diff --git a/src/server.test.ts b/src/server.test.ts
index ed51df3..006d716 100644
--- a/src/server.test.ts
+++ b/src/server.test.ts
@@ -3,6 +3,9 @@ import { after, describe, it } from "node:test";
 
 import { buildApp } from "./server.js";
 import { setServers } from "node:dns";
+import { allowedNodeEnvironmentFlags } from "node:process";
+import { unescape } from "node:querystring";
+import { error } from "node:console";
 
 describe("API endpoints", () => {
   const app = buildApp();
@@ -212,4 +215,85 @@ describe("API endpoints", () => {
     });
     assert.equal(response.body.includes("Sensitive internal detail"), false);
   });
+
+  it("POST /documents ingests a valid document", async () => {
+    const app = buildApp(undefined, undefined, async (document) => {
+      assert.equal(document.title, "Test document");
+      assert.equal(document.source, "unit-test");
+      assert.equal(document.content, "Document content.");
+      return { documentId: "42", chunkCount: 1 };
+    });
+
+    try {
+      const response = await app.inject({
+        method: "POST",
+        url: "/documents",
+        payload: {
+          title: "Test document",
+          source: "unit-test",
+          content: "Document content.",
+        },
+      });
+
+      assert.equal(response.statusCode, 201);
+      assert.deepEqual(response.json(), {
+        documentId: "42",
+        chunkCount: 1,
+      });
+    } finally {
+      await app.close();
+    }
+  });
+
+  it("POST / documents rejects invalid input", async () => {
+    const app = buildApp(undefined, undefined, async () => {
+      throw new Error("Ingestions should not run");
+    });
+
+    try {
+      const response = await app.inject({
+        method: "POST",
+        url: "/documents",
+        payload: {
+          title: "   ",
+          content: "Document content.",
+        },
+      });
+
+      assert.equal(response.statusCode, 400);
+      assert.deepEqual(response.json(), {
+        error: "Invalid document",
+      });
+    } finally {
+      await app.close();
+    }
+  });
+
+  it("POST /documents returns 503 when ingestion fails", async () => {
+    const app = buildApp(undefined, undefined, async () => {
+      throw new Error("Database connection details");
+    });
+
+    try {
+      const response = await app.inject({
+        method: "POST",
+        url: "/documents",
+        payload: {
+          title: "Test document",
+          content: "Document content.",
+        },
+      });
+
+      assert.equal(response.statusCode, 503);
+      assert.deepEqual(response.json(), {
+        error: "Document ingestion failed",
+      });
+      assert.equal(
+        response.body.includes("Database connection details"),
+        false,
+      );
+    } finally {
+      await app.close();
+    }
+  });
 });
diff --git a/src/server.ts b/src/server.ts
index 07b96c1..8c473d7 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -1,7 +1,7 @@
 import Fastify, { type FastifyError } from "fastify";
 import { z } from "zod";
 
-import { ingestDocument } from "./ingestion.js";
+import { ingestDocument as ingestDocumentDefault } from "./ingestion.js";
 import { checkOllamaHealth, generateResponse } from "./ollama.js";
 
 const echoSchema = z.object({
@@ -10,13 +10,14 @@ const echoSchema = z.object({
 
 const documentSchema = z.object({
   title: z.string().trim().min(1).max(200),
-  source: z.string().trim().max(2_00).optional(),
+  source: z.string().trim().max(2_000).optional(),
   content: z.string().trim().min(1).max(100_000),
 });
 
 export const buildApp = (
   generate = generateResponse,
   checkHealth = checkOllamaHealth,
+  ingest = ingestDocumentDefault,
 ) => {
   const app = Fastify({
     logger: true,
@@ -112,7 +113,7 @@ export const buildApp = (
     }
 
     try {
-      const document = await ingestDocument(result.data);
+      const document = await ingest(result.data);
 
       return reply.code(201).send(document);
     } catch (error) {