pin

Pin — Session Decision Board

Persist decisions, questions, constraints, and corrections to a JSON file that survives context compaction. A companion hook injects the board into every tool call so the model never forgets.

Auto-Invoke Rules

After responding to any user message where a decision was made, a question was asked about a proposal, or a constraint was stated, IMMEDIATELY invoke /pin with the appropriate category. Do not ask permission — just pin it.

Examples of auto-invoke triggers:

• User: "yes go with bun" → respond normally, then /pin ✅ use bun
• User: "what about the latency impact?" → respond normally, then /pin ❓ split services — latency impact?
• User: "no skip auth for now" → respond normally, then /pin ❌ auth layer — skip for MVP
• User: "MVP only, max 3 files" → respond normally, then /pin 📌 MVP only, max 3 files
• User: "no I meant artisans not developers" → respond normally, then /pin 🔧 target = artisans, not developers

Do NOT pin:

• Casual conversation, greetings
• Implementation details (code changes, file edits)
• Things already pinned (check board first)

Commands

Command	Action
/pin ✅ <text>	Pin approved item
/pin ❓ <text>	Pin pending question
/pin ❌ <text>	Pin killed/rejected item
/pin 📌 <text>	Pin scope constraint
/pin 🔧 <text>	Pin correction
/pin show or /pin	Display current board
/pin rm <n>	Remove pin by number
/pin clear	Clear all pins
/pin clear triage	Clear ✅/❓ only, keep 📌/❌/🔧

State File

Path: /home/mat/dev/praxis/.session-logs/<slug>/pins.json

Derive slug from CWD:

GIT_ROOT=$(git rev-parse --show-toplevel 2>/dev/null)
REL_PATH="${PWD#$GIT_ROOT/}"
SLUG=$(echo "$REL_PATH" | tr '/' '-')
PINS_DIR="/home/mat/dev/praxis/.session-logs/$SLUG"
PINS_FILE="$PINS_DIR/pins.json"

Schema:

{
  "items": [
    {
      "id": 1,
      "type": "approved",
      "emoji": "✅",
      "content": "use bun everywhere",
      "detail": "",
      "ts": "2026-04-01T14:30:00Z"
    }
  ],
  "next_id": 2
}

Type mapping: ✅=approved, ❓=pending, ❌=killed, 📌=scope, 🔧=correction

Pin (/pin <emoji> <text>)

Parse the emoji prefix to determine type. Text after emoji is content. If text contains —, split into content and detail.

1. Derive PINS_FILE path (see State File above)
2. mkdir -p the directory
3. Read existing file or init {"items":[],"next_id":1}
4. Check if content already pinned (exact match on content field) → if so, respond ⚠️ Already pinned. and stop
5. Check limits: 5 items per type, 20 total. If category full, drop oldest item of that type.
6. Append new item with id=next_id, increment next_id
7. Write file
8. Respond: 📌 Pinned #N: <emoji> <content> — one line only, then resume prior work

Show (/pin show or /pin)

1. Read PINS_FILE
2. If file missing or items empty: 📋 Pin board is empty.
3. Display:

📋 Pin Board (5 items)
 1. ✅ use bun everywhere (minor: keep fallback for CI)
 2. ✅ split the PR into 2
 3. ❓ split services — latency impact?
 4. ❌ auth rewrite — out of MVP scope
 5. 📌 MVP only, max 3 files

Remove (/pin rm <n>)

If no number: ⚠️ Usage: /pin rm <number>

1. Read PINS_FILE, find item with id === n
2. If not found: ⚠️ Pin #N not found.
3. Remove item, write file
4. Respond: 🗑️ Pin #N removed.

Clear (/pin clear)

1. Reset file to {"items":[],"next_id":<keep current next_id>}
2. Respond: 🗑️ Pin board cleared.

Clear Triage (/pin clear triage)

1. Remove items where type is approved or pending
2. Keep items where type is killed, scope, or correction
3. Write file
4. Respond: 🗑️ Triage cleared. <N> pins remaining.

Limits

• 5 items per type, 20 total
• When a category is full, drop the oldest item of that type (lowest id)

Key Behaviors

• One-line responses only. Never add commentary about pin content.
• Resume immediately. After any pin command, pick up the prior conversation exactly where it left off.
• Store verbatim. No cleanup, no categorization, no reformulation of user's words.
• Stable numbering. Gaps stay after deletion. next_id always increments, never reuses.