checkpoint

A workflow command for saving named snapshots of a code project and checking them later. It uses Git, a version-control system, and records each checkpoint in a log.

In plain words
What is it for?
Create, verify, and list checkpoints for development work. Compare files, test results, code coverage, and build status with an earlier checkpoint.
Why use it?
It gives you a clear reference point before or during changes, so you can see what changed and whether tests, coverage, and the build became better or worse.

Command

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/zhmxiaowo/opencode-simple/checkpoint
Clone the repo
git clone --depth 1 https://github.com/zhmxiaowo/opencode-simple
Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 424 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 91% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00023 $0.00424
Opus 5 $0.00012 $0.00212
Sonnet 5 $0.00005 $0.00085
Haiku 4.5 $0.00002 $0.00042

Measured yesterday against content hash 347f318a489a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

checkpoint scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

91% identical to checkpoint — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.opencode/commands/checkpoint.md · 79 lines

What it actually says

Checkpoint Command

Create or verify a checkpoint in your workflow.

Usage

/checkpoint [create|verify|list] [name]

Create Checkpoint

When creating a checkpoint:

  1. Run /verify quick to ensure current state is clean
  2. Create a git stash or commit with checkpoint name
  3. Log checkpoint to .claude/checkpoints.log:
echo "$(date +%Y-%m-%d-%H:%M) | $CHECKPOINT_NAME | $(git rev-parse --short HEAD)" >> .claude/checkpoints.log
  1. Report checkpoint created

Verify Checkpoint

When verifying against a checkpoint:

  1. Read checkpoint from log

  2. Compare current state to checkpoint:

    • Files added since checkpoint
    • Files modified since checkpoint
    • Test pass rate now vs then
    • Coverage now vs then
  3. Report:

CHECKPOINT COMPARISON: $NAME
============================
Files changed: X
Tests: +Y passed / -Z failed
Coverage: +X% / -Y%
Build: [PASS/FAIL]

List Checkpoints

Show all checkpoints with:

  • Name
  • Timestamp
  • Git SHA
  • Status (current, behind, ahead)

Workflow

Typical checkpoint flow:

[Start] --> /checkpoint create "feature-start"
   |
[Implement] --> /checkpoint create "core-done"
   |
[Test] --> /checkpoint verify "core-done"
   |
[Refactor] --> /checkpoint create "refactor-done"
   |
[PR] --> /checkpoint verify "feature-start"

Arguments

$ARGUMENTS:

  • create <name> - Create named checkpoint
  • verify <name> - Verify against named checkpoint
  • list - Show all checkpoints
  • clear - Remove old checkpoints (keeps last 5)
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 79 lines · 23 tokens per session scan A 347f318a489a

Subscribe to this mod's changes

checkpoint is a command published in the GitHub repository zhmxiaowo/opencode-simple (2 stars, last pushed 5mo ago), licensed MIT. It adds 23 tokens to every session and 424 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 91% identical to checkpoint, differing in 4 lines, and is treated as a copy.