diff --git a/etc/eslint/rules/stdlib.js b/etc/eslint/rules/stdlib.js
index a55ab53096ef..f8a35c60aba8 100644
--- a/etc/eslint/rules/stdlib.js
+++ b/etc/eslint/rules/stdlib.js
@@ -4157,6 +4157,25 @@ rules[ 'stdlib/no-dynamic-require' ] = 'error';
*/
rules[ 'stdlib/no-empty-comments' ] = 'error';
+/**
+* Disallow string concatenation in error messages.
+*
+* @name no-error-string-concat
+* @memberof rules
+* @type {string}
+* @default 'error'
+*
+* @example
+* // Bad...
+* throw new Error( 'invalid argument. Value: `' + value + '`.' );
+*
+* @example
+* // Good...
+* throw new Error( 'unexpected error.' );
+* throw new Error( format( 'invalid argument. Value: `%s`.', value ) );
+*/
+rules[ 'stdlib/no-error-string-concat' ] = 'error';
+
/**
* Enforce that `require()` expressions are not immediately invoked.
*
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
index 817b943efba0..0560718171bd 100644
--- a/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/lib/index.js
@@ -882,6 +882,15 @@ setReadOnly( rules, 'no-dynamic-require', require( '@stdlib/_tools/eslint/rules/
*/
setReadOnly( rules, 'no-empty-comments', require( '@stdlib/_tools/eslint/rules/no-empty-comments' ) );
+/**
+* @name no-error-string-concat
+* @memberof rules
+* @readonly
+* @type {Function}
+* @see {@link module:@stdlib/_tools/eslint/rules/no-error-string-concat}
+*/
+setReadOnly( rules, 'no-error-string-concat', require( '@stdlib/_tools/eslint/rules/no-error-string-concat' ) );
+
/**
* @name no-immediate-require
* @memberof rules
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/README.md b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/README.md
new file mode 100644
index 000000000000..fcf8555bb5ec
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/README.md
@@ -0,0 +1,120 @@
+
+
+# no-error-string-concat
+
+> [ESLint rule][eslint-rules] disallowing string concatenation in error messages.
+
+
+
+
+
+
+
+## Usage
+
+```javascript
+var rule = require( '@stdlib/_tools/eslint/rules/no-error-string-concat' );
+```
+
+#### rule
+
+[ESLint rule][eslint-rules] disallowing string concatenation in error messages.
+
+**Bad**:
+
+
+
+
+
+```javascript
+throw new Error( 'invalid argument. Value: `' + value + '`.' );
+```
+
+**Good**:
+
+
+
+```javascript
+var format = require( '@stdlib/string/format' );
+
+throw new Error( format( 'invalid argument. Value: `%s`.', value ) );
+```
+
+
+
+
+
+
+
+## Examples
+
+```javascript
+var Linter = require( 'eslint' ).Linter;
+var rule = require( '@stdlib/_tools/eslint/rules/no-error-string-concat' );
+
+var linter = new Linter();
+linter.defineRule( 'no-error-string-concat', rule );
+
+var code = 'throw new Error( \'invalid argument. Value: `\' + value + \'`.\' );';
+var result = linter.verify( code, {
+ 'rules': {
+ 'no-error-string-concat': 'error'
+ }
+});
+/* returns
+ [
+ {
+ 'ruleId': 'no-error-string-concat',
+ 'severity': 2,
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'line': 1,
+ 'column': 18,
+ 'nodeType': 'BinaryExpression',
+ 'endLine': 1,
+ 'endColumn': 61
+ }
+ ]
+*/
+```
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+[eslint-rules]: https://eslint.org/docs/developer-guide/working-with-rules
+
+
+
+
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/examples/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/examples/index.js
new file mode 100644
index 000000000000..e82f7a5c13c4
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/examples/index.js
@@ -0,0 +1,47 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var Linter = require( 'eslint' ).Linter;
+var rule = require( './../lib' );
+
+var linter = new Linter();
+linter.defineRule( 'no-error-string-concat', rule );
+
+var code = 'throw new Error( \'invalid argument. Value: `\' + value + \'`.\' );';
+var result = linter.verify( code, {
+ 'rules': {
+ 'no-error-string-concat': 'error'
+ }
+});
+console.log( result );
+/* =>
+ [
+ {
+ 'ruleId': 'no-error-string-concat',
+ 'severity': 2,
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'line': 1,
+ 'column': 18,
+ 'nodeType': 'BinaryExpression',
+ 'endLine': 1,
+ 'endColumn': 61
+ }
+ ]
+*/
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/index.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/index.js
new file mode 100644
index 000000000000..52587016940d
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/index.js
@@ -0,0 +1,39 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* ESLint rule disallowing string concatenation in error messages.
+*
+* @module @stdlib/_tools/eslint/rules/no-error-string-concat
+*
+* @example
+* var rule = require( '@stdlib/_tools/eslint/rules/no-error-string-concat' );
+*
+* console.log( rule );
+*/
+
+// MODULES //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/main.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/main.js
new file mode 100644
index 000000000000..00e544a04ee4
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/lib/main.js
@@ -0,0 +1,145 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// VARIABLES //
+
+var ERROR_CONSTRUCTORS = [
+ 'Error',
+ 'TypeError',
+ 'RangeError',
+ 'SyntaxError',
+ 'ReferenceError',
+ 'URIError',
+ 'EvalError'
+];
+var rule;
+
+
+// FUNCTIONS //
+
+/**
+* Checks whether a node is a BinaryExpression using the addition operator.
+*
+* @private
+* @param {ASTNode} node - AST node
+* @returns {boolean} boolean indicating whether the node is a binary addition expression
+*/
+function isBinaryAddition( node ) {
+ return node.type === 'BinaryExpression' && node.operator === '+';
+}
+
+/**
+* Checks whether a callee name is an error constructor.
+*
+* @private
+* @param {string} name - callee name
+* @returns {boolean} boolean indicating whether the name is an error constructor
+*/
+function isErrorConstructor( name ) {
+ var i;
+ for ( i = 0; i < ERROR_CONSTRUCTORS.length; i++ ) {
+ if ( name === ERROR_CONSTRUCTORS[ i ] ) {
+ return true;
+ }
+ }
+ return false;
+}
+
+/**
+* Rule for validating that `@stdlib/string/format` is used instead of string concatenation in error messages.
+*
+* @param {Object} context - ESLint context
+* @returns {Object} validators
+*/
+function main( context ) {
+ /**
+ * Reports the error message.
+ *
+ * @private
+ * @param {ASTNode} node - node to report
+ */
+ function report( node ) {
+ context.report({
+ 'node': node,
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.'
+ });
+ }
+
+ /**
+ * Checks whether an error constructor call uses string concatenation in its first argument.
+ *
+ * @private
+ * @param {ASTNode} node - CallExpression or NewExpression node to examine
+ */
+ function validate( node ) {
+ var firstArg;
+ var callee;
+ var name;
+
+ callee = node.callee;
+
+ // Get the constructor name:
+ if ( callee.type === 'Identifier' ) {
+ name = callee.name;
+ } else {
+ return;
+ }
+
+ // Check if this is a call to an error constructor:
+ if ( !isErrorConstructor( name ) ) {
+ return;
+ }
+
+ // Check if there is at least one argument:
+ if ( node.arguments.length === 0 ) {
+ return;
+ }
+
+ firstArg = node.arguments[ 0 ];
+
+ // Check if the first argument uses the addition operator:
+ if ( isBinaryAddition( firstArg ) ) {
+ report( firstArg );
+ }
+ }
+
+ return {
+ 'NewExpression': validate,
+ 'CallExpression': validate
+ };
+}
+
+
+// MAIN //
+
+rule = {
+ 'meta': {
+ 'docs': {
+ 'description': 'disallow string concatenation in error messages'
+ },
+ 'schema': []
+ },
+ 'create': main
+};
+
+
+// EXPORTS //
+
+module.exports = rule;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/package.json b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/package.json
new file mode 100644
index 000000000000..b012505ef738
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/package.json
@@ -0,0 +1,53 @@
+{
+ "name": "@stdlib/_tools/eslint/rules/no-error-string-concat",
+ "version": "0.0.0",
+ "description": "ESLint rule disallowing string concatenation in error messages.",
+ "license": "Apache-2.0",
+ "author": {
+ "name": "The Stdlib Authors",
+ "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+ },
+ "contributors": [
+ {
+ "name": "The Stdlib Authors",
+ "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+ }
+ ],
+ "bin": {},
+ "main": "./lib",
+ "directories": {
+ "example": "./examples",
+ "lib": "./lib",
+ "test": "./test"
+ },
+ "scripts": {},
+ "homepage": "https://github.com/stdlib-js/stdlib",
+ "repository": {
+ "type": "git",
+ "url": "git://github.com/stdlib-js/stdlib.git"
+ },
+ "bugs": {
+ "url": "https://github.com/stdlib-js/stdlib/issues"
+ },
+ "dependencies": {},
+ "devDependencies": {},
+ "engines": {
+ "node": ">=0.10.0",
+ "npm": ">2.7.0"
+ },
+ "keywords": [
+ "stdlib",
+ "tools",
+ "tool",
+ "eslint",
+ "lint",
+ "custom",
+ "rules",
+ "rule",
+ "plugin",
+ "error",
+ "string",
+ "concatenation",
+ "format"
+ ]
+}
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/invalid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/invalid.js
new file mode 100644
index 000000000000..dde04596f9b2
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/invalid.js
@@ -0,0 +1,122 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var invalid = [];
+
+// Simple string concatenation in Error:
+var test = {
+ 'code': 'throw new Error( \'invalid argument. Value: `\' + value + \'`.\' );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in TypeError:
+test = {
+ 'code': 'throw new TypeError( \'expected a string. Value: `\' + x + \'`.\' );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in RangeError:
+test = {
+ 'code': 'throw new RangeError( idx + \' is out of bounds.\' );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// Error called without new:
+test = {
+ 'code': 'throw Error( \'invalid argument. Value: `\' + value + \'`.\' );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in SyntaxError:
+test = {
+ 'code': 'throw new SyntaxError( \'unexpected token: \' + token );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in ReferenceError:
+test = {
+ 'code': 'throw new ReferenceError( name + \' is not defined.\' );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in URIError:
+test = {
+ 'code': 'throw new URIError( \'invalid URI: \' + uri );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+// String concatenation in EvalError:
+test = {
+ 'code': 'throw new EvalError( \'eval error: \' + msg );',
+ 'errors': [
+ {
+ 'message': 'Use `@stdlib/string/format` instead of string concatenation in error messages.',
+ 'type': 'BinaryExpression'
+ }
+ ]
+};
+invalid.push( test );
+
+
+// EXPORTS //
+
+module.exports = invalid;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/unvalidated.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/unvalidated.js
new file mode 100644
index 000000000000..739356344ba9
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/unvalidated.js
@@ -0,0 +1,56 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var valid = [];
+
+// String concatenation in non-error constructor:
+var test = {
+ 'code': 'new MyClass( \'prefix\' + value );'
+};
+valid.push( test );
+
+// String concatenation in regular function call:
+test = {
+ 'code': 'console.log( \'value: \' + x );'
+};
+valid.push( test );
+
+// String concatenation assigned to variable, then used in error:
+test = {
+ 'code': 'var msg = \'invalid: \' + x;\nthrow new Error( msg );'
+};
+valid.push( test );
+
+// Member expression (not a simple identifier):
+test = {
+ 'code': 'throw new errors.CustomError( \'prefix\' + value );'
+};
+valid.push( test );
+
+// String concatenation in second argument:
+test = {
+ 'code': 'throw new Error( \'message\', \'cause: \' + x );'
+};
+valid.push( test );
+
+
+// EXPORTS //
+
+module.exports = valid;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/valid.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/valid.js
new file mode 100644
index 000000000000..79aaefed8125
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/fixtures/valid.js
@@ -0,0 +1,62 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var valid = [];
+
+// Using a string literal:
+var test = {
+ 'code': 'throw new Error( \'unexpected error.\' );'
+};
+valid.push( test );
+
+// Using format function:
+test = {
+ 'code': 'throw new Error( format( \'invalid argument. First argument must be a number. Value: `%s`.\', value ) );'
+};
+valid.push( test );
+
+// Using a variable:
+test = {
+ 'code': 'var msg = \'error message\';\nthrow new Error( msg );'
+};
+valid.push( test );
+
+// Error constructor without arguments:
+test = {
+ 'code': 'throw new Error();'
+};
+valid.push( test );
+
+// TypeError with string literal:
+test = {
+ 'code': 'throw new TypeError( \'expected a string.\' );'
+};
+valid.push( test );
+
+// RangeError with format:
+test = {
+ 'code': 'throw new RangeError( format( \'index out of bounds. Value: `%d`.\', idx ) );'
+};
+valid.push( test );
+
+
+// EXPORTS //
+
+module.exports = valid;
diff --git a/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/test.js b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/test.js
new file mode 100644
index 000000000000..c204a6820904
--- /dev/null
+++ b/lib/node_modules/@stdlib/_tools/eslint/rules/no-error-string-concat/test/test.js
@@ -0,0 +1,86 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var RuleTester = require( 'eslint' ).RuleTester;
+var rule = require( './../lib' );
+
+
+// FIXTURES //
+
+var valid = require( './fixtures/valid.js' );
+var invalid = require( './fixtures/invalid.js' );
+var unvalidated = require( './fixtures/unvalidated.js' );
+
+
+// TESTS //
+
+tape( 'main export is an object', function test( t ) {
+ t.ok( true, __filename );
+ t.strictEqual( typeof rule, 'object', 'main export is an object' );
+ t.end();
+});
+
+tape( 'the rule positively validates code using `format` instead of string concatenation in error messages', function test( t ) {
+ var tester = new RuleTester();
+
+ try {
+ tester.run( 'no-error-string-concat', rule, {
+ 'valid': valid,
+ 'invalid': []
+ });
+ t.pass( 'passed without errors' );
+ } catch ( err ) {
+ t.fail( 'encountered an error: ' + err.message );
+ }
+ t.end();
+});
+
+tape( 'the rule negatively validates code using string concatenation instead of `format` in error messages', function test( t ) {
+ var tester = new RuleTester();
+
+ try {
+ tester.run( 'no-error-string-concat', rule, {
+ 'valid': [],
+ 'invalid': invalid
+ });
+ t.pass( 'passed without errors' );
+ } catch ( err ) {
+ t.fail( 'encountered an error: ' + err.message );
+ }
+ t.end();
+});
+
+tape( 'the rule does not validate string concatenation outside of error constructors', function test( t ) {
+ var tester = new RuleTester();
+
+ try {
+ tester.run( 'no-error-string-concat', rule, {
+ 'valid': unvalidated,
+ 'invalid': []
+ });
+ t.pass( 'passed without errors' );
+ } catch ( err ) {
+ t.fail( 'encountered an error: ' + err.message );
+ }
+ t.end();
+});