Planning Preparation via Glean

Research enterprise context before entering plan mode by gathering design docs, similar implementations, stakeholders, and related systems.

When This Applies

Use plan prep when users:

• Want to research before entering plan mode
• Are planning architectural or strategic changes
• Need to understand related systems before designing
• Want to identify stakeholders and code owners early
• Ask: "plan with glean", "prep for plan", "research before planning"

Why This Matters

Better planning comes from enterprise context:

• Design Decisions: Understand what was tried before, why it worked or didn't
• Similar Implementations: Find proven patterns and learn from past approaches
• Stakeholders: Identify who needs to be involved or has relevant knowledge
• Related Systems: Understand dependencies and integration points

Local tools only see your current repo. This workflow searches your entire organization for existing decisions, patterns, and knowledge.

BE SKEPTICAL

Filter aggressively for relevant, current information.

Quality over quantity: 3-4 high-quality findings beat 10 weak ones.

Tool Selection

Workflow

Phase 1: Search for Design & Architecture

Find design documents, RFCs, and architectural decisions related to the task:

search "[task] architecture OR design doc"
search "[task] RFC OR proposal"
search "[task] pattern OR best practice"

Look for:

• Existing design decisions that apply
• Architectural patterns already in use
• Why past decisions were made
• Rejected approaches and lessons learned

Phase 2: Find Code Implementations & Patterns

Search for similar implementations across the codebase:

code_search "[task] implementation OR pattern"
code_search "[related systems] updated:past_month"

Look for:

• How other teams solved similar problems
• Existing code to learn from
• Patterns already in use
• Quality and maintenance level of examples

Phase 3: Identify Stakeholders & Owners

Find who's actively working on related systems:

code_search "[relevant systems] owner:* updated:past_month"
employee_search "[systems and names identified]"

Look for:

• Active code owners and maintainers
• People with recent commits in related areas
• Team leads and architects
• Documentation authors

Phase 4: Find Related Systems

Identify upstream and downstream dependencies:

code_search "[main system] calls OR depends OR imports"
code_search "[main system] updated:past_month"

Phase 5: Vet All Research

For each piece of research, apply the vetting criteria above. Reject stale, tangential, or low-quality content.

Phase 6: Generate Planning Context Report

Present vetted research findings organized by category:

# Planning Context: [Task]

## Design & Architecture
### Current Standards & Patterns
| Pattern | Description | Source | Updated |
|---------|-------------|--------|---------|
| [pattern] | [what it is and why] | [doc link] | [date] ✅ |

### Relevant Design Documents
| Document | Type | Key Takeaway | Updated |
|----------|------|--------------|---------|
| [Title] | RFC | [1-2 sentence summary] | [date] ✅ |

## Implementations & Patterns
### Recommended Examples
| Location | What It Does | Why It's Good | Status |
|----------|--------------|---------------|--------|
| [repo/path] | [brief description] | [Why recommend] | Active ✅ |

## Stakeholders & Ownership
### Active Owners
| Name | Role | Involvement | Contact |
|------|------|-------------|---------|
| [Name] | [Title] | [X] commits past month in [system] | [email] |

### Teams & Channels
- **Primary Team**: [team name]
- **Slack Channel**: [#channel] for questions

## Related Systems
- **Upstream** (depend on this): [systems]
- **Downstream** (this depends on): [systems]

## Key Insights
- [Important constraint or opportunity]
- [Proven pattern or anti-pattern]
- [Stakeholders who must be involved]

## Sources
| Document | Type | Relevance | Currency |
|----------|------|-----------|----------|
| [Title](URL) | RFC | [how it applies] | [date] ✅ |

If Limited Context Found

Don't pad with weak results:

# Planning Context: [Task]

## Limited Research Available

Found limited enterprise context for this task.

**What was searched:** Design docs, similar implementations, related systems
**Gaps:** No recent design docs, limited prior art

**Suggested next steps:**
1. Check with [suggested team] about prior attempts
2. Enter plan mode and design initial approach, then validate with stakeholders