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):
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"Write the failing test" - step
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"Run it to make sure it fails" - step
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"Implement the minimal code to make the test pass" - step
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"Run the tests and make sure they pass" - step
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"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:
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Complete list of what lib-commons provides
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Forbidden patterns (custom loggers, config loaders, HTTP helpers)
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Correct import patterns with lib prefix aliases
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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:
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Code placeholders: ... , // TODO , // implement X here
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Vague file references: "the user service", "the auth module"
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Assumption phrases: "assuming you have", "make sure you"
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Incomplete imports: "import required packages"
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Missing paths: Not specifying where files go
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Undefined verification: "test that it works"
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Steps longer than 5 minutes
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Context dependencies: "you need to understand X"
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No TDD cycle in implementation steps
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Use libZap.NewLogger() instead of custom func NewLogger() (Go)
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Use libCommons.SetConfigFromEnvVars() instead of scattered os.Getenv() (Go)
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Use libHTTP utilities instead of custom func JSONResponse() (Go)
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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:
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Subagent-Driven - Fresh subagent per subtask, review between, fast iteration → Use ring:subagent-driven-development
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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.
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"Add validation" is not a step. [Complete validation code with test] is a step.
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"Update the service" is not a step. [Exact file path + exact code changes with test] is a step.
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"Import necessary packages" is not a step. [Complete list of imports] is a step.
Every subtask must be completable by someone who:
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Just joined the team yesterday
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Has never seen the codebase before
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Doesn't know the business domain
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Won't ask questions (you're unavailable)
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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:
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MUST NOT include placeholders (TODO, ..., "implement here")
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MUST NOT include vague instructions ("update the service")
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MUST provide complete file paths (absolute or from root)
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MUST provide all imports explicitly
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MUST follow TDD cycle: RED (failing test) → GREEN (implementation) → REFACTOR
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MUST include verification commands with expected output
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MUST include rollback procedures
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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
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Small Track workflow (execute tasks directly without subtask breakdown)
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Tasks are simple enough without fine-grained breakdown
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Tasks (Gate 7) not yet validated (complete Gate 7 first)
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Implementation already in progress (use ring:executing-plans)
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Proof-of-concept work without formal process needs