diff --git a/CHANGELOG.md b/CHANGELOG.md
index e0436b1..db5e9dc 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Source string artifact fields support bounded exact `one_of` options for
+  classification labels, with a physical CSV/JSON material-intake example.
+  Unknown labels fail without value disclosure; classifications do not prove approval.
 - Source `https_url` artifact fields validate bounded HTTPS addresses
   against exact declared DNS hosts, with an offline knowledge-source inventory.
   The checker never fetches sources, retains URL values in reports or proves truth.
diff --git a/README.md b/README.md
index e1e4934..a56211a 100644
--- a/README.md
+++ b/README.md
@@ -34,11 +34,13 @@ The command above verifies the included sample Skill. Replace the fixture path w
 
 ## What you get
 
-- The local source candidate `artifacts` command independently checks actual
+- The source `artifacts` command independently checks actual
   CSV/JSON delivery files, Receipt/file hashes and cross-file count/integer sums.
   See [actual artifact checks](docs/artifact-delivery.md); it runs no Skill code.
   The [knowledge source inventory](fixtures/product/source-index/README.md) adds
   exact declared HTTPS hosts to physical CSV/JSON checks without fetching sources.
+  The [material intake catalog](fixtures/product/review-intake/README.md) rejects
+  unknown classification labels using bounded `one_of` strings; labels do not prove approval.
 - `verify` reviews one local Skill for provenance, target compatibility, and changes without running its scripts.
 - `scan` inventories local Skills, while `compat` checks their declared features against agent profiles.
 - `diff` shows the meaningful changes between two Skill versions before you accept them.
diff --git a/docs/artifact-delivery.md b/docs/artifact-delivery.md
index b29ee32..53998ce 100644
--- a/docs/artifact-delivery.md
+++ b/docs/artifact-delivery.md
@@ -48,6 +48,21 @@ follow redirects, assess the source text or prove that a named host is public or
 trustworthy. Exact URL spelling remains unchanged for uniqueness comparisons.
 Optional JSON fields may be omitted; an empty URL does not represent a source.
 
+String fields can declare `one_of` with 1–32 unique exact options, each limited
+to 256 UTF-16 code units. Options cannot contain surrounding whitespace, control
+or format characters. Other scalar types cannot carry `one_of`; an `equals`
+value must also be in the declared list. An empty option requires
+`allow_empty: true`. Matching does not trim, normalize, fold case or coerce types;
+CSV formula rejection still applies. Optional JSON fields may still be omitted.
+
+For example, `{ "name": "currency", "type": "string", "one_of": ["CNY", "USD"] }`
+checks only that the label is one of the caller's declarations. The
+[material intake catalog](../fixtures/product/review-intake/README.md) demonstrates
+domain and decision labels in physical CSV/JSON plus independent reference totals.
+These classifications do not authenticate reviewers, authorize actions or prove
+business correctness. This source extension is not in npm0.1.0; findings omit
+the actual string values.
+
 `bytes` rules check integrity and capacity without interpreting content. JSON
 checks cover declared top-level fields, not full JSON Schema or arbitrary
 expressions. Contract files are limited to 64 KiB. Limits must be explicit and
diff --git a/docs/domain-adaptation.md b/docs/domain-adaptation.md
index 1f5a6d3..89e955b 100644
--- a/docs/domain-adaptation.md
+++ b/docs/domain-adaptation.md
@@ -47,6 +47,10 @@ not vendor certification, and unknown/runtime-dependent features stay explicit.
   checks actual bounded CSV/JSON, exact HTTPS host declarations and independent
   reference counts. It is not in npm0.1.0 and does not verify external source truth.
 - Add further versioned input-schema checks and bounded fixture resources.
+- The source [material intake catalog](../fixtures/product/review-intake/README.md)
+  checks caller-declared domain/decision labels in real CSV/JSON with bounded
+  `one_of` string options. Labels are exact data classifications, not authenticated
+  approval or semantic review; this source extension is not in npm0.1.0.
 - Add references and output-evidence requirements for additional domains.
 - Validate a separately approved local execution backend using synthetic inputs
   before describing it as an actual integration.
diff --git a/fixtures/product/review-intake/README.md b/fixtures/product/review-intake/README.md
new file mode 100644
index 0000000..4ae7fe1
--- /dev/null
+++ b/fixtures/product/review-intake/README.md
@@ -0,0 +1,30 @@
+# Bounded material intake labels
+
+This synthetic source example checks actual CSV and JSON using closed string
+options. It demonstrates a shared intake format for code-review material,
+knowledge references and operations data; it performs no semantic review,
+approval, authenticated handoff or external platform connection.
+
+```bash
+npm run build
+node dist/cli/index.js artifacts \
+  --contract fixtures/product/review-intake/contract.json \
+  --path fixtures/product/review-intake/artifacts --format json
+```
+
+Three synthetic records have exact declared domains and decision labels. The
+summary independently matches their row count and three reference markers. An
+unknown or mistyped label fails even when numeric summaries still match. A
+permitted label such as `ready` does not prove a person reviewed or approved the
+material; the labels are only declared data values. Reference markers do not
+prove source truth.
+
+The contract allows two files, 16 KiB per file, 32 KiB total and 1,000 CSV rows.
+`one_of` accepts 1–32 unique literal strings of at most 256 UTF-16 code units,
+with no surrounding whitespace, control or format characters. Matching is exact:
+no trimming, case folding, regular-expression evaluation or type coercion. An
+empty option requires `allow_empty: true`. Values are not included in findings.
+
+These checks use the current source implementation. They are not in the public
+npm0.1.0 package, and are physical-file evidence with execution `not-run` and
+provenance `not-authenticated`.
diff --git a/fixtures/product/review-intake/artifacts/materials.csv b/fixtures/product/review-intake/artifacts/materials.csv
new file mode 100644
index 0000000..848a64e
--- /dev/null
+++ b/fixtures/product/review-intake/artifacts/materials.csv
@@ -0,0 +1,4 @@
+material_id,domain,decision,reference_count
+SYN-MAT-001,code-review,needs-review,1
+SYN-MAT-002,knowledge-reference,ready,2
+SYN-MAT-003,data-ops,blocked,0
diff --git a/fixtures/product/review-intake/artifacts/summary.json b/fixtures/product/review-intake/artifacts/summary.json
new file mode 100644
index 0000000..d65b16b
--- /dev/null
+++ b/fixtures/product/review-intake/artifacts/summary.json
@@ -0,0 +1,6 @@
+{
+  "schema_version": 1,
+  "row_count": 3,
+  "total_references": 3,
+  "queue": "manual-review"
+}
diff --git a/fixtures/product/review-intake/contract.json b/fixtures/product/review-intake/contract.json
new file mode 100644
index 0000000..926d352
--- /dev/null
+++ b/fixtures/product/review-intake/contract.json
@@ -0,0 +1,31 @@
+{
+  "schema": "skillsync.artifacts/v1",
+  "limits": { "max_files": 2, "max_file_bytes": 16384, "max_total_bytes": 32768 },
+  "files": [
+    {
+      "path": "materials.csv",
+      "format": "csv",
+      "columns": [
+        { "name": "material_id", "type": "string" },
+        { "name": "domain", "type": "string", "one_of": ["code-review", "knowledge-reference", "data-ops"] },
+        { "name": "decision", "type": "string", "one_of": ["ready", "needs-review", "blocked"] },
+        { "name": "reference_count", "type": "integer", "min": 0, "max": 10 }
+      ],
+      "min_rows": 1,
+      "max_rows": 1000,
+      "unique_by": ["material_id"]
+    },
+    {
+      "path": "summary.json",
+      "format": "json",
+      "fields": [
+        { "name": "schema_version", "type": "integer", "equals": 1 },
+        { "name": "row_count", "type": "integer", "min": 1, "max": 1000 },
+        { "name": "total_references", "type": "integer", "min": 0, "max": 10000 },
+        { "name": "queue", "type": "string", "one_of": ["manual-review", "triage"] }
+      ]
+    }
+  ],
+  "checks": [{ "type": "csv_summary", "csv": "materials.csv", "json": "summary.json",
+    "row_count_field": "row_count", "sums": [{ "column": "reference_count", "field": "total_references" }] }]
+}
diff --git a/src/domain/artifact-content.ts b/src/domain/artifact-content.ts
index 6c3d77b..c7ebc0f 100644
--- a/src/domain/artifact-content.ts
+++ b/src/domain/artifact-content.ts
@@ -63,6 +63,8 @@ function scalarValid(value: unknown, rule: ArtifactScalarRule): boolean {
   if (rule.type === "boolean" && typeof value !== "boolean") return false;
   if (rule.type === "array" && !Array.isArray(value)) return false;
   if (rule.type === "object" && (!value || typeof value !== "object" || Array.isArray(value))) return false;
+  // One bounded literal list; do not coerce, normalize, evaluate or retain values.
+  if (rule.one_of !== undefined && (typeof value !== "string" || !rule.one_of.includes(value))) return false;
   if (rule.equals !== undefined && value !== rule.equals) return false;
   if (typeof value === "number" && ((rule.min !== undefined && value < rule.min) || (rule.max !== undefined && value > rule.max))) return false;
   return true;
diff --git a/src/domain/artifact-contract.ts b/src/domain/artifact-contract.ts
index 17f15e4..7cf02c7 100644
--- a/src/domain/artifact-contract.ts
+++ b/src/domain/artifact-contract.ts
@@ -15,6 +15,8 @@ const scalar = z.object({
   name: z.string().min(1).max(128),
   type: z.enum(["string", "integer", "number", "boolean", "date", "https_url", "array", "object"]),
   allowed_hosts: z.array(allowedHost).min(1).max(16).optional(),
+  one_of: z.array(z.string().max(256).refine(value => value === value.trim() &&
+    !/[\p{Cc}\p{Cf}]/u.test(value), "options must be exact plain strings")).min(1).max(32).optional(),
   required: z.boolean().default(true),
   equals: z.union([z.string(), z.number().finite(), z.boolean()]).optional(),
   min: z.number().finite().optional(), max: z.number().finite().optional(),
@@ -56,6 +58,10 @@ export const artifactContractSchema = z.object({ schema: z.literal("skillsync.ar
     const rules = file.format === "csv" ? file.columns : file.format === "json" ? file.fields : [];
     if (new Set(rules.map(rule => rule.name)).size !== rules.length) fail();
     for (const rule of rules) {
+      if (rule.one_of !== undefined && (rule.type !== "string" ||
+        new Set(rule.one_of).size !== rule.one_of.length ||
+        (!rule.allow_empty && rule.one_of.includes("")) ||
+        (rule.equals !== undefined && (typeof rule.equals !== "string" || !rule.one_of.includes(rule.equals))))) fail();
       if (rule.type === "https_url" ? !rule.allowed_hosts ||
         new Set(rule.allowed_hosts).size !== rule.allowed_hosts.length : rule.allowed_hosts !== undefined) fail();
       if ((rule.min !== undefined || rule.max !== undefined) && !["integer", "number"].includes(rule.type)) fail();
diff --git a/tests/domain/artifact-enum-values.test.ts b/tests/domain/artifact-enum-values.test.ts
new file mode 100644
index 0000000..23b0826
--- /dev/null
+++ b/tests/domain/artifact-enum-values.test.ts
@@ -0,0 +1,84 @@
+import { describe, expect, it } from "vitest";
+import { parseArtifactContract } from "../../src/domain/artifact-contract";
+import { inspectArtifactContent } from "../../src/domain/artifact-content";
+
+function contract(field: Record<string, unknown> = {}) {
+  return { schema: "skillsync.artifacts/v1",
+    limits: { max_files: 1, max_file_bytes: 4096, max_total_bytes: 4096 },
+    files: [{ path: "review.json", format: "json", fields: [{
+      name: "decision", type: "string", one_of: ["ready", "needs-review", "blocked"], ...field,
+    }] }] };
+}
+
+function inspect(value: unknown, field: Record<string, unknown> = {}) {
+  return inspectArtifactContent(parseArtifactContract(contract(field)).files[0],
+    Buffer.from(JSON.stringify({ decision: value })));
+}
+
+describe("bounded exact scalar options", () => {
+  it.each(["ready", "needs-review", "blocked"])("accepts declared value %s", value => {
+    expect(inspect(value).findings).toEqual([]);
+  });
+
+  it.each(["approved", "Ready", " ready", "ready ", "re\u200Bady", "", 1, true, null, { label: "ready" }])("rejects unlisted or mistyped material without retaining it: %j", value => {
+      const report = inspect(value);
+      expect(report.findings).toEqual([{ code: "artifact.json-value", path: "review.json", field: "decision" }]);
+      expect(report.facts.integers.size).toBe(0);
+      expect(Object.keys(report.facts)).toEqual(["integers"]);
+    });
+
+  it("shares the same rule with actual CSV cells", () => {
+    const rule = parseArtifactContract({ ...contract(), files: [{ path: "review.csv", format: "csv",
+      columns: [{ name: "decision", type: "string", one_of: ["ready", "blocked"] }], max_rows: 10 }] }).files[0];
+    expect(inspectArtifactContent(rule, Buffer.from("decision\nready\nblocked\n")).findings).toEqual([]);
+    expect(inspectArtifactContent(rule, Buffer.from("decision\nReady\n")).findings)
+      .toContainEqual({ code: "artifact.csv-value", path: "review.csv", field: "decision", row: 1 });
+  });
+
+  it("preserves formula rejection even for an explicitly listed string", () => {
+    const rule = parseArtifactContract({ ...contract(), files: [{ path: "review.csv", format: "csv",
+      columns: [{ name: "decision", type: "string", one_of: ["+ready"] }], max_rows: 10 }] }).files[0];
+    expect(inspectArtifactContent(rule, Buffer.from("decision\n+ready\n")).findings)
+      .toContainEqual({ code: "artifact.csv-formula", path: "review.csv", field: "decision", row: 1 });
+  });
+
+  it("allows an empty option only when the rule explicitly allows empty material", () => {
+    expect(inspect("", { one_of: ["", "ready"], allow_empty: true }).findings).toEqual([]);
+    expect(() => parseArtifactContract(contract({ one_of: ["", "ready"] }))).toThrow("artifact contract is invalid");
+  });
+
+  it("does not require an optional JSON field to be present", () => {
+    const rule = parseArtifactContract(contract({ required: false })).files[0];
+    expect(inspectArtifactContent(rule, Buffer.from("{}")).findings).toEqual([]);
+  });
+
+  it.each([
+    { one_of: [] }, { one_of: ["ready", "ready"] }, { one_of: [1] },
+    { one_of: Array.from({ length: 33 }, (_, index) => `state-${index}`) },
+    { one_of: ["x".repeat(257)] }, { one_of: [" ready"] },
+    { one_of: ["ready\n"] }, { one_of: ["re\u200Bady"] },
+    { type: "integer", one_of: ["1"] }, { type: "date", one_of: ["2026-10-08"] },
+    { type: "https_url", allowed_hosts: ["docs.example.test"], one_of: ["https://docs.example.test/"] },
+    { equals: "approved" },
+  ])("rejects inconsistent or unbounded declarations: %j", field => {
+    expect(() => parseArtifactContract(contract(field))).toThrow("artifact contract is invalid");
+  });
+
+  it("accepts the inclusive 32-option and 256-character boundaries", () => {
+    const values = ["x".repeat(256), ...Array.from({ length: 31 }, (_, index) => `state-${index}`)];
+    expect(inspect(values[0], { one_of: values, equals: values[0] }).findings).toEqual([]);
+  });
+
+  it("keeps original string contracts unchanged when options are absent", () => {
+    const rule = parseArtifactContract(contract({ one_of: undefined })).files[0];
+    expect(JSON.stringify(rule)).not.toContain("one_of");
+    expect(inspectArtifactContent(rule, Buffer.from('{"decision":"any-original-string"}')).findings).toEqual([]);
+  });
+
+  it("uses caller-declared currency labels without interpreting monetary values", () => {
+    expect(inspect("CNY", { one_of: ["CNY", "USD"] }).findings).toEqual([]);
+    expect(inspect("cny", { one_of: ["CNY", "USD"] }).findings)
+      .toContainEqual({ code: "artifact.json-value", path: "review.json", field: "decision" });
+    expect(inspect("待审", { one_of: ["待审", "已完成"] }).findings).toEqual([]);
+  });
+});
diff --git a/tests/integration/review-intake.test.ts b/tests/integration/review-intake.test.ts
new file mode 100644
index 0000000..42bf2f1
--- /dev/null
+++ b/tests/integration/review-intake.test.ts
@@ -0,0 +1,63 @@
+import { cp, mkdtemp, readFile, rm, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join, resolve } from "node:path";
+import { describe, expect, it } from "vitest";
+import { runArtifacts, renderArtifacts } from "../../src/cli/commands/artifacts";
+import { createCli } from "../../src/cli/index";
+
+const source = resolve("fixtures/product/review-intake");
+async function fixture(run: (contract: string, data: string) => Promise<void>) {
+  const root = await mkdtemp(join(tmpdir(), "skillsync-review-intake-"));
+  try {
+    await cp(join(source, "artifacts"), join(root, "artifacts"), { recursive: true });
+    await cp(join(source, "contract.json"), join(root, "contract.json"));
+    await run(join(root, "contract.json"), join(root, "artifacts"));
+  } finally { await rm(root, { recursive: true, force: true }); }
+}
+
+describe("physical review intake labels", () => {
+  it("accepts three synthetic domain records and a matching reference summary", async () => fixture(async (contract, data) => {
+    const report = await runArtifacts({ contract, path: data });
+    expect(report.status).toBe("passed");
+    expect(report.evidence).toBe("physical-files");
+    expect(report.execution).toBe("not-run");
+    expect(report.provenance).toBe("not-authenticated");
+    expect(report.files.find(file => file.path === "materials.csv")?.rows).toBe(3);
+  }));
+
+  it("fails unknown CSV labels through the CLI without exposing values or absolute paths", async () => fixture(async (contract, data) => {
+    const path = join(data, "materials.csv"), value = "PRIVATE_SYNTHETIC_SELECTION";
+    await writeFile(path, (await readFile(path, "utf8")).replace("needs-review", value));
+    const report = await runArtifacts({ contract, path: data });
+    expect(report.findings).toContainEqual({ code: "artifact.csv-value", path: "materials.csv", field: "decision", row: 1 });
+    for (const format of ["json", "text"]) {
+      const output = renderArtifacts(report, format);
+      expect(output).not.toContain(value);
+      expect(output).not.toContain(data);
+    }
+    let output = "", exitCode = 0;
+    const cli = createCli({ writeOut: text => { output += text; }, writeErr: () => undefined, setExitCode: code => { exitCode = code; } });
+    await cli.parseAsync(["node", "skillsync", "artifacts", "--contract", contract, "--path", data, "--format", "json"]);
+    expect(exitCode).toBe(1);
+    expect(JSON.parse(output).status).toBe("failed");
+    expect(output).not.toContain(value);
+  }));
+
+  it("applies the same closed options to the JSON summary", async () => fixture(async (contract, data) => {
+    const path = join(data, "summary.json");
+    const summary = JSON.parse(await readFile(path, "utf8"));
+    summary.queue = "AUTOMATIC_APPROVAL_NOT_DECLARED";
+    await writeFile(path, JSON.stringify(summary));
+    expect((await runArtifacts({ contract, path: data })).findings)
+      .toContainEqual({ code: "artifact.json-value", path: "summary.json", field: "queue" });
+  }));
+
+  it("retains independent aggregate checks when all labels are allowed", async () => fixture(async (contract, data) => {
+    const path = join(data, "summary.json");
+    const summary = JSON.parse(await readFile(path, "utf8"));
+    summary.total_references = 99;
+    await writeFile(path, JSON.stringify(summary));
+    expect((await runArtifacts({ contract, path: data })).findings)
+      .toContainEqual({ code: "artifact.summary-sum", path: "summary.json", field: "total_references" });
+  }));
+});