name: tiered-memory description: Three-tier agent memory model (hot/cold/wiki) for 20-55% context reduction per spawn domain: memory-management, performance confidence: high
source: earned (production measurements in tamirdresher/tamresearch1, 34-74KB baseline payloads)
Skill: Tiered Agent Memory
Overview
Squad agents currently load their full context history on every spawn, resulting in 34–74KB payloads per agent (8,800–18,500 tokens). Measurement shows 82–96% of that context is "old noise" — information that is no longer relevant to the current task. The Tiered Agent Memory skill introduces a three-tier memory model that eliminates this bloat, achieving 20–55% context reduction per spawn in production.
Memory Tiers
🔥 Hot Tier — Current Session Context
- Size target: ~2–4KB
- Load policy: Always loaded. Every spawn includes hot memory by default.
- Contents: Current task description, active decisions made this session, immediate blockers, last 3–5 actions taken, who you are talking to right now.
- Lifetime: Current session only. Discarded after session ends (Scribe promotes relevant parts to Cold).
- Purpose: Provide immediate task context without any latency or load decision.
❄️ Cold Tier — Summarized Cross-Session History
- Size target: ~8–12KB
- Load policy: Load on demand. Include only when the task explicitly needs history.
- Contents: Summarized past sessions (compressed by Scribe), cross-session decisions, recurring patterns, unresolved issues from prior work.
- Lifetime: 30 days rolling window. After 30 days, Scribe promotes to Wiki tier.
- Purpose: Answer "what have we tried before?" and "what was decided?" without replaying full transcripts.
- How to include: Pass
--include-coldin spawn template or add## Cold Memorysection.
📚 Wiki Tier — Durable Structured Knowledge
- Size target: variable, structured reference docs
- Load policy: Async write, selective read. Load only when task requires domain knowledge.
- Contents: Architecture decisions (ADRs), agent charters, routing rules, stable conventions, external API contracts, known platform constraints.
- Lifetime: Permanent until explicitly deprecated.
- Purpose: Authoritative reference. Not history — structured facts.
- How to include: Pass
--include-wikior reference specific wiki doc paths in spawn template.
When to Load Each Tier
| Situation | Hot | Cold | Wiki |
|---|---|---|---|
| New task, no prior context needed | ✅ | ❌ | ❌ |
| Resuming interrupted work | ✅ | ✅ | ❌ |
| Debugging a recurring issue | ✅ | ✅ | ❌ |
| Implementing against a spec/ADR | ✅ | ❌ | ✅ |
| Onboarding to unfamiliar subsystem | ✅ | ❌ | ✅ |
| Post-incident review | ✅ | ✅ | ✅ |
Spawn Template Pattern
The default spawn prompt should include Hot tier only:
## Memory Context
### Hot (current session)
{hot_context}
Add --include-cold when the task needs history:
```
Memory Context
Hot (current session)
{hot_context}
Cold (summarized history — load on demand)
See: .squad/memory/cold/{agent-name}.md ```
Add --include-wiki when the task needs domain knowledge:
```
Memory Context
Hot (current session)
{hot_context}
Wiki (durable reference)
See: .squad/memory/wiki/{topic}.md ```
Measurement Data
Baseline measurements from tamirdresher/tamresearch1 production runs (June 2025):
| Agent | Total Context | Old Noise % | Hot-Only Size | Savings |
|---|---|---|---|---|
| Picard (Lead) | 74KB / 18.5K tokens | 96% | ~3KB | 55% |
| Scribe | 52KB / 13K tokens | 91% | ~4KB | 48% |
| Data | 43KB / 10.7K tokens | 88% | ~3.5KB | 42% |
| Ralph | 38KB / 9.5K tokens | 85% | ~3KB | 38% |
| Worf | 34KB / 8.5K tokens | 82% | ~3KB | 20% |
Average savings: 20–55% per spawn with Hot-only loading. Cold + Wiki on-demand adds ~2–8KB when needed, still well below current baselines.
Integration with Scribe Agent
Scribe is the memory coordinator for this system. It automates tier promotion:
- End of session: Scribe compresses Hot → Cold summary (keeps ~10% of session verbosity)
- After 30 days: Scribe promotes Cold → Wiki for decisions/facts that aged into stable knowledge
- On-demand wiki writes: Any agent can request Scribe to write a wiki entry mid-session using
scribe:wiki-write
See Scribe charter: .squad/agents/scribe/charter.md
Implementation Checklist
- Scribe writes Hot context file at session start (
.squad/memory/hot/{agent}.md) - Scribe compresses and writes Cold summary at session end
- Spawn templates default to Hot-only
- Coordinators add
--include-cold/--include-wikiflags as needed - Wiki entries stored in
.squad/memory/wiki/ - Cold entries stored in
.squad/memory/cold/with 30-day TTL
References
- Upstream issue: bradygaster/squad#600
- Production data: tamirdresher/tamresearch1 (June 2025)
Spawn Template
Spawn Template: Agent with Tiered Memory
Use this template when spawning any Squad agent. By default it loads Hot tier only. Add optional sections as needed.
Task
{task_description}
WHY
{why_this_matters}
Success Criteria
- {criterion_1}
- {criterion_2}
Memory Context
🔥 Hot (always included)
Paste current session context here (2–4KB max):
Current task: {task_description}
Active decisions: {decisions_this_session}
Last actions: {last_3_to_5_actions}
Blockers: {current_blockers_or_none}
Talking to: {current_interlocutor}
❄️ Cold (include when task needs history — add --include-cold)
Load on demand. Do not inline unless specifically needed.
Summarized cross-session history is at:
.squad/memory/cold/{agent-name}.md
Include when:
- Resuming interrupted work
- Debugging a recurring issue
- "What have we tried before?"
To load cold memory, add this section and fetch the file before spawning:
## Cold Memory Summary
{contents_of_.squad/memory/cold/{agent-name}.md}
📚 Wiki (include when task needs domain knowledge — add --include-wiki)
Load on demand. Reference specific wiki docs by path.
Wiki entries are at: .squad/memory/wiki/
Include when: - Implementing against an ADR or spec - Onboarding to unfamiliar subsystem - Need stable conventions or API contracts
To load wiki, add this section and reference the specific doc:
## Wiki Reference
{contents_of_.squad/memory/wiki/{topic}.md}
Escalation
If blocked or uncertain:
- Architecture questions → @picard
- Security concerns → @worf
- Infrastructure/deployment → @belanna
- Memory/history questions → @scribe
Notes
- Hot tier is always included and should stay under 4KB
- Cold adds ~8–12KB; only include when history is relevant
- Wiki adds variable size; only include specific relevant docs
- See
skills/tiered-memory/SKILL.mdfor full tier reference - See
docs/tiered-memory-guide.mdfor wiring instructions