---
description: Execute spec tasks using TDD methodology
allowed-tools: Bash, Read, Write, Edit, MultiEdit, Grep, Glob, LS, WebFetch, WebSearch
argument-hint: <feature-name> [task-numbers]
---
# Implementation Task Executor
<background_information>
- **Mission**: Execute implementation tasks using Test-Driven Development methodology based on approved specifications
- **Success Criteria**:
- All tests written before implementation code
- Code passes all tests with no regressions
- Tasks marked as completed in tasks.md
- Implementation aligns with design and requirements
</background_information>
<instructions>
## Core Task
Execute implementation tasks for feature **$1** using Test-Driven Development.
## Execution Steps
### Step 1: Load Context
**Read all necessary context**:
- `.kiro/specs/$1/spec.json`, `requirements.md`, `design.md`, `tasks.md`
- **Entire `.kiro/steering/` directory** for complete project memory
**Validate approvals**:
- Verify tasks are approved in spec.json (stop if not, see Safety & Fallback)
### Step 2: Select Tasks
**Determine which tasks to execute**:
- If `$2` provided: Execute specified task numbers (e.g., "1.1" or "1,2,3")
- Otherwise: Execute all pending tasks (unchecked `- [ ]` in tasks.md)
### Step 3: Execute with TDD
For each selected task, follow Kent Beck's TDD cycle:
1. **RED - Write Failing Test**:
- Write test for the next small piece of functionality
- Test should fail (code doesn't exist yet)
- Use descriptive test names
2. **GREEN - Write Minimal Code**:
- Implement simplest solution to make test pass
- Focus only on making THIS test pass
- Avoid over-engineering
3. **REFACTOR - Clean Up**:
- Improve code structure and readability
- Remove duplication
- Apply design patterns where appropriate
- Ensure all tests still pass after refactoring
4. **VERIFY - Validate Quality**:
- All tests pass (new and existing)
- No regressions in existing functionality
- Code coverage maintained or improved
5. **MARK COMPLETE**:
- Update checkbox from `- [ ]` to `- [x]` in tasks.md
## Critical Constraints
- **TDD Mandatory**: Tests MUST be written before implementation code
- **Task Scope**: Implement only what the specific task requires
- **Test Coverage**: All new code must have tests
- **No Regressions**: Existing tests must continue to pass
- **Design Alignment**: Implementation must follow design.md specifications
</instructions>
## Tool Guidance
- **Read first**: Load all context before implementation
- **Test first**: Write tests before code
- Use **WebSearch/WebFetch** for library documentation when needed
## Output Description
Provide brief summary in the language specified in spec.json:
1. **Tasks Executed**: Task numbers and test results
2. **Status**: Completed tasks marked in tasks.md, remaining tasks count
**Format**: Concise (under 150 words)
## Safety & Fallback
### Error Scenarios
**Tasks Not Approved or Missing Spec Files**:
- **Stop Execution**: All spec files must exist and tasks must be approved
- **Suggested Action**: "Complete previous phases: `/kiro:spec-requirements`, `/kiro:spec-design`, `/kiro:spec-tasks`"
**Test Failures**:
- **Stop Implementation**: Fix failing tests before continuing
- **Action**: Debug and fix, then re-run
### Task Execution
**Execute specific task(s)**:
- `/kiro:spec-impl $1 1.1` - Single task
- `/kiro:spec-impl $1 1,2,3` - Multiple tasks
**Execute all pending**:
- `/kiro:spec-impl $1` - All unchecked tasks
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