Session Completion Validation

VerifiedSafe

Validate that session state and progress are properly recorded before ending a coding session. Helps prevent losing work by checking active_context.yaml modifications, proof logs, and plan consistency. Run manually before closing a session or switching projects.

Sby Skills Guide Bot
ProductivityIntermediate
506/2/2026
Claude CodeCodex
#session-validation#progress-tracking#proof-capture#state-management

Recommended for

Our review

Validates session completion by checking that progress is recorded in active_context.yaml and proof exists in .proof/session_log.jsonl before ending work.

Strengths

  • Prevents loss of work by ensuring state is saved before termination
  • Provides a structured session summary with progress and issues
  • Identifies orphaned steps, stale pointers, and missing context
  • Replaces Claude Code's Stop hook for Codex CLI environments

Limitations

  • Must be invoked manually – no automatic trigger
  • Cannot block termination, only warns
  • Relies on specific file conventions (active_context.yaml and .proof/session_log.jsonl)
When to use it

At the end of any coding session when finishing work, closing Codex CLI, or switching projects.

When not to use it

For quick checks when detailed validation is unnecessary, or when the user needs to exit immediately without saving progress.

Security analysis

Safe
Quality score90/100

The skill only reads local state files and runs a safe ls command to check for proof file existence. No external network calls, no destructive operations, no obfuscated code, and no data exfiltration.

No concerns found

Examples

End-of-session validation
I'm done for today. Please run the session completion check and let me know if everything is saved properly.
Pre-close check
Before I close the CLI, validate my session to make sure all progress and proof are captured.

name: edge-done description: Validate session completion before ending work. Use when finishing a coding session to ensure state was saved and proof exists.

Session Completion Validation

This skill replaces the Stop hook from Claude Code. Run it before ending your session to validate that work was properly recorded.

When to Use

Call this skill when:

  • Finishing work for the session
  • Before closing Codex CLI
  • When switching to a different project
  • The user says "done", "finished", "that's all", "goodbye"

Instructions

1. Read Current State

Load active_context.yaml and check:

| Check | Requirement | Validation | |-------|-------------|------------| | State exists | active_context.yaml file present | File can be read | | Objective set | objective field has value | Not null or empty | | Plan exists | plan array has items | At least one step | | Progress made | At least one step completed OR in_progress | Status check |

2. Check for State Modification

Compare the current state against what was loaded at session start:

  • Were any steps advanced?
  • Were any steps marked completed?
  • Was any memory added?

If NO state modification occurred:

WARNING: No progress recorded this session
- No steps were completed
- No steps were advanced
- State is unchanged from session start

Did you forget to update active_context.yaml?

3. Check for Proof

Look for evidence of work in .proof/session_log.jsonl:

# Check if proof file exists and has entries
ls -la .proof/session_log.jsonl

| Condition | Status | |-----------|--------| | File exists with entries | Proof captured | | File missing or empty | No proof recorded |

If NO proof exists:

WARNING: No proof captured this session
- .proof/session_log.jsonl is missing or empty
- Run $edge-log to record what you did

4. Validate Plan Consistency

Check for orphaned or inconsistent states:

| Issue | Detection | Suggestion | |-------|-----------|------------| | Step marked in_progress but no current_step | Orphaned work | Mark complete or reset | | current_step points to completed step | Stale pointer | Advance current_step | | Blocked steps without notes | Missing context | Add blocking reason |

5. Generate Session Summary

Produce a summary of the session:

========================================
SESSION COMPLETION CHECK
========================================

Session: [session.id]
Objective: [objective]

Progress:
  Steps completed this session: [N]
  Current step: [current_step] - [description]
  Overall progress: [completed/total] steps

State Changes:
  - [List of what changed in active_context.yaml]

Proof Captured:
  - [N] log entries in .proof/session_log.jsonl
  - Last entry: [timestamp] - [action summary]

Validation:
  [x] State file modified
  [x] Proof file has entries
  [x] Plan is consistent
  [ ] Issue: [if any]

Status: READY TO END | NEEDS ATTENTION
========================================

6. Block or Allow

If all checks pass:

Session validation PASSED

You may end this session. Progress and proof are recorded.

Next session: Run $edge-context to reload state.

If checks fail:

Session validation FAILED

Issues that need attention:
1. [Issue 1]
2. [Issue 2]

Suggested actions:
- [How to fix issue 1]
- [How to fix issue 2]

Please resolve these before ending the session, or acknowledge:
"End anyway - I understand progress may be lost"

Comparison to Claude Code Stop Hook

| Claude Code (Hook) | Codex CLI (Skill) | |--------------------|-------------------| | Automatic - runs when session ends | Manual - user must invoke | | Blocks termination if checks fail | Warns but cannot block | | State hash comparison | Manual state review | | Proof file existence check | Same check, manual |

Quick Validation

For a fast check without full summary:

Quick Session Check:
- State modified: [yes/no]
- Proof exists: [yes/no]
- Ready to end: [yes/no]

Tips

  • Run early, run often: Check validation before committing to end
  • Log as you go: Use $edge-log after each major action
  • Update state promptly: Mark steps complete immediately after finishing

Integration with Other Skills

The $edge-step skill should automatically call $edge-log after completing each step, which means proof should accumulate naturally.

Recommended workflow:

  1. $edge-context - Load state at session start
  2. $edge-step (repeats) - Execute work
  3. $edge-done - Validate before ending

If Validation Fails

No state modification

# Add a note to active_context.yaml showing session activity
# Even if no steps completed, document what was investigated

No proof captured

# Create proof retroactively
mkdir -p .proof
echo '{"timestamp":"<now>","type":"session_summary","action":"<what you did>","outcome":"<result>"}' >> .proof/session_log.jsonl

Inconsistent plan state

# Fix in active_context.yaml
current_step: [correct value]
plan:
  - description: "..."
    status: [correct status]
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