
+    sys.path.insert(0, str(REPO_ROOT))
diff --git a/projects/coulomb-pricing/tests/test_pricing_model_schema.py b/projects/coulomb-pricing/tests/test_pricing_model_schema.py
new file mode 100644
index 0000000..f499590
--- /dev/null
+++ b/projects/coulomb-pricing/tests/test_pricing_model_schema.py
@@ -0,0 +1,35 @@
+from __future__ import annotations
+
+from decimal import Decimal
+from pathlib import Path
+
+from adaptive_pricing_core.pricing_models import validate_pricing_catalog
+from observatory.load import load_pricing_models
+
+DATA_DIR = Path(__file__).resolve().parent.parent / "data"
+
+
+def test_coulomb_pricing_catalog_validates() -> None:
+    models = load_pricing_models(DATA_DIR)
+    assert validate_pricing_catalog(models) == {}
+
+
+def test_hybrid_model_preserves_usage_component_and_tuning_metadata() -> None:
+    models = load_pricing_models(DATA_DIR)
+    model = next(item for item in models if item.id == "membership-plus-overage")
+
+    usage_component = next(component for component in model.charge_components if component.kind == "usage")
+
+    assert usage_component.meter == "openrouter_tokens"
+    assert usage_component.included_units == Decimal("100000")
+    assert usage_component.unit_price == Decimal("0.002")
+    assert any(parameter.parameter_class == "customer_tunable" for parameter in model.tunable_parameters)
+
+
+def test_flat_model_still_exposes_access_fee_compatibility_fields() -> None:
+    models = load_pricing_models(DATA_DIR)
+    model = next(item for item in models if item.id == "flat-899-eur-monthly")
+
+    assert model.access_fee_amount == Decimal("8.99")
+    assert model.access_fee_cadence == "monthly"
+    assert len(model.charge_components) == 1
diff --git a/workplans/ADAPTIVE-WP-0003-canonical-pricing-core-and-schema.md b/workplans/ADAPTIVE-WP-0003-canonical-pricing-core-and-schema.md
index ba882cb..a565f61 100644
--- a/workplans/ADAPTIVE-WP-0003-canonical-pricing-core-and-schema.md
+++ b/workplans/ADAPTIVE-WP-0003-canonical-pricing-core-and-schema.md
@@ -4,7 +4,7 @@ type: workplan
 title: "Canonical pricing core and schema extraction"
 domain: financials
 repo: adaptive-pricing
-status: ready
+status: finished
 owner: codex
 topic_slug: helix-forge
 created: "2026-07-02"
@@ -21,7 +21,7 @@ define the canonical pricing-model schema needed by the later milestones.
 
 ```task
 id: ADAPTIVE-WP-0003-T01
-status: todo
+status: done
 priority: high
 state_hub_task_id: "c79647e3-f760-4a2f-ae45-a3532692a3d3"
 ```
@@ -34,7 +34,7 @@ eligibility, lifecycle metadata, and provider-mapping hooks.
 
 ```task
 id: ADAPTIVE-WP-0003-T02
-status: todo
+status: done
 priority: high
 state_hub_task_id: "2d27616b-ea0c-4600-b7a2-eb5a22932b58"
 ```
@@ -48,7 +48,7 @@ first adopter of the extracted core rather than leaving the core trapped inside
 
 ```task
 id: ADAPTIVE-WP-0003-T03
-status: todo
+status: done
 priority: high
 state_hub_task_id: "6fa1ee8f-27ae-45b3-bd98-ea2a4873c0c8"
 ```
@@ -61,7 +61,7 @@ commitment-backed models.
 
 ```task
 id: ADAPTIVE-WP-0003-T04
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "fed8cb44-4219-4b7f-b641-90d872ebc285"
 ```
@@ -74,7 +74,7 @@ existing dashboard behavior.
 
 ```task
 id: ADAPTIVE-WP-0003-T05
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "77305962-6f56-44aa-a8e4-32cfc5de262b"
 ```
@@ -83,4 +83,3 @@ Exit when the repo has a documented canonical schema, a validator with tests,
 and a working Coulomb observatory instance backed by the new internal model.
 
 Dependencies: `ADAPTIVE-WP-0002` completed baseline.
-