Golang Code Style

[
  {
    "id": 1,
    "name": "zero-value-intent-signal",
    "description": "var vs := signals intent: var for zero-value start, := for non-zero — even when the zero value IS the business default",
    "prompt": "Write a Go file `session.go` in package `session`. Create a Session struct with fields: userID string, requestCount int, isAuthenticated bool, lastError error, startedAt time.Time, tags []string. Add a constructor NewSession(userID string) that initializes the struct. In the constructor, requestCount starts at zero (it will be incremented on each use), isAuthenticated starts false (it must be explicitly set after login), lastError starts nil, startedAt is set to time.Now(), and tags is initialized as an empty slice. Also add a local variable inside a method Describe() that builds a description string from a fixed prefix 'session:'.",
    "trap": "Model uses := for all fields including zero-value ones (requestCount := 0, isAuthenticated := false) or uses var for non-zero assignments like startedAt, obscuring intent",
    "assertions": [
      {
        "id": "1.1",
        "text": "requestCount is NOT explicitly initialized to 0 in the constructor — the zero value is relied upon via var or struct literal without that field, not via requestCount := 0"
      },
      {
        "id": "1.2",
        "text": "startedAt uses := assignment (startedAt := time.Now() or field assignment) — NOT var startedAt time.Time followed by assignment — because it has a non-zero meaningful value"
      },
      {
        "id": "1.3",
        "text": "The fixed prefix string variable in Describe() uses := (prefix := 'session:') — not var prefix string = 'session:'"
      },
      {
        "id": "1.4",
        "text": "tags is initialized with []string{} or make([]string, 0) — never nil — because nil slices serialize to null in JSON"
      }
    ]
  },
  {
    "id": 2,
    "name": "empty-slice-map-not-nil",
    "description": "Empty collections initialized as []T{} or make(), never nil",
    "prompt": "Write a Go file `handler.go` in package `api`. Create a Handler struct. Add a method ListUsers that returns a slice of User structs (define User with Name and Email fields). Add a method GetTags that returns a map[string]string. Both methods should return empty collections when there's no data. Add a method BuildResponse that takes a slice of results and a map of metadata and processes them.",
    "trap": "Model returns nil slices/maps or uses uninitialized var declarations for empty collections, causing nil != empty issues in JSON serialization and caller code",
    "assertions": [
      {
        "id": "2.1",
        "text": "Empty slice return uses []User{} or make([]User, 0) — never returns nil or an uninitialized var declaration without assignment"
      },
      {
        "id": "2.2",
        "text": "Empty map return uses map[string]string{} or make(map[string]string) — never returns nil or an uninitialized var declaration without assignment"
      },
      {
        "id": "2.3",
        "text": "When capacity is known (e.g., from len(input)), make() with capacity hint is used for preallocating slices or maps"
      }
    ]
  },
  {
    "id": 3,
    "name": "named-struct-fields-nested",
    "description": "All struct literals use named fields, including nested and anonymous structs",
    "prompt": "Write a Go file `middleware.go` in package `middleware`. Create a RateLimiter struct with fields: windowSize time.Duration, maxRequests int, perIP bool. Create a middleware chain config using a struct literal with nested structs: a TimeoutConfig containing duration and errorMessage, a RetryConfig containing maxAttempts int and backoff time.Duration, and a CircuitBreakerConfig containing threshold float64 and resetAfter time.Duration. Instantiate each of these structs as part of a larger MiddlewareConfig struct. Also create a tls.Config with MinVersion and a list of cipher suites.",
    "trap": "Model uses positional struct literals for the