Subtask Creation - Bite-Sized, Zero-Context Steps

Overview

Write comprehensive implementation subtasks assuming the engineer has zero context for our codebase. Each subtask breaks down into 2-5 minute steps following RED-GREEN-REFACTOR. Complete code, exact commands, explicit verification. DRY. YAGNI. TDD. Frequent commits.

Save subtasks to: docs/pre-dev/{feature-name}/subtasks/T-[task-id]/ST-[task-id]-[number]-[description].md

Foundational Principle

Every subtask must be completable by anyone with zero context about the system.

Requiring context creates bottlenecks, onboarding friction, and integration failures.

Subtasks answer: Exactly what to create/modify, with complete code and verification. Subtasks never answer: Why the system works this way (context is removed).

Bite-Sized Step Granularity

Each step is one action (2-5 minutes):

"Write the failing test" - step
"Run it to make sure it fails" - step
"Implement the minimal code to make the test pass" - step
"Run the tests and make sure they pass" - step
"Commit" - step

Subtask Document Structure

Header (required):

| Field | Content | |-------|---------| | Title | # ST-[task-id]-[number]: [Subtask Name] | | Agent Note | > **For Agents:** REQUIRED SUB-SKILL: Use ring:executing-plans | | Goal | One sentence describing what this builds | | Prerequisites | Verification commands with expected output | | Files | Create: exact/path, Modify: exact/path:lines, Test: tests/path |

Step Structure (TDD Cycle):

| Step | Content | |------|---------| | Step 1: Write failing test | Complete test file with imports | | Step 2: Run test to verify fail | Command + expected failure output | | Step 3: Write minimal implementation | Complete implementation file | | Step 4: Run test to verify pass | Command + expected success output | | Step 5: Update exports (if needed) | Exact modification to index files | | Step 6: Verify type checking | Command + expected output | | Step 7: Commit | Exact git commands with message | | Rollback | Exact commands to undo if issues |

Explicit Rules

✅ DO Include in Subtasks

Exact file paths (absolute or from root), complete file contents (if creating), complete code snippets (if modifying), all imports and dependencies, step-by-step TDD cycle (numbered), verification commands (copy-pasteable), expected output (exact), rollback procedures (exact commands), prerequisites (what must exist first)

❌ NEVER Include in Subtasks

Placeholders: "...", "TODO", "implement here"; vague instructions: "update the service", "add validation"; assumptions: "assuming setup is done"; context requirements: "you need to understand X first"; incomplete code: "add the rest yourself"; missing imports: "import necessary packages"; undefined success: "make sure it works"; no verification: "test it manually"

<cannot_skip>

⛔ HARD GATE: lib-commons in Go Code Examples

MUST: For Go projects, code examples use lib-commons instead of custom utilities.

See shared-patterns/code-example-standards.md for:

Complete list of what lib-commons provides
Forbidden patterns (custom loggers, config loaders, HTTP helpers)
Correct import patterns with lib prefix aliases
Anti-rationalization table

Quick Reference - DO NOT Create Custom:

| Category | Use lib-commons | |----------|-----------------| | Logging | libLog "github.com/LerianStudio/lib-commons/v2/commons/log" | | Config | libCommons.SetConfigFromEnvVars() | | HTTP | libHTTP "github.com/LerianStudio/lib-commons/v2/commons/net/http" | | Telemetry | libOpentelemetry "github.com/LerianStudio/lib-commons/v2/commons/opentelemetry" | | PostgreSQL | libPostgres "github.com/LerianStudio/lib-commons/v2/commons/postgres" |

MUST NOT: Create custom logger, config loader, or HTTP helper in subtasks—use lib-commons.

</cannot_skip>

Rationalization Table

| Excuse | Reality | |--------|---------| | "The developer will figure out imports" | Imports are context. Provide them explicitly. | | "TODO comments are fine for simple parts" | TODOs require decisions. Make them now. | | "They'll know which service to update" | They won't. Specify the exact file path. | | "The verification steps are obvious" | Obvious ≠ documented. Write exact commands. | | "Rollback isn't needed for simple changes" | Simple changes fail too. Always provide rollback. | | "This needs system understanding" | Then you haven't removed context. Simplify more. | | "I'll provide the template, they fill it" | Templates are incomplete. Provide full code. | | "The subtask description explains it" | Descriptions need interpretation. Give exact steps. | | "They can look at similar code for reference" | That's context. Make subtask self-contained. | | "This is too detailed, we're not that formal" | Detailed = parallelizable = faster. Be detailed. | | "Steps are too small, feels like hand-holding" | Small steps = verifiable progress. Stay small. | | "Custom logger is simpler for this example" | Examples teach patterns. Teach lib-commons. | | "lib-commons import is too verbose" | Verbosity shows correct dependencies. Keep it. | | "I'll use lib-commons in the real code" | Subtask is real code. Use lib-commons now. |

Red Flags - STOP

If you catch yourself writing any of these in a subtask, STOP and rewrite:

Code placeholders: ..., // TODO, // implement X here
Vague file references: "the user service", "the auth module"
Assumption phrases: "assuming you have", "make sure you"
Incomplete imports: "import required packages"
Missing paths: Not specifying where files go
Undefined verification: "test that it works"
Steps longer than 5 minutes
Context dependencies: "you need to understand X"
No TDD cycle in implementation steps
Use libZap.NewLogger() instead of custom func NewLogger() (Go)
Use libCommons.SetConfigFromEnvVars() instead of scattered os.Getenv() (Go)
Use libHTTP utilities instead of custom func JSONResponse() (Go)
Check lib-commons first before creating files in utils/, helpers/, pkg/common/ (Go)

When you catch yourself: Expand the subtask until it's completely self-contained.

Gate 8 Validation Checklist

| Category | Requirements | |----------|--------------| | Atomicity | Each step 2-5 minutes; no system architecture understanding required; assignable to anyone | | Completeness | All code provided in full; all file paths explicit; all imports listed; all prerequisites documented; TDD cycle followed | | Verifiability | Test commands copy-pasteable; expected output exact; commands run from project root | | Reversibility | Rollback commands provided; rollback doesn't require system knowledge |

Gate Result: ✅ PASS → Ready for implementation | ⚠️ CONDITIONAL (add details) | ❌ FAIL (decompose further)

Confidence Scoring

| Factor | Points | Criteria | |--------|--------|----------| | Step Atomicity | 0-30 | All 2-5 minutes: 30, Most sized right: 20, Too large/vague: 10 | | Code Completeness | 0-30 | Zero placeholders: 30, Mostly complete: 15, Significant TODOs: 5 | | Context Independence | 0-25 | Anyone can execute: 25, Minor context: 15, Significant knowledge: 5 | | TDD Coverage | 0-15 | All RED-GREEN-REFACTOR: 15, Most have tests: 10, Limited: 5 |

Action: 80+ autonomous | 50-79 present options | <50 ask about structure

Execution Handoff

After creating subtasks, offer execution choice:

"Subtasks complete. Two execution options:

Subagent-Driven - Fresh subagent per subtask, review between, fast iteration → Use ring:subagent-driven-development
Parallel Session - New session with ring:executing-plans, batch with checkpoints → Use ring:executing-plans

Which approach?"

The Bottom Line

If you wrote a subtask with "TODO" or "..." or "add necessary imports", delete it and rewrite with complete code.

Subtasks are not instructions. Subtasks are complete, copy-pasteable implementations following TDD.

"Add validation" is not a step. [Complete validation code with test] is a step.
"Update the service" is not a step. [Exact file path + exact code changes with test] is a step.
"Import necessary packages" is not a step. [Complete list of imports] is a step.

Every subtask must be completable by someone who:

Just joined the team yesterday
Has never seen the codebase before
Doesn't know the business domain
Won't ask questions (you're unavailable)
Follows TDD religiously

If they can't complete it with zero questions while following RED-GREEN-REFACTOR, it's not atomic enough.

Remember: DRY. YAGNI. TDD. Frequent commits.

Standards Loading (MANDATORY)

This skill creates implementation subtasks. While it does NOT require direct WebFetch of standards, subtasks MUST reference lib-commons patterns for Go projects.

For Go projects: All code examples in subtasks MUST use lib-commons imports. See shared-patterns/code-example-standards.md for required patterns.

HARD GATE: Subtasks with custom logger, config loader, or HTTP helper implementations are INVALID. Use lib-commons.

Blocker Criteria - STOP and Report

| Condition | Action | Severity | |-----------|--------|----------| | Tasks (Gate 7) not validated | STOP and complete Gate 7 first | CRITICAL | | Subtask contains TODO or placeholder | STOP and expand with complete code | HIGH | | Subtask requires context not provided | STOP and add missing context to subtask | HIGH | | Step exceeds 5 minutes | STOP and break into smaller steps | MEDIUM | | Missing TDD cycle (no RED phase) | STOP and add failing test first | HIGH | | Go subtask uses custom logger instead of lib-commons | STOP and replace with lib-commons | HIGH |

Cannot Be Overridden

These requirements are NON-NEGOTIABLE:

MUST NOT include placeholders (TODO, ..., "implement here")
MUST NOT include vague instructions ("update the service")
MUST provide complete file paths (absolute or from root)
MUST provide all imports explicitly
MUST follow TDD cycle: RED (failing test) → GREEN (implementation) → REFACTOR
MUST include verification commands with expected output
MUST include rollback procedures
MUST use lib-commons for Go code examples (no custom utilities)

Severity Calibration

| Severity | Definition | Example | |----------|------------|---------| | CRITICAL | Subtask cannot be executed | Missing prerequisite, no file paths | | HIGH | Subtask requires interpretation | TODO placeholder, vague description | | MEDIUM | Subtask quality degraded | Missing verification command | | LOW | Minor documentation gaps | Rollback could be more detailed |

Pressure Resistance

| User Says | Your Response | |-----------|---------------| | "Developer will figure out imports" | "Cannot assume imports. Imports ARE context. I'll provide explicit import statements." | | "TODO comments are fine for simple parts" | "Cannot use TODOs. TODOs require decisions. I'll make those decisions now and provide complete code." | | "Steps are too detailed, feels like hand-holding" | "Cannot reduce detail. Small steps = verifiable progress. Detail enables parallelization." | | "Skip TDD for this simple change" | "Cannot skip TDD. Every subtask follows RED-GREEN-REFACTOR. I'll write the failing test first." | | "Custom logger is simpler for this example" | "Cannot use custom logger. Subtasks teach patterns. lib-commons is the pattern." |

When This Skill Is Not Needed

Small Track workflow (execute tasks directly without subtask breakdown)
Tasks are simple enough without fine-grained breakdown
Tasks (Gate 7) not yet validated (complete Gate 7 first)
Implementation already in progress (use ring:executing-plans)
Proof-of-concept work without formal process needs