Ears Requirements

Overview

Transform requirement drafts into concise EARS-compliant statements, preserving intent while reducing ambiguity.

Workflow

1. Extract requirement intent from user input.
2. Identify the correct EARS pattern:
   • Ubiquitous
   • State-driven
   • Event-driven
   • Optional-feature
   • Unwanted-behavior
   • Complex combinations
3. Rewrite each requirement using strict clause order and one clear system response.
4. Run a quality pass for measurability, testability, and missing conditions.
5. Return:
   • Rewritten requirement(s)
   • Pattern label for each
   • Brief rationale if pattern choice could be disputed

Authoring Rules

• Keep one requirement per statement.
• Use exactly one explicit system subject (for example: “the ATM”).
• Use shall for mandatory behavior.
• Prefer observable outcomes over implementation details.
• Keep conditions explicit; avoid implied triggers or hidden states.
• Avoid weak phrases such as “as appropriate”, “if possible”, “etc.”.
• If numeric limits or timing are unknown, add a clear placeholder token (for example: <MAX_LATENCY_MS>).

EARS Clause Order

Apply only the clauses needed by the chosen pattern, always in this order:

While <state/precondition>, when <trigger>, the <system> shall <response>

Use unwanted behavior pattern as:

If <undesired trigger>, then the <system> shall <response>

For pattern definitions and examples, read references/ears-patterns.md.

Scripts

Use scripts/validate_ears.py to classify pattern and catch syntax/quality issues quickly.

Single requirement:

python3 scripts/validate_ears.py --requirement "When mute is selected, the laptop shall suppress all audio output."

Batch file (one requirement per line):

python3 scripts/validate_ears.py --file requirements.txt

Machine-readable output:

python3 scripts/validate_ears.py --file requirements.txt --json

Quality Gate

Before finalizing, verify each requirement:

• Is testable with a pass/fail criterion.
• Has unambiguous actor, condition, and response.
• Uses consistent terminology with no synonym drift.
• Avoids combining multiple independent behaviors unless explicitly complex.
• Matches the selected EARS pattern.

If any check fails, provide a corrected version and explain the minimal change made.