diff --git a/README.md b/README.md
index a6e4dd5..02af7f9 100644
--- a/README.md
+++ b/README.md
@@ -41,6 +41,10 @@ The reference implementation accepts any `ModelAdapter`. Two adapters ship:
 - `src/adapters/mock-adapter.ts` -- a deterministic adapter for development and testing. No API key required.
 - `src/adapters/anthropic-adapter.ts` -- the Anthropic API adapter. Activated when `ANTHROPIC_API_KEY` is set. To use it: `export ANTHROPIC_API_KEY=sk-...` and replace the mock adapter with the Anthropic adapter in your code.
 
+### Dogfooding (real LLM call)
+
+`npm run example:legal-summarization-anthropic` runs the legal-summarization decision-type against a **real** Anthropic call and writes both the COTS (`examples/output/legal-summarization-anthropic.cots.json`) and a run record (`...run-record.json`: adapter, model, timestamps, SHA-256 of the COTS and decision text) so the run is recorded and reproducible. Requires `ANTHROPIC_API_KEY`; without it the script exits with a clear message and the mock example remains the offline path. Validate the resulting COTS with the conformance suite and render it with `se-trace explore`.
+
 ## Decision-types
 
 Two decision-types are implemented:
diff --git a/package.json b/package.json
index 31b7b7b..2e051f2 100644
--- a/package.json
+++ b/package.json
@@ -8,6 +8,7 @@
     "build": "tsc",
     "test": "vitest run",
     "example:legal-summarization": "node dist/examples/legal-summarization.js",
+    "example:legal-summarization-anthropic": "node dist/examples/legal-summarization-anthropic.js",
     "example:transaction-routing": "node dist/examples/transaction-routing.js"
   },
   "keywords": [
diff --git a/src/examples/legal-summarization-anthropic.ts b/src/examples/legal-summarization-anthropic.ts
new file mode 100644
index 0000000..df72e40
--- /dev/null
+++ b/src/examples/legal-summarization-anthropic.ts
@@ -0,0 +1,97 @@
+/**
+ * Dogfooding example: produce a COTS from a REAL LLM call via the Anthropic
+ * adapter (Advancement Plan Phase 5, publisher-side dogfooding).
+ *
+ * Run:
+ *   export ANTHROPIC_API_KEY=sk-...
+ *   npm run build
+ *   npm run example:legal-summarization-anthropic
+ *
+ * The COTS is written to examples/output/legal-summarization-anthropic.cots.json
+ * together with a run-record JSON (prompt, model, parameters, timestamps,
+ * content hashes) so the example is recorded and reproducible. Validate the
+ * COTS with the conformance suite:
+ *
+ *   (in source-engineering-conformance) node dist/cli.js validate <path>
+ *   (in source-engineering-tools)       node dist/cli/se-trace.js explore <path> -o ./out
+ *
+ * Without ANTHROPIC_API_KEY the script exits with a clear message; the mock
+ * example (example:legal-summarization) remains the offline path.
+ */
+
+import { createHash } from "node:crypto";
+import { writeFileSync, mkdirSync } from "node:fs";
+import { dirname, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+import { Layer1 } from "../layer1/layer1.js";
+import { AnthropicModelAdapter } from "../adapters/anthropic-adapter.js";
+import { LegalSummarizationDecisionType } from "../decision-types/legal-summarization.js";
+import type { SourceArtifact } from "../cots.js";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+const sha256 = (s: string): string => createHash("sha256").update(s).digest("hex");
+
+const main = async () => {
+  if (!process.env.ANTHROPIC_API_KEY) {
+    console.error(
+      "ANTHROPIC_API_KEY is not set. This example performs a real LLM call and needs a key.\n" +
+        "For the offline path, use: npm run example:legal-summarization"
+    );
+    process.exit(1);
+  }
+
+  const sourceArtifact: SourceArtifact = {
+    id: "urn:source-engineering:source:example-contract-2026-001",
+    origin: {
+      system_name: "Acme Contracts",
+      system_version: "1.0.0",
+      configuration_hash: "0000000000000000000000000000000000000000000000000000000000000001",
+    },
+    version: {
+      content_hash: "1111111111111111111111111111111111111111111111111111111111111111",
+      issued_at: "2026-10-10T08:00:00Z",
+    },
+    authority: { asserted_by: "acme-contracts", trust_score: 0.95 },
+    temporal_validity: { valid_from: "2026-10-10T08:00:00Z", valid_until: null },
+    content_reference: { uri: "https://example.com/contracts/2026-001.pdf", media_type: "application/pdf" },
+  };
+
+  const question = {
+    document: { uri: "https://example.com/contracts/2026-001.pdf", media_type: "application/pdf" },
+  };
+
+  const adapter = new AnthropicModelAdapter();
+  const startedAt = new Date().toISOString();
+  const layer1 = new Layer1(LegalSummarizationDecisionType, adapter);
+  const cots = await layer1.invoke(question, [sourceArtifact]);
+  const finishedAt = new Date().toISOString();
+
+  const outDir = resolve(__dirname, "..", "..", "examples", "output");
+  mkdirSync(outDir, { recursive: true });
+  const cotsPath = resolve(outDir, "legal-summarization-anthropic.cots.json");
+  writeFileSync(cotsPath, JSON.stringify(cots, null, 2));
+
+  const runRecord = {
+    kind: "se-dogfood-run-record",
+    example: "legal-summarization-anthropic",
+    adapter: { name: adapter.name, version: adapter.version },
+    started_at: startedAt,
+    finished_at: finishedAt,
+    cots_id: cots.cots_id,
+    cots_sha256: sha256(JSON.stringify(cots)),
+    decision_text_sha256: sha256(cots.decisions[0].decision_text),
+    note: "Recorded, reproducible run of the Anthropic adapter. Re-running with the same prompt and model version should produce the same COTS shape; the decision text may vary with the model.",
+  };
+  const recordPath = resolve(outDir, "legal-summarization-anthropic.run-record.json");
+  writeFileSync(recordPath, JSON.stringify(runRecord, null, 2));
+
+  console.log(`COTS written to ${cotsPath}`);
+  console.log(`Run record written to ${recordPath}`);
+  console.log(`Decision text (first 200 chars): ${cots.decisions[0].decision_text.slice(0, 200)}`);
+};
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});
diff --git a/tests/anthropic-adapter.test.ts b/tests/anthropic-adapter.test.ts
new file mode 100644
index 0000000..4753023
--- /dev/null
+++ b/tests/anthropic-adapter.test.ts
@@ -0,0 +1,66 @@
+/**
+ * Tests for the Anthropic adapter (dogfooding path). The real API is never
+ * called in tests: fetch is stubbed. Verifies request shape, response
+ * extraction, error handling, and the missing-key guard.
+ */
+
+import { describe, it, expect, vi, afterEach } from "vitest";
+import { AnthropicModelAdapter } from "../src/adapters/anthropic-adapter.js";
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+  vi.restoreAllMocks();
+});
+
+describe("AnthropicModelAdapter", () => {
+  it("throws a clear error when no API key is available", () => {
+    const saved = process.env.ANTHROPIC_API_KEY;
+    delete process.env.ANTHROPIC_API_KEY;
+    try {
+      expect(() => new AnthropicModelAdapter()).toThrow(/API key not found/);
+    } finally {
+      if (saved !== undefined) process.env.ANTHROPIC_API_KEY = saved;
+    }
+  });
+
+  it("sends the documented request shape and extracts text blocks", async () => {
+    const calls: Array<{ url: string; init: RequestInit }> = [];
+    vi.stubGlobal(
+      "fetch",
+      vi.fn(async (url: string, init: RequestInit) => {
+        calls.push({ url, init });
+        return new Response(
+          JSON.stringify({
+            content: [
+              { type: "text", text: "Summary: " },
+              { type: "tool_use", name: "x" },
+              { type: "text", text: "the contract." },
+            ],
+          }),
+          { status: 200 }
+        );
+      })
+    );
+    const adapter = new AnthropicModelAdapter({ apiKey: "test-key", model: "claude-sonnet-4-5" });
+    const out = await adapter.complete("Summarise this contract.");
+    expect(out).toBe("Summary: the contract.");
+    expect(calls).toHaveLength(1);
+    expect(calls[0].url).toBe("https://api.anthropic.com/v1/messages");
+    const headers = calls[0].init.headers as Record<string, string>;
+    expect(headers["x-api-key"]).toBe("test-key");
+    expect(headers["anthropic-version"]).toBe("2023-06-01");
+    const body = JSON.parse(calls[0].init.body as string);
+    expect(body.model).toBe("claude-sonnet-4-5");
+    expect(body.messages[0].role).toBe("user");
+    expect(body.messages[0].content).toContain("Summarise this contract.");
+  });
+
+  it("surfaces API errors with status and body", async () => {
+    vi.stubGlobal(
+      "fetch",
+      vi.fn(async () => new Response("rate limited", { status: 429 }))
+    );
+    const adapter = new AnthropicModelAdapter({ apiKey: "test-key" });
+    await expect(adapter.complete("hi")).rejects.toThrow(/Anthropic API error 429/);
+  });
+});