Retro

Retro — Generate Honest Session Retrospective

Analyze the current conversation candidly and save a structured retrospective to the Obsidian vault. The goal is honest reflection — not self-congratulation — so future sessions can improve.

Tools needed: Bash, Write, Read

Procedure

Follow these steps exactly. Do not skip steps or reorder them.

Step 1 — Read config

Run:

cd "$(git rev-parse --show-toplevel 2>/dev/null || pwd)"
python3 -c '
import sys, os
import glob; sys.path.insert(0, max(glob.glob(os.path.expanduser("~/.claude/plugins/cache/*/obsidian-brain/*/hooks")), default="hooks"))
from obsidian_utils import load_config
c = load_config()
if not c.get("vault_path"):
    print("ERROR: vault_path not configured", file=sys.stderr)
    sys.exit(1)
print("VAULT=" + c["vault_path"])
print("SESS=" + c.get("sessions_folder", "claude-sessions"))
print("INS=" + c.get("insights_folder", "claude-insights"))
'

Parse each output line as KEY=VALUE, splitting on the first =.

If the file does not exist or is invalid JSON, tell the user:

> Config not found. Please run /obsidian-setup first to configure your Obsidian vault.

Stop here if config is missing.

Step 2 — Validate vault access

Run:

test -d "$VAULT_PATH/$INSIGHTS_FOLDER" && test -w "$VAULT_PATH/$INSIGHTS_FOLDER" && echo "OK" || echo "FAIL"

If FAIL, tell the user:

> The insights folder $VAULT_PATH/$INSIGHTS_FOLDER does not exist or is not writable. Run /obsidian-setup to fix this.

Stop here if FAIL.

Step 3a — Discover full session evidence

The active conversation buffer only covers the post-compact half of long sessions. Before drafting the analysis, gather every artifact the active session has already written to the vault.

cd "$(git rev-parse --show-toplevel 2>/dev/null || pwd)"
mkdir -p "$HOME/.claude/obsidian-brain" && chmod 700 "$HOME/.claude/obsidian-brain"
_OB_BUNDLE="$HOME/.claude/obsidian-brain/retro-bundle-$$.json"
_OB_ERR="$HOME/.claude/obsidian-brain/retro-bundle-$$.err"
python3 -c '
import sys, os, json, glob
sys.path.insert(0, max(glob.glob(os.path.expanduser("~/.claude/plugins/cache/*/obsidian-brain/*/hooks")), default="hooks"))
from obsidian_utils import load_config, get_session_context, gather_session_evidence
c = load_config()
ctx = get_session_context(c["vault_path"], c.get("sessions_folder", "claude-sessions"))
bundle = gather_session_evidence(
    c["vault_path"],
    c.get("sessions_folder", "claude-sessions"),
    c.get("insights_folder", "claude-insights"),
    ctx["session_id"], ctx["project"],
)
bundle["_ctx"] = ctx
print(json.dumps(bundle))
' >"$_OB_BUNDLE" 2>"$_OB_ERR"
_OB_RC=$?
if [ $_OB_RC -ne 0 ]; then
  _OB_ERRMSG="$([ -f "$_OB_ERR" ] && head -c 500 "$_OB_ERR" || echo "")"
  _OB_RC="$_OB_RC" _OB_ERRMSG="$_OB_ERRMSG" python3 -c "
import os, json
rc = os.environ.get('_OB_RC', '?')
errmsg = os.environ.get('_OB_ERRMSG', '')
print(json.dumps({
  'session_id': 'unknown',
  'snapshots': [],
  'insights': [],
  'decisions': [],
  'error_fixes': [],
  'discovery_errors': [f'evidence helper crashed (exit={rc}): {errmsg[:500]}'],
  '_ctx': {'session_id': 'unknown', 'hash': 'unknown', 'project': 'unknown', 'session_note_name': 'unknown'},
}))
"
else
  cat "$_OB_BUNDLE"
fi
rm -f "$_OB_BUNDLE" "$_OB_ERR"

Parse the JSON output. The bundle has these fields: session_id, snapshots, insights, decisions, error_fixes, discovery_errors, and _ctx (the cached get_session_context() result reused by Step 5).

Empty-bundle fallback. If bundle["_ctx"]["session_id"] == "unknown" AND bundle["discovery_errors"] == [], print:

> Note: no prior-session evidence found — falling back to active-conversation-only retro.

…and proceed with Step 3 using only the active conversation buffer. Do not include the ## Evidence Consulted section in Step 4 in that case.

Helper crash / partial failure. If bundle["discovery_errors"] is non-empty, do not silently fall back to "no prior-session evidence found." Instead emit:

> ⚠️ Evidence discovery partially or fully failed. Some vault artifacts may be missing from this retro. See the discovery-errors warning surfaced in Step 6 for details.

Then proceed with whatever evidence was collected (possibly none).

Discovery errors. If bundle["discovery_errors"] is non-empty, remember the list — it will be surfaced after the preview in Step 6.

Step 3 — Analyze the session honestly

Review the full current conversation. Be candid, not defensive or self-congratulatory.

When the bundle from Step 3a is non-empty: treat its snapshot bodies and insight/decision/error-fix bodies as first-class evidence, not background context. Pre-compact arcs in snapshot files almost always contain more decision points and dead ends than the post-compact half — surface specific corrections and abandoned approaches from there. The "What Didn't Work" section in particular should reflect the relative duration and decision density of both halves; if the pre-compact half ran 6 hours and the post-compact half ran 90 minutes, the analysis should weight accordingly.

The "What Didn't Work" section is the MOST valuable part of this retrospective — invest the most analysis there.

Evaluate the session across these five dimensions:

1. What approaches worked? — Successful strategies, good tool choices, efficient workflows, moments where the approach was clearly right.
2. What didn't work? — Be specific: wrong assumptions that led to dead ends, approaches that were abandoned partway through, time wasted on the wrong path, tools that failed or were misused, misunderstandings of the user's intent, overcomplicated solutions when a simple one existed, factual errors or hallucinations Claude produced.
3. What did the user correct or redirect? — Any moment the user said "no, that's wrong" or steered the conversation back — these are especially valuable signals.
4. Key learnings — Non-obvious insights that would be genuinely useful in future sessions. Not generic advice; specific to what happened here.
5. Process improvements — Concrete and actionable changes. Not vague ("be more careful") but specific ("check existing tests before writing new ones", "ask for the schema before generating SQL").

Step 4 — Structure the retrospective

Draft the note body using this exact structure:

## Evidence Consulted
- Active conversation:  messages (post-compact buffer)
- Snapshots:  file(s)
  - [[]] (, )
  - [[]] (, )
- Insights:  file(s)
  - [[]] — 
- Decisions:  file(s)
  - [[]] — 
- Error-fixes:  file(s)
  - [[]] — 

## What Went Well
- 

## What Didn't Work
- 
- 
- 

## Key Learnings
- 

## Process Improvements
- [ ] 

Rules for ## Evidence Consulted:

• Omit any list line whose count is 0 (no Snapshots: 0 file(s) noise).
• Omit the entire ## Evidence Consulted section if the empty-bundle fallback fired in Step 3a.
• Wikilinks ([[stem]]) preserve Obsidian backlinks and round-trip through the FTS index.
• Active-conversation message count is approximate — the count visible to the model when /retro fires; an order-of-magnitude figure is fine.

Important: "What Didn't Work" should have MORE items than "What Went Well." If the session went smoothly with no obvious failures, still find at least one improvement opportunity — there is always something.

Step 5 — Derive session ID and backlinks

The Step 3a bundle already carries the cached session context as bundle["_ctx"]. Read these fields directly:

• SESSION_ID = bundle["_ctx"]["session_id"]
• HASH = bundle["_ctx"]["hash"]
• PROJECT = bundle["_ctx"]["project"]
• SESSION_NOTE = bundle["_ctx"]["session_note_name"]

Important: If SESSION_ID is unknown, use unknown for source_session and omit source_session_note entirely.

Step 6 — Show preview and ask for edits

Present the full note to the user including frontmatter:

---
type: claude-retro
date: YYYY-MM-DD
created_at: 
source_session: 
source_session_note: "[[]]"
project: 
tags:
  - claude/retro
  - claude/project/
---

# Session Retrospective:  ()

## Evidence Consulted
...

## What Went Well
...

## What Didn't Work
...

## Key Learnings
...

## Process Improvements
...

Where:

• YYYY-MM-DD is today's date
• `` is the current UTC timestamp at second precision. Get it via:

``bash python3 -c 'from datetime import datetime, timezone; print(datetime.now(timezone.utc).isoformat(timespec="seconds"))' ` Example: 2026-04-24T18:42:11+00:00`

• ` and ` are derived from Step 5
• `` is derived from the current working directory name (basename of the git repo root or cwd)
• The source_session_note field creates an Obsidian backlink from the retro to its source session

Ask the user:

> Preview above. Would you like to: > - save as-is > - edit content — tell me what to change > - cancel — discard this note

Wait for the user's response. Apply any requested edits and show the updated preview. Repeat until the user says save or cancel.

Discovery errors. If bundle["discovery_errors"] is non-empty, after the preview but before the save/edit/cancel prompt, emit:

> ⚠️ file(s) could not be read during evidence discovery: > - ``: > > The retro proceeds with the readable evidence.

Each bundle["discovery_errors"] entry has the form ": ". Split on the first : to separate ` from ` for the bullet rendering. This is informational only and does not block save.

If cancel, stop here.

Step 7 — Generate filename and write

Construct the filename:

1. Date: YYYY-MM-DD (today)
2. Slug: retro (fixed — no title slug needed for retrospectives)
3. Hash: 4-character hex hash from current timestamp:

• macOS: date +%s | md5 | cut -c1-4
• Linux: date +%s | md5sum | cut -c1-4

Final filename: YYYY-MM-DD-retro-.md

Example: 2026-04-05-retro-a3f2.md

Run:

mkdir -p "$VAULT_PATH/$INSIGHTS_FOLDER"

Then use the Write tool to write the full note (frontmatter + body) to:

$VAULT_PATH/$INSIGHTS_FOLDER/YYYY-MM-DD-retro-.md

Then set permissions:

chmod 644 "$VAULT_PATH/$INSIGHTS_FOLDER/YYYY-MM-DD-retro-.md"

Step 8 — Confirm

Print:

> Retrospective saved! > - File: $VAULT_PATH/$INSIGHTS_FOLDER/ > - Tags: claude/retro, claude/project/ > - Open in Obsidian to review and track process improvements over time.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: abhattacherjee
• Source: abhattacherjee/claude-code-skills
• License: MIT

Install and usage instructions live in the source repository linked above.