// 03 — everything in 01+02, plus modular inheritance: `extends` + `patches`.
// (structure/capabilities trimmed here — see 01/02.) Standalone models have extends=null and no patches.
{
  "schema_version": "architecture-template-v0",
  "model_type": "mistral",

  // ▼▼▼ the tier-03 addition ▼▼▼
  "extends": "llama",           // dominant parent model_type (from modular_mistral.py)
  "patches": [                  // per-class changes vs the parent; trivial (unchanged) classes are omitted
    { "relation": "inherits", "target_class": "MistralAttention", "component_kind": "attention",
      "parent_class": "LlamaAttention", "overridden": { "methods": ["__init__", "forward"] } },
    { "relation": "inherits", "target_class": "MistralMLP", "component_kind": "feed_forward",
      "parent_class": "LlamaMLP", "overridden": { "methods": ["__init__"] } },
    { "relation": "new", "target_class": "MistralForQuestionAnswering", "component_kind": null,
      "parent_class": "MistralPreTrainedModel" }
    // … relation: "inherits" | "new"; buckets: overridden / added / deleted, each { methods?, attrs? }
  ],
  // ▲▲▲ the diff_size metric is NOT here — it lives per-node in modular_graph.json (see bottom) ▲▲▲

  "architecture": { "view": "decoder", "family": "causal_lm", "attention_variant": "GQA", "positional": "rope" },
  "capabilities": { "attention_backends": ["eager", "sdpa", "flash_attention", "flex_attention"],
                    "kernels": { "RMSNorm": ["kernels-community/rmsnorm"] } },
  "config": {
    "class_name": "MistralConfig", "module": "transformers.models.mistral.configuration_mistral", "model_type": "mistral",
    "referenced_fields": { "num_hidden_layers": 32 }
  },
  "components": [
    { "id": "model", "kind": "model", "class_name": "MistralModel", "path_pattern": "model",
      "children": ["embed_tokens", "decoder_layers", "norm"] }
    // … see 01
  ],
  "templates": [
    { "id": "decoder_layer.self_attn", "kind": "attention", "class_name": "MistralAttention",
      "path_pattern": "model.layers.{i}.self_attn", "attributes": { "variant": "GQA", "pattern": "sliding" } }
    // … see 01
  ],
  "repeats": [
    { "id": "decoder_layers", "kind": "symbolic_repeat", "body": "decoder_layer",
      "count_expr": "config.num_hidden_layers", "count": 32, "count_source": "config", "index_symbol": "i",
      "container_path_pattern": "model.layers", "item_path_pattern": "model.layers.{i}",
      "repeated_class_name": "MistralDecoderLayer" }
  ],
  "edges": [ { "source": "embed_tokens", "target": "decoder_layers", "kind": "data" } ],
  "dataflow": {
    "source": "observed_forward_meta",
    "input": { "name": "input_ids", "shape": ["B", "S"] },
    "output": { "shape": ["B", "S", "config.hidden_size"] },
    "shapes": { "embed_tokens": { "in": ["B", "S"], "out": ["B", "S", "config.hidden_size"] } }
  },
  "provenance": {
    "config_class": "MistralConfig", "config_module": "transformers.models.mistral.configuration_mistral",
    "model_class": "MistralModel", "model_module": "transformers.models.mistral.modeling_mistral"
  }
}

// Companion library-wide file `modular_graph.json` (one for the whole library, not per model):
//   { "schema_version": "modular-graph-v0",
//     "roots": ["llama", "vit", "clip"],
//     "nodes": { "mistral": { "extends": "llama", "children": ["mixtral"], "root": "llama",
//                             "depth": 1, "is_modular": true, "diff_size": 9 } } }
// → models sharing a `root` are the same lineage (align cleanly for comparison); diff_size = modularity metric.