feat(core-eslint): add no-undeclared-rate-limit conformance rule

Adds the `no-undeclared-rate-limit` ESLint rule (warn severity) that
enforces rate-limit drift at lint time:

- Warns when rateLimit.consume("X", _) is called inside a use-case but
  "X" is absent from manifest.useCases[name].rateLimit
- Warns when a declared rateLimit budget has no matching consume call
  in the use-case body (unusedDeclaration)
- Is a no-op outside use-case files

Extends _manifest-ast.js to extract the rateLimit[] field from both
parseManifestUseCases and parseManifestFully. Updates _manifest-ast
tests to include the new field in expected shapes. Registers the rule
at warn severity in plugin.js and base.js. Adds RuleTester fixtures
for all four cases (declared+matching, undeclared, unused, non-use-case).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

coverage/summary.json

@@ -1,6 +1,6 @@
 {
-  "generatedAt": "2026-05-20T08:30:19.042Z",
+  "generatedAt": "2026-05-20T08:43:15.868Z",
-  "commit": "e2a5278",
+  "commit": "a478a8e",
   "repo": {
     "statements": 97.41,
     "branches": 92.31,

packages/core-eslint/base.js

@@ -54,6 +54,7 @@ export default [
       "conformance/atomic-tier-import-direction": "warn",
       "conformance/pii-declaration-must-be-complete": "warn",
       "conformance/no-undeclared-consent-check": ["warn", { repoRoot }],
+      "conformance/no-undeclared-rate-limit": ["warn", { repoRoot }],
     },
   },
   {

packages/core-eslint/plugin.js

@@ -10,6 +10,7 @@ import componentMustHaveTest from "./rules/component-must-have-test.js";
 import atomicTierImportDirection from "./rules/atomic-tier-import-direction.js";
 import piiDeclarationMustBeComplete from "./rules/pii-declaration-must-be-complete.js";
 import noUndeclaredConsentCheck from "./rules/no-undeclared-consent-check.js";
+import noUndeclaredRateLimit from "./rules/no-undeclared-rate-limit.js";
 
 /**
  * The `@repo/core-eslint` conformance plugin. Aggregates custom rules that
@@ -39,6 +40,7 @@ const plugin = {
     "atomic-tier-import-direction": atomicTierImportDirection,
     "pii-declaration-must-be-complete": piiDeclarationMustBeComplete,
     "no-undeclared-consent-check": noUndeclaredConsentCheck,
+    "no-undeclared-rate-limit": noUndeclaredRateLimit,
   },
 };
 

packages/core-eslint/rules/_manifest-ast.js

@@ -87,6 +87,7 @@ function extractUseCaseEntry(objExpr) {
     publishes: [],
     consumes: [],
     analyticsEvents: [],
+    rateLimit: [],
   };
   for (const prop of objExpr.properties) {
     if (prop.type !== "Property" || prop.key.type !== "Identifier") continue;
@@ -97,7 +98,8 @@ function extractUseCaseEntry(objExpr) {
       (key === "audits" ||
         key === "publishes" ||
         key === "consumes" ||
-        key === "analyticsEvents") &&
+        key === "analyticsEvents" ||
+        key === "rateLimit") &&
       prop.value.type === "ArrayExpression"
     ) {
       entry[key] = extractStringLiterals(prop.value);
@@ -219,6 +221,7 @@ function extractUseCaseEntryFromObj(objExpr) {
     publishes: [],
     consumes: [],
     analyticsEvents: [],
+    rateLimit: [],
   };
   for (const prop of objExpr.properties) {
     if (prop.type !== "Property" || prop.key.type !== "Identifier") continue;
@@ -229,7 +232,8 @@ function extractUseCaseEntryFromObj(objExpr) {
       (key === "audits" ||
         key === "publishes" ||
         key === "consumes" ||
-        key === "analyticsEvents") &&
+        key === "analyticsEvents" ||
+        key === "rateLimit") &&
       prop.value.type === "ArrayExpression"
     ) {
       entry[key] = extractStringLiterals(prop.value);

packages/core-eslint/rules/_manifest-ast.test.js

@@ -42,6 +42,7 @@ describe("parseManifestUseCases", () => {
         publishes: [],
         consumes: [],
         analyticsEvents: [],
+        rateLimit: [],
       },
       signUp: {
         mutates: true,
@@ -49,6 +50,7 @@ describe("parseManifestUseCases", () => {
         publishes: ["auth.signed-up"],
         consumes: [],
         analyticsEvents: [],
+        rateLimit: [],
       },
       signOut: {
         mutates: true,
@@ -56,6 +58,7 @@ describe("parseManifestUseCases", () => {
         publishes: [],
         consumes: [],
         analyticsEvents: [],
+        rateLimit: [],
       },
     });
   });
@@ -94,6 +97,7 @@ describe("parseManifestFully", () => {
           publishes: [],
           consumes: [],
           analyticsEvents: [],
+          rateLimit: [],
         },
         signUp: {
           mutates: true,
@@ -101,6 +105,7 @@ describe("parseManifestFully", () => {
           publishes: [],
           consumes: [],
           analyticsEvents: [],
+          rateLimit: [],
         },
       },
     });

packages/core-eslint/rules/no-undeclared-rate-limit.js

@@ -0,0 +1,67 @@
+import { parseManifestUseCases } from "./_manifest-ast.js";
+import { manifestPathForFeature } from "./_manifest-source.js";
+import { repoRootSchema } from "./_rule-schema.js";
+import { resolveRuleContext } from "./_rule-context.js";
+
+/** @type {import("eslint").Rule.RuleModule} */
+export default {
+  meta: {
+    type: "suggestion",
+    docs: {
+      description:
+        'rateLimit.consume("X", _) inside a use-case file must match a budget declared in manifest.useCases[name].rateLimit.',
+    },
+    schema: repoRootSchema,
+    messages: {
+      undeclared:
+        '{{useCase}} calls rateLimit.consume("{{budget}}") but "{{budget}}" is not declared in manifest.useCases.{{useCase}}.rateLimit. Add it to the manifest or remove the call.',
+      unusedDeclaration:
+        '{{useCase}} declares rateLimit budget "{{budget}}" in the manifest but rateLimit.consume("{{budget}}") is never called in this file. Add the consume call or remove the manifest declaration.',
+    },
+  },
+  create(context) {
+    const rc = resolveRuleContext(context);
+    if (!rc) return {};
+    const { useCaseName, featureRoot } = rc;
+    const manifest = parseManifestUseCases(manifestPathForFeature(featureRoot));
+    if (!manifest || !manifest[useCaseName]) return {};
+    const declared = new Set(manifest[useCaseName].rateLimit ?? []);
+    const consumed = new Set();
+
+    return {
+      CallExpression(node) {
+        if (
+          node.callee.type === "MemberExpression" &&
+          node.callee.object.type === "Identifier" &&
+          node.callee.object.name === "rateLimit" &&
+          node.callee.property.type === "Identifier" &&
+          node.callee.property.name === "consume" &&
+          node.arguments.length > 0 &&
+          node.arguments[0].type === "Literal" &&
+          typeof node.arguments[0].value === "string"
+        ) {
+          const budget = node.arguments[0].value;
+          consumed.add(budget);
+          if (!declared.has(budget)) {
+            context.report({
+              node,
+              messageId: "undeclared",
+              data: { budget, useCase: useCaseName },
+            });
+          }
+        }
+      },
+      "Program:exit"(node) {
+        for (const budget of declared) {
+          if (!consumed.has(budget)) {
+            context.report({
+              node,
+              messageId: "unusedDeclaration",
+              data: { budget, useCase: useCaseName },
+            });
+          }
+        }
+      },
+    };
+  },
+};

packages/core-eslint/rules/no-undeclared-rate-limit.test.js

@@ -0,0 +1,143 @@
+import { describe, it } from "vitest";
+import { RuleTester } from "eslint";
+import path from "node:path";
+import os from "node:os";
+import fs from "node:fs";
+import rule from "./no-undeclared-rate-limit.js";
+
+function makeFixture({ manifestRateLimit, useCaseBody }) {
+  const repoRoot = fs.mkdtempSync(path.join(os.tmpdir(), "nurl-"));
+  const featureDir = path.join(repoRoot, "packages", "demo");
+  fs.mkdirSync(path.join(featureDir, "src", "application", "use-cases"), {
+    recursive: true,
+  });
+  const rateLimitField =
+    manifestRateLimit.length > 0
+      ? `, rateLimit: [${manifestRateLimit.map((b) => `"${b}"`).join(", ")}]`
+      : "";
+  fs.writeFileSync(
+    path.join(featureDir, "src", "feature.manifest.ts"),
+    `export const demoManifest = defineFeature({
+  name: "demo",
+  requiredCores: [],
+  useCases: {
+    signUp: { mutates: true, audits: [], publishes: [], consumes: []${rateLimitField} },
+  },
+  realtimeChannels: [],
+  jobs: [],
+} as const);`,
+  );
+  const useCaseFile = path.join(
+    featureDir,
+    "src",
+    "application",
+    "use-cases",
+    "sign-up.use-case.ts",
+  );
+  fs.writeFileSync(useCaseFile, useCaseBody);
+  return { repoRoot, useCaseFile };
+}
+
+const tester = new RuleTester({
+  languageOptions: {
+    parser: await import("@typescript-eslint/parser"),
+    ecmaVersion: "latest",
+    sourceType: "module",
+  },
+});
+
+describe("no-undeclared-rate-limit", () => {
+  it("passes when rateLimit.consume budget matches manifest rateLimit[]", () => {
+    const { repoRoot, useCaseFile } = makeFixture({
+      manifestRateLimit: ["signUp.ip"],
+      useCaseBody: `export const signUpUseCase = (rateLimit) => async (input) => { await rateLimit.consume("signUp.ip", input.ip); };`,
+    });
+    tester.run("no-undeclared-rate-limit", rule, {
+      valid: [
+        {
+          filename: useCaseFile,
+          code: fs.readFileSync(useCaseFile, "utf8"),
+          options: [{ repoRoot }],
+        },
+      ],
+      invalid: [],
+    });
+  });
+
+  it("fires when rateLimit.consume budget is not declared in manifest", () => {
+    const { repoRoot, useCaseFile } = makeFixture({
+      manifestRateLimit: [],
+      useCaseBody: `export const signUpUseCase = (rateLimit) => async (input) => { await rateLimit.consume("signUp.ip", input.ip); };`,
+    });
+    tester.run("no-undeclared-rate-limit", rule, {
+      valid: [],
+      invalid: [
+        {
+          filename: useCaseFile,
+          code: fs.readFileSync(useCaseFile, "utf8"),
+          options: [{ repoRoot }],
+          errors: [
+            {
+              messageId: "undeclared",
+              data: { budget: "signUp.ip", useCase: "signUp" },
+            },
+          ],
+        },
+      ],
+    });
+  });
+
+  it("fires when a declared budget is never consumed in the use-case body", () => {
+    const { repoRoot, useCaseFile } = makeFixture({
+      manifestRateLimit: ["signUp.ip"],
+      useCaseBody: `export const signUpUseCase = () => async () => { return { ok: true }; };`,
+    });
+    tester.run("no-undeclared-rate-limit", rule, {
+      valid: [],
+      invalid: [
+        {
+          filename: useCaseFile,
+          code: fs.readFileSync(useCaseFile, "utf8"),
+          options: [{ repoRoot }],
+          errors: [
+            {
+              messageId: "unusedDeclaration",
+              data: { budget: "signUp.ip", useCase: "signUp" },
+            },
+          ],
+        },
+      ],
+    });
+  });
+
+  it("is a no-op for non-use-case files", () => {
+    const { repoRoot } = makeFixture({
+      manifestRateLimit: ["signUp.ip"],
+      useCaseBody: `export const signUpUseCase = (rateLimit) => async (input) => { await rateLimit.consume("signUp.ip", input.ip); };`,
+    });
+    const serviceFile = path.join(
+      repoRoot,
+      "packages",
+      "demo",
+      "src",
+      "application",
+      "services",
+      "sign-up.service.ts",
+    );
+    fs.mkdirSync(path.dirname(serviceFile), { recursive: true });
+    fs.writeFileSync(
+      serviceFile,
+      `export function doWork(rateLimit) { rateLimit.consume("undeclared", "x"); }`,
+    );
+    tester.run("no-undeclared-rate-limit", rule, {
+      valid: [
+        {
+          filename: serviceFile,
+          code: fs.readFileSync(serviceFile, "utf8"),
+          options: [{ repoRoot }],
+        },
+      ],
+      invalid: [],
+    });
+  });
+});