Retrospective

Retrospective Analysis

Re-examine earlier documents and decisions through the lens of a new result (theorem, proof, milestone, gap closure, or significant discovery). Produces standardized retrospective reports.

When to Use

• A major result has been established and you want to trace its implications through earlier work
• A milestone occurred and you need to reassess claims that depended on it
• A gap closure happened and previously speculative claims may now be provable or falsifiable
• The user says "run retrospective agents" or "re-examine early work through X lens"

How to Invoke

Launch one subagent per domain using the Task tool or dispatch-agent skill with run_in_background: true. Run them in parallel.

Prompt Template

You are a retrospective analyst.

**New Result:** {statement of the new result}
**Date:** {date}
**Reference:** {path to proof/document}

Re-examine the following documents through this lens:
1. {path1}
2. {path2}
...

For each document, assess:
- What was claimed and at what confidence level?
- Does the new result change the status of any claims?
- Which claims are now provable or falsifiable that were not before?
- Are there early intuitions that turned out to be correct?

**Write your report to:**
  {output_directory}/{date}-{domain-slug}-retrospective.md

Use the standard report format below.

Output Location

Place reports in a designated retrospective directory: {output_directory}/{date}-{domain-slug}-retrospective.md

• {date} = ISO date of triggering result (e.g., 2026-03-11)
• {domain-slug} = kebab-case domain name (e.g., backend-api, auth-system, data-pipeline)

Report Format

Frontmatter

---
created: "{date}"
type: retrospective
trigger: "{name of triggering result}"
scope: "{comma-separated keywords}"
documents_reviewed:
  - {relative path to each document}
---

Body Structure

# Retrospective: {Domain Title}

## The Shift
One paragraph: the single biggest change the new result introduces for this domain.

## Document-by-Document

### 1. {Document Title} ({Date})
**Claimed:** What was the original claim?
**Then:** What confidence level at the time?
**Now:** What changes with the new result?
**Verdict:** Promoted / Corrected / Unchanged -- then explanation.

(repeat for each document)

## Cross-Cutting Findings

### Promoted (speculation -> confirmed)
| Claim | Before | After | Mechanism |
|-------|--------|-------|-----------|

### Corrected (right intuition, wrong mechanism)
List of claims where the conclusion was right but the route was wrong.

### Unchanged
Claims unaffected by the new result.

### Early Intuitions Validated
Numbered list of insights that turned out correct before justification existed.

## Open Problems
Numbered list of concrete, testable questions opened or sharpened by the new result.

Guidelines

1. Be honest about confidence levels. Use a consistent scale. Do not inflate.
2. Distinguish mechanism from conclusion. Right conclusion via wrong mechanism -- note both.
3. Quote early documents directly when claims are now validated or corrected.
4. Separate coincidences from structural identities. The new result may promote some and demote others.
5. Flag cross-domain connections prominently when the same pattern appears in multiple areas.
6. The new result is the lens, not the conclusion. Re-evaluate OLD work; do not extend the new result.

Example Invocation

After completing a major refactor or proving a key result, launch domain-specific retrospective agents:

Task(description="Retrospective: API layer",       domain="api-layer")
Task(description="Retrospective: Auth system",      domain="auth-system")
Task(description="Retrospective: Data pipeline",    domain="data-pipeline")
Task(description="Retrospective: Client SDK",       domain="client-sdk")

Each produces a report at {output_directory}/{date}-{domain}-retrospective.md.

Confidence Scale

Use a consistent scale for before/after assessments:

Anti-Patterns

• Retroactive rationalization -- Do not rewrite history to make past decisions look better. Report what was actually claimed and believed.
• Scope inflation -- The retrospective is about re-evaluating old work, not extending the new result into new territory.
• Missing the tensions -- Disagreements between old claims and new results are the most valuable findings. Do not smooth them over.
• Skipping open problems -- Every good retrospective should surface new questions, not just validate old answers.