---

name: speckit-08-implement description: Execute implementation plan by processing all tasks in tasks.md

Spec-Kit Implement

Execute the implementation plan by processing and executing all tasks defined in tasks.md.

User Input

$ARGUMENTS

You MUST consider the user input before proceeding (if not empty).

Constitution Loading (REQUIRED)

Before ANY action, load and internalize the project constitution:

1. Read constitution:

   cat .specify/memory/constitution.md 2>/dev/null || echo "NO_CONSTITUTION"
   

2. If file doesn't exist:

   ERROR: Project constitution not found at .specify/memory/constitution.md
   
   Cannot proceed without constitution.
   Run: /speckit-00-constitution
   

3. Parse all principles, constraints, and governance rules.

4. Extract Enforcement Rules: Find all MUST, MUST NOT, SHALL, REQUIRED, NON-NEGOTIABLE statements. These rules are checked BEFORE EVERY FILE WRITE.

5. Hard Gate Declaration:

   CONSTITUTION ENFORCEMENT GATE ACTIVE
   Extracted: X enforcement rules
   Mode: STRICT - violations HALT implementation
   

Prerequisites Check

1. Run prerequisites check:

   .tessl/tiles/tessl-labs/spec-kit/skills/speckit-01-specify/scripts/bash/check-prerequisites.sh --json --require-tasks --include-tasks
   

2. Parse JSON for FEATURE_DIR and AVAILABLE_DOCS.

3. If error or missing tasks.md:

   ERROR: tasks.md not found in feature directory.
   Run: /speckit-06-tasks
   

Pre-Implementation Validation

BEFORE any implementation, perform complete validation sweep:

Artifact Completeness Check

Artifact	Required	Check
constitution.md	YES	Has principles section
spec.md	YES	Has Requirements + Success Criteria
plan.md	YES	Has Technical Context defined
tasks.md	YES	Has at least one task
checklists/*.md	YES	At least one checklist

Cross-Artifact Consistency

1. Spec → Tasks: Every FR-XXX should have corresponding task(s)
2. Plan → Tasks: Tech stack should match task file paths
3. Constitution → Plan: Verify no constitution violations

Readiness Score

Report: Artifacts complete, Spec coverage %, Plan alignment, Constitution compliance, Checklist status, Dependencies valid. Output READY or BLOCKED.

Checklist Gating (CRITICAL)

1. Read each checklist file in FEATURE_DIR/checklists/
2. Count: Incomplete (- [ ]) vs Complete (- [x])
3. PASS: All checklists 100% → proceed
4. FAIL: Ask user to proceed or halt

Execution Flow

1. Load Implementation Context

• REQUIRED: tasks.md, plan.md
• IF EXISTS: data-model.md, contracts/, research.md, quickstart.md, tests/test-specs.md

2. TDD Support Check

If tests/test-specs.md exists:

• Verify assertion integrity using .tessl/tiles/tessl-labs/spec-kit/skills/speckit-01-specify/scripts/bash/testify-tdd.sh comprehensive-check
• BLOCKED if assertions were tampered → halt with remediation steps
• Display circular verification warning: fix code to pass tests, don't modify assertions

If TDD is mandatory in constitution but test-specs.md missing → ERROR

3. Tessl Integration

If Tessl installed, use tiles for library documentation. See references/tessl-integration.md for detailed patterns.

Key rule: Before implementing code using a tile's library, query mcp__tessl__query_library_docs.

4. Project Setup

Create/verify ignore files based on tech stack. See references/ignore-patterns.md for patterns by technology.

5. Parse and Execute Tasks

Extract from tasks.md:

• Task phases, dependencies, parallel markers [P]
• Execute phase-by-phase, respecting dependencies
• Parallel tasks [P] can run together

Execution rules:

• Query Tessl tiles before implementing library code
• Tests before code if TDD
• Mark completed tasks as [x]

6. Output Validation (REQUIRED)

Before writing ANY file:

1. Review against EACH constitutional principle
2. If violation: STOP, explain, suggest alternative
3. If compliant: proceed

7. Progress Tracking

• Report after each task
• Halt on non-parallel task failure
• Mark completed tasks [x] in tasks.md

8. Completion

• Verify all tasks completed
• Validate features match spec
• Confirm tests pass
• Report Tessl tile usage if applicable

Error Handling

Condition	Response
Tasks file missing	STOP: Run /speckit-06-tasks
Plan file missing	STOP: Run /speckit-03-plan
Constitution violation	STOP, explain, suggest alternative
Checklist incomplete	Ask user, STOP if declined
Task fails	Report error, halt sequential

Next Steps

Implementation complete! Next steps:
- Run tests to verify functionality
- Commit and push changes
- /speckit-09-taskstoissues - (Optional) Export tasks to GitHub Issues