Test tagging
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Analyzes test suites in any language and tags each test with standardized traits (positive, negative, critical-path, boundary, smoke, regression, integration, performance, security). Use when the user wants to categorize, audit, or label tests with traits. Works across .NET (MSTest/xUnit/NUnit/TUnit), Python (pytest), TS/JS (Jest/Vitest), Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, and C++ — auto-editing when the framework has canonical tag syntax, otherwise report-only. Do not use for writing new tests, running tests, or migrating frameworks.
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SKILL.md
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Test Trait Tagging
Analyze an existing test suite in any supported language and apply a standardized set of trait tags to each test method, giving teams visibility into their test distribution (positive vs. negative, critical-path coverage, smoke tests, etc.).
Language-specific guidance: Call the
test-analysis-extensionsskill to discover available extension files, then read the file matching the target codebase. The extension file documents framework-specific tag attributes and a "tag-support capability" (auto-edit, report-only, or convention-based) that drives whether this skill modifies source files or only emits a report.
When to Use
- Auditing a test project to understand the mix of test types
- Adding trait attributes to untagged tests
- Generating a summary report of trait distribution across a test suite
- Reviewing whether critical paths have sufficient coverage
When Not to Use
- Writing new tests from scratch (use
code-testing-agentfor any language, orwriting-mstest-testsfor MSTest) - Running or filtering tests (use
run-testsfor .NET; equivalent native runners elsewhere) - Migrating between test frameworks
Inputs
| Input | Required | Description |
|---|---|---|
| Test project or files | Yes | Path to the test project, folder, or specific test files to analyze |
| Scope | No | tag (apply attributes when language supports auto-edit), audit (report only), or both (default: both). For languages with no canonical tag syntax, the skill emits a report regardless of scope. |
| Framework | No | Auto-detected. Override when detection fails. |
Trait Taxonomy
Use exactly these trait names and values. Do not invent new trait values outside this table.
| Trait Value | Meaning | Heuristics |
|---|---|---|
positive | Verifies expected behavior under normal/valid conditions | Asserts success, valid output, expected state, no exceptions for valid input |
negative | Verifies correct handling of invalid input, errors, or edge cases | Asserts exceptions, error codes, validation failures, rejects bad input |
boundary | Tests limits, thresholds, empty/null/None/nil inputs, min/max values | Operates on 0, -1, int.MaxValue / sys.maxsize / Number.MAX_SAFE_INTEGER / math.MaxInt64 / i32::MAX, empty string, null/None/nil/undefined, empty collection, boundary of valid range |
critical-path | Core workflow that must never break; breakage blocks users | Tests the primary success scenario of a key public API or user-facing feature |
smoke | Quick sanity check that the system is operational | Fast, no complex setup, verifies basic wiring (e.g., service resolves, endpoint returns 200) |
regression | Reproduces a specific previously-reported bug | References a bug ID, issue number, or describes a fix in its name or comments |
integration | Crosses process, network, or persistence boundaries | Uses real database, HTTP client, file system, external service, or multi-component setup |
end-to-end | Full user workflow spanning the entire application stack | Exercises a complete scenario from entry point to final result, distinct from single-boundary integration |
performance | Validates timing, throughput, or resource consumption | Asserts on elapsed time, memory, allocations, or uses benchmark harness (BenchmarkDotNet, pytest-benchmark, benchmark.js, JMH, go test -bench, criterion.rs, XCTMetric, kotlinx-benchmark, Google Benchmark) |
security | Verifies authentication, authorization, input sanitization, or secrets handling | Tests for SQL injection, XSS, CSRF, unauthorized access, token validation, permission checks |
concurrency | Validates thread safety, parallelism, or async correctness | Uses Task.WhenAll / Parallel.ForEach / SemaphoreSlim (.NET); asyncio.gather / threading.Lock / multiprocessing (Python); Promise.all / worker threads (JS/TS); CompletableFuture / ExecutorService / synchronized (Java); go func / sync.WaitGroup / sync.Mutex / chan (Go); Mutex / Thread.new (Ruby); tokio::spawn / Arc<Mutex<_>> / crossbeam (Rust); DispatchQueue / actor (Swift); coroutineScope / Mutex (Kotlin); Start-Job / RunspacePool (PowerShell); std::thread / std::mutex (C++); reproduces race conditions |
resilience | Tests retry logic, timeouts, circuit breakers, or graceful degradation | Asserts behavior under transient failures, network drops, or service unavailability (e.g., Polly, tenacity, p-retry, resilience4j, hystrix, opossum, retry-go) |
destructive | Mutates shared or external state that is hard to roll back | Deletes records, drops resources, modifies global config -- useful for CI isolation decisions |
configuration | Verifies settings loading, defaults, environment behavior | Tests missing config keys, invalid values, environment variable fallbacks, options validation |
flaky | Known to intermittently fail (meta-tag for test health tracking) | Mark tests the team knows are unreliable; used to quarantine or prioritize stabilization |
A single test may have multiple traits (e.g., both negative and boundary). At minimum, every test should receive one of positive or negative.
Workflow
Step 1: Detect the language, framework, and tagging capability
Identify the codebase's language and test framework. Call the test-analysis-extensions skill and read the matching extension file. The extension file declares a tag-support capability for each framework:
auto-edit— framework has canonical tag syntax this skill can safely insert (.NET[TestCategory]/[Trait]/[Category]/[Property], pytest@pytest.mark.<name>, JUnit 5@Tag("..."), TestNGgroups = {"..."}, RSpec metadatait "..." , :tag => true, Pester-Tag '...', Kotest@Tags(...), Swift Testing@Tag(.tagName), Catch2[tag], doctest* doctest::test_suite("tag")decorator).report-only— framework has no canonical, agreed-upon tag attribute; report tags in a Markdown table only and do not edit source (Go standardtestingwithout build-tag conventions, Jest/Vitest without consistent describe-prefix convention, Rust without project-specific cfg conventions, XCTest without a test plan, GoogleTest without test-name prefix conventions, Mocha without describe-prefix conventions).convention-based— framework uses naming or file conventions for tagging (Go//go:build integrationbuild tags, file-name suffixes like*_integration_test.go, GoogleTestINTEGRATION_*filter prefix). Only emit canonical edits when the user has confirmed the project convention; otherwise treat asreport-only.
Capture the capability before Step 4.
Step 2: Scan existing traits
Check which tests already have trait attributes. Use the loaded language extension as the source of truth — examples:
| Framework | Existing Attribute | Example |
|---|---|---|
| MSTest | [TestCategory("...")] | [TestCategory("positive")] |
| xUnit | [Trait("Category", "...")] | [Trait("Category", "positive")] |
| NUnit | [Category("...")] | [Category("positive")] |
| TUnit | [Property("Category", "...")] | [Property("Category", "positive")] |
| JUnit 5 | @Tag("...") | @Tag("positive") |
| TestNG | @Test(groups = {"..."}) | @Test(groups = {"positive"}) |
| pytest | @pytest.mark.<name> | @pytest.mark.positive |
| RSpec | metadata after it | it "...", :positive do |
| Pester | -Tag '...' | It '...' -Tag 'positive' |
| Kotest | @Tags(...) | @Tags(Positive) |
| Swift Testing | @Tag(.<name>) | @Test(.tags(.positive)) |
| Catch2 | [tag] in name | TEST_CASE("...", "[positive]") |
| doctest | * doctest::test_suite("...") decorator | TEST_CASE("..." *doctest::test_suite("positive")) |
Record which tests already have tags to avoid duplication.
Step 3: Classify each test method
For each test method without traits, analyze:
- Method name -- names containing
Invalid,Fail,Error,Throw,Reject,BadInput,Null,None,Nil,Negative,raises_,_throws_,_returns_errorsuggestnegative - Assertion type --
Assert.ThrowsException/Assert.Throws/Should().Throw()/pytest.raises/expect(fn).toThrow/assertThrows/assert.Error(t, err)/expect { ... }.to raise_error/#[should_panic]/XCTAssertThrowsError/Should -Throw/EXPECT_THROWsuggestnegative - Input values --
null/None/nil/undefined,"",0,-1,int.MaxValue/sys.maxsize/Number.MAX_SAFE_INTEGER/math.MaxInt64/i32::MAX, empty collections suggestboundary - Setup complexity -- minimal setup with basic assertions suggests
smoke; external dependencies (file/db/net/env) suggestintegration - Comments and names -- references to issue numbers or "regression" / "bug" / "fix for #..." suggest
regression - Timing assertions --
Stopwatch,BenchmarkDotNet, elapsed-time checks; pytest-benchmark fixtures; benchmark.js; JMH@Benchmark;go test -bench; criterion.rs; XCTMetric; Google Benchmark; kotlinx-benchmark suggestperformance - Feature centrality -- tests on primary public API entry points or critical user workflows suggest
critical-path - Security patterns -- validates auth, checks permissions, sanitizes input, tests for injection, handles tokens/secrets suggest
security - Parallel/async constructs -- per-language concurrency primitives (see Trait Taxonomy table) suggest
concurrency - Fault injection -- simulates failures, tests retries, timeouts, or circuit breakers suggest
resilience - State mutation -- deletes external records, drops resources, modifies shared/global state suggest
destructive - Full-stack flow -- test spans entry point through data layer to final response, covering a complete user scenario suggest
end-to-end - Config/settings -- loads configuration, tests missing keys, validates options, checks environment variables suggest
configuration - Known instability -- test has skip / ignore annotations with comments about flakiness, or names contain "flaky" / "intermittent" suggest
flaky - Default -- if the test verifies a normal success path, tag
positive
When in doubt between positive and negative, read the assertion: if it asserts success -> positive; if it asserts failure -> negative.
Step 4: Apply trait attributes (or report only)
If the loaded language extension declares auto-edit for the framework, add the appropriate attribute to each test method. Place trait attributes adjacent to the existing test attribute. Examples:
MSTest:
[TestMethod]
[TestCategory("negative")]
[TestCategory("boundary")]
public void Parse_NullInput_ThrowsArgumentNullException() { ... }
xUnit:
[Fact]
[Trait("Category", "positive")]
[Trait("Category", "critical-path")]
public void CreateOrder_ValidItems_ReturnsConfirmation() { ... }
NUnit:
[Test]
[Category("regression")]
[Category("negative")]
public void Calculate_OverflowInput_ReturnsError() // Fix for #1234
{ ... }
pytest:
@pytest.mark.negative
@pytest.mark.boundary
def test_parse_none_input_raises_value_error():
...
JUnit 5:
@Test
@Tag("positive")
@Tag("critical-path")
void createOrder_validItems_returnsConfirmation() { ... }
TestNG:
@Test(groups = {"negative", "boundary"})
public void parse_nullInput_throwsIllegalArgumentException() { ... }
RSpec:
it "rejects null input", :negative, :boundary do
...
end
Pester:
It 'Rejects null input' -Tag 'negative','boundary' {
...
}
Kotest:
@Tags(Negative, Boundary)
class ParserSpec : StringSpec({
"rejects null input" { ... }
})
Swift Testing:
@Test(.tags(.negative, .boundary))
func parseNullInputThrows() throws { ... }
Catch2:
TEST_CASE("Parse null input throws", "[negative][boundary]") { ... }
If the loaded language extension declares report-only for the framework (Go standard testing, plain Jest/Vitest without convention, Rust without project-specific cfg, plain XCTest, plain GoogleTest, plain Mocha), do NOT modify source files. Instead emit a Markdown table mapping each test to its suggested tags, and recommend a project-wide convention the team can adopt (build tags, file suffix, describe-block prefix, GoogleTest filter prefix, test-plan grouping, etc.).
If the loaded language extension declares convention-based (e.g., Go //go:build integration, *_integration_test.go, GoogleTest INTEGRATION_* prefix), only emit canonical edits when the user has confirmed the project's convention. Otherwise treat as report-only.
Step 5: Generate trait summary
After tagging, produce a summary table:
## Trait Distribution
| Trait | Count | % of Total |
|---------------|-------|------------|
| positive | 42 | 53.8% |
| negative | 22 | 28.2% |
| boundary | 8 | 10.3% |
| critical-path | 12 | 15.4% |
| smoke | 3 | 3.8% |
| regression | 5 | 6.4% |
| integration | 4 | 5.1% |
| end-to-end | 2 | 2.6% |
| performance | 1 | 1.3% |
| security | 3 | 3.8% |
| concurrency | 2 | 2.6% |
| resilience | 1 | 1.3% |
| destructive | 1 | 1.3% |
| configuration | 2 | 2.6% |
| flaky | 1 | 1.3% |
| **Total tests** | **78** | -- |
Note: Percentages exceed 100% because tests can have multiple traits.
Include observations such as:
- Ratio of positive to negative tests
- Whether critical-path tests exist for key public APIs
- Any tests that could not be confidently classified (list them for manual review)
Validation
- Every test method has at least one trait classification (
positiveornegativeat minimum) — in the report forreport-onlyframeworks, or as an attribute forauto-editframeworks - No invented trait values outside the taxonomy table
- Existing trait attributes were preserved, not duplicated
- The trait summary table was generated
- For
auto-editframeworks, the project still builds / tests still discover after changes (dotnet build/pytest --collect-only/mvn test-compile/go vet ./.../cargo check --tests/npm run test:list/Invoke-Pester -PassThru -Skip/ equivalent) - For
report-onlyframeworks, no source files were modified - For
convention-basedframeworks, edits were applied ONLY when a project convention was confirmed
Common Pitfalls
| Pitfall | Solution |
|---|---|
| Guessing traits without reading the test body | Always read assertions and setup to classify accurately |
Tagging a test only as boundary without positive/negative | Every test should also be positive or negative -- boundary is additive |
| Using the wrong attribute syntax for the detected framework | Match the attribute style to the loaded language extension (don't put [TestCategory] in an xUnit project or @pytest.mark.x in a unittest test) |
| Duplicating an existing category attribute | Check for pre-existing traits in Step 2 before adding |
Over-tagging as critical-path | Reserve for tests on primary public entry points, not every helper |
| Editing Go / plain Jest / plain Rust / plain XCTest / plain GoogleTest source | These are report-only by default — emit a Markdown table instead. Only edit if the user confirms a project-wide convention (build tag, file suffix, describe-prefix, test-plan grouping). |
| Inventing tag prefixes for convention-based frameworks | Confirm the project's existing convention before adopting one — don't guess between _integration_test.go, //go:build integration, or IntegrationTest prefix |
| Missing language-specific concurrency / async primitives | Each language has its own primitives — read the loaded language extension and the Trait Taxonomy concurrency row before classifying as concurrency |