Mission Decomposition
Problem
Some jobs — writing thirteen concept files, or building a whole documentation site — are too big for any one agent session to finish in one go. Without a plan that breaks them into smaller pieces, agents either bite off more than their context window can hold or wander without direction and duplicate each other’s work.
Solution
Decompose large tasks into missions, each containing objectives that fit a single session (§9). The execution hierarchy is:
Campaign → Mission → Objective
(strategic) (tactical) (session-sized)Mission design rules:
| Principle | Rule |
|---|---|
| Session-sized objectives | Each objective must be completable in one agent session |
| Explicit deliverables | Every objective names a specific output file or artifact |
| Dependency ordering | Objectives list dependencies — what must be done first |
| Context budget | The mission declares what context to load, staying within the 75% rule |
| Claimability | Any agent can pick up any unclaimed objective with the mission file as briefing |
The decomposition process:
- Start with the campaign goal (e.g., “build a self-referential aDNA documentation vault”)
- Identify natural work boundaries (e.g., concepts, patterns, tutorials are different missions)
- Within each mission, list specific deliverables as objectives
- Order objectives by dependency (foundational concepts before advanced ones)
- Estimate context budget — if a mission needs more than ~15K tokens of domain context, it’s too broad
Handoff continuity: Each mission file contains enough context for a fresh agent to continue. The intent, objectives, context dependencies, and handoff notes create a self-contained briefing.
When to Use
- Any task expected to take more than one session
- Work that involves multiple related deliverables
- When coordination between sessions (or agents) is needed
- Campaign planning — every campaign is a set of missions
Example: This Vault
Operation Rosetta decomposes into 15 missions across 5 phases. Phase 1 alone has 5 missions:
| Mission | Objectives | Why Separate |
|---|---|---|
| M01 | 3 foundational concepts | Must exist before anything can cross-link to them |
| M02 | 4 governance concepts | Resolves M01 forward references |
| M03 | 6 advanced concepts | Builds on M01+M02 cross-linking targets |
| M04 | 8 patterns | Different template, different AGENTS.md rules |
| M05 | 5 comparisons | Requires full concept vocabulary from M01-M03 |
Each mission file (e.g., how/campaigns/campaign_rosetta/missions/mission_m04_pattern_library.md) lists specific files as objectives, declares context dependencies, and ends with handoff notes and an AAR. A fresh agent reading only the mission file can claim the next objective and begin work.
The decomposition also demonstrates convergence: the campaign scope (~100+ files) narrows to a mission scope (~8 files) narrows to a session objective (1 file at a time).
Anti-Pattern
Monolithic missions: A mission with 20 objectives spanning 5 sessions. By session 3, the agent has lost context on the mission’s intent. Split into smaller missions with clear boundaries.
Objectives without deliverables: “Research token optimization” is not an objective — it has no verifiable output. “Write concept_context_optimization.md” is an objective — the deliverable is the file.
Missing dependency ordering: Writing advanced concepts before foundational ones, then discovering forward references can’t be resolved. Map dependencies before starting.
Skipping the AAR: Completing a mission without the 5-line After-Action Review. The AAR captures what worked, what didn’t, and what the next mission should know. Without it, the same mistakes repeat.
Related
- Convergence Model — the structural principle that makes decomposition necessary and effective
- Token Selection — the context budget discipline that sizes objectives to sessions
- AGENTS.md Routing — how agents navigate to their mission’s working files