Taskmaster — v5 Task Protocol

Purpose

Taskmaster is the default execution protocol for multi-step Codex work. v5 keeps the existing Debug-First core while expanding the skill into three task shapes:

• Single Task — one deliverable, one shared context
• Epic Task — multiple child tasks with dependencies
• Batch Task — homogeneous row-level work executed through spawn_agents_on_csv

Core Principles

1. The current truth artifact on disk wins over memory.
2. No step, subtask, or batch row becomes DONE without explicit validation.
3. Keep verbose reasoning in PROGRESS.md, EPIC.md, or batch output files, not in the chat.
4. Keep failures visible. Do not silently downgrade to manual or serial execution.
5. Keep planning CSVs and batch worker CSVs separate.
6. Build for Codex-only recovery: a cold restart must be resumable from files alone.

Shape Router

Shape	Use when	Truth artifacts	Example
Single Task	One deliverable with shared context	TODO.csv or SPEC.md + TODO.csv + PROGRESS.md	Fix one OAuth redirect bug
Epic Task	Multiple deliverables, modules, or dependency chains	EPIC.md + SUBTASKS.csv + PROGRESS.md	Ship billing dashboard across API, UI, docs
Batch Task	Same instruction template across independent rows	TODO.csv + batch/BATCH.md + workers-input.csv + workers-output.csv	Audit 80 Markdown files for frontmatter

Router Rules

• Start with Single Task when the user wants one deliverable and progress can stay in one shared context.
• Promote to Epic Task when one TODO.csv starts carrying phases, subprojects, or independent deliverables.
• Use Batch Task only when rows are independent, share one instruction template, and success can be expressed in structured output fields.
• An Epic Task can contain single-compact, single-full, or batch child tasks.
• A Batch Task must not be used for heterogeneous roles, cross-row dependencies, or shared write scopes.

Single Task

Single Task preserves backward compatibility with the old LITE/FULL behavior by supporting two execution profiles.

Compact Single

Use Compact Single when the task is short, linear, and does not need recovery logs or cached research artifacts.

• Files: project-root TODO.csv only
• Template: compact_todo_template.csv
• Status set: TODO | IN_PROGRESS | DONE
• Best for: short documentation edits, tiny cleanup passes, quick rename tasks

Compact Single example:

id,task,status,completed_at,notes
1,Locate root cause,IN_PROGRESS,,
2,Implement fix,TODO,,
3,Run verification,TODO,,

Full Single

Use Full Single for all code changes, long-running tasks, or any work that must survive a context reset. This is the default single-task path.

• Files: .codex-tasks/<task-name>/SPEC.md, TODO.csv, PROGRESS.md, raw/
• Templates:
  • SPEC_TEMPLATE.md
  • PROGRESS_TEMPLATE.md
  • todo_template.csv
  • perf_todo_template.csv
• Status set: TODO | IN_PROGRESS | DONE | FAILED
• Best for: code implementation, bug fixes, refactors, multi-hour work

Full Single directory example:

.codex-tasks/20260313-auth-fix/
├── SPEC.md
├── TODO.csv
├── PROGRESS.md
└── raw/

Single Task Rules

• Re-read the active TODO.csv before every new step.
• Keep TODO.csv leaf-level only. Do not store phases, child projects, or batch rows there.
• Use echo SKIP only when validation cannot be automated, and record why.
• If retries hit 5, change strategy explicitly or promote the task shape.

Epic Task

Epic Task is the parent coordination shape for large work that spans multiple deliverables or dependency chains.

• Files:
  • .codex-tasks/<epic-name>/EPIC.md
  • .codex-tasks/<epic-name>/SUBTASKS.csv
  • .codex-tasks/<epic-name>/PROGRESS.md
  • .codex-tasks/<epic-name>/tasks/<child-task>/...
• Templates:
  • EPIC_TEMPLATE.md
  • subtasks_template.csv
• Status set: TODO | IN_PROGRESS | DONE | FAILED
• Best for: multi-module features, staged refactors, long projects with clear child deliverables

Epic directory example:

.codex-tasks/20260313-billing-epic/
├── EPIC.md
├── SUBTASKS.csv
├── PROGRESS.md
└── tasks/
    ├── 20260313-api/
    ├── 20260313-frontend/
    └── 20260313-docs/

Epic workflow:

1. Define the global goal and delivery boundary in EPIC.md.
2. Register child tasks in SUBTASKS.csv with task_type, dependencies, and task_dir.
   • depends_on: use ; to list multiple dependency IDs (e.g., 1;2). Empty means no dependency.
3. Execute each child task with its own Single or Batch protocol.
4. Bubble child validation back to SUBTASKS.csv and parent PROGRESS.md.
5. Close the Epic only when all child rows are DONE and the final validation passes.

Use Epic instead of a single TODO.csv when one task file starts reading like project management instead of execution.

Batch Task

Batch Task is for homogeneous row-level work that should be executed through spawn_agents_on_csv. It can be a standalone task or a child inside an Epic.

• Files:
  • .codex-tasks/<task-name>/SPEC.md
  • .codex-tasks/<task-name>/TODO.csv for 3-5 high-level steps
  • .codex-tasks/<task-name>/PROGRESS.md
  • .codex-tasks/<task-name>/batch/BATCH.md
  • .codex-tasks/<task-name>/batch/workers-input.csv
  • .codex-tasks/<task-name>/batch/workers-output.csv
  • .codex-tasks/<task-name>/raw/
• Templates:
  • BATCH_TEMPLATE.md
  • workers_input_template.csv
  • workers_output_template.csv
• Best for: bulk file audits, bulk metadata updates, structured per-row analysis

Batch directory example:

.codex-tasks/20260313-doc-audit/
├── SPEC.md
├── TODO.csv
├── PROGRESS.md
├── batch/
│   ├── BATCH.md
│   ├── workers-input.csv
│   └── workers-output.csv
└── raw/

Batch Eligibility Checklist

Only use Batch Task when all of the following are true:

• One instruction template can describe every row.
• Rows are independent and can be retried independently.
• Output can be expressed as structured fields in output_schema.
• Writes are disjoint, or the batch is read-only.

Batch Lifecycle

1. Identify a parent TODO.csv step that is truly row-level and homogeneous.
2. Create batch/BATCH.md and define:
   • instruction template
   • id_column
   • output_schema
   • max_workers
   • max_runtime_seconds
   • output_csv_path
3. Build workers-input.csv from real artifacts, not from plan steps.
4. Run spawn_agents_on_csv with explicit id_column, output_schema, max_workers, max_runtime_seconds, and output_csv_path.
5. Inspect workers-output.csv. Failed rows remain visible and may be retried with a filtered input CSV.
6. Merge the aggregate result into parent PROGRESS.md and only then mark the parent step DONE.

Example Batch step sequence:

id,task,status,acceptance_criteria,validation_command,completed_at,retry_count,notes
1,Build workers-input.csv,IN_PROGRESS,batch/workers-input.csv exists,test -f batch/workers-input.csv,,0,
2,Run spawn_agents_on_csv,TODO,batch/workers-output.csv exists,test -f batch/workers-output.csv,,0,
3,Merge row results,TODO,Failed rows are handled and summary is written,test -f PROGRESS.md,,0,

Mixed Shapes

• A Single Task can promote to Epic when one execution stream stops being coherent.
• A Single or Epic child step can delegate homogeneous work to Batch.
• Use the current layer's truth file only:
  • TODO.csv for step planning
  • SUBTASKS.csv for child-task state
  • workers-output.csv for row results

Mid-Task Shape Promotion

When complexity outgrows the current shape, promote in-place:

Single → Epic

1. Create .codex-tasks/<task-name>/EPIC.md from the existing SPEC.md goal.
2. Convert remaining TODO.csv rows into child task entries in SUBTASKS.csv.
3. Move the original SPEC.md, TODO.csv, PROGRESS.md into tasks/<original-task>/ as the first child.
4. Create new child directories for the additional deliverables.
5. Log the promotion reason in the parent PROGRESS.md.

Single/Epic Step → Batch

1. Identify the TODO.csv or SUBTASKS.csv row that is actually N homogeneous items.
2. Replace it with a 3-step Batch sequence: build input → run workers → merge results.
3. Create batch/ directory with BATCH.md and workers-input.csv.
4. The parent step stays IN_PROGRESS until the batch merge completes.
5. Log the delegation in PROGRESS.md.

Validation Rules

• Re-read the active truth file before every new step.
• No parent task can claim success while a child subtask or batch row still fails its merge criteria.
• Keep retry counts explicit.
• Keep raw fetched material under raw/ for Full, Epic, and Batch shapes.
• If the work is heterogeneous, use a dedicated multi-agent flow instead of forcing it into Batch.

Context Recovery Protocol

Use the smallest artifact set that fully restores state:

• Compact Single: read TODO.csv, resume from the first non-DONE row.
• Full Single: read SPEC.md, TODO.csv, then the PROGRESS.md recovery block.
• Epic Task: read EPIC.md, SUBTASKS.csv, parent PROGRESS.md, then the current child task directory.
• Batch Task: read SPEC.md, TODO.csv, batch/BATCH.md, batch/workers-output.csv, then the PROGRESS.md recovery block.

Every recovery message must include:

1. 任务: goal
2. 形态: single-compact | single-full | epic | batch
3. 进度: X/Y
4. 当前: current step, child task, or failed row set
5. 文件: active truth artifact path
6. 下一步: exact next action

Output Contract

Every status update must include:

1. 任务: one-line goal
2. 形态: current task shape
3. 进度: X/Y steps or rows complete
4. 当前: active step, child task, or batch stage
5. 验证: latest validation command and result
6. 文件: active task directory or truth artifact

References

• SPEC_TEMPLATE.md
• PROGRESS_TEMPLATE.md
• todo_template.csv
• perf_todo_template.csv
• compact_todo_template.csv
• EPIC_TEMPLATE.md
• BATCH_TEMPLATE.md
• subtasks_template.csv
• workers_input_template.csv
• workers_output_template.csv
• EXAMPLES.md