catchup

catchup is a command for Claude Code from mmacpherson/tenforty. It costs 0 tokens per session (169 once invoked), scanned A, original, MIT.

A branch-change catch-up procedure for Claude Code that compares the current branch with main and chooses how much code to reload based on the size of the changes.

In plain words
What is it for?
Use it to inspect changed files, account for renames, summarize modifications, and choose full-file, test-name, or diff-based review.
Why use it?
It helps the coding agent recover context after branch changes without loading every file unnecessarily.

Command for Claude Code

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/mmacpherson/tenforty/catchup
Clone the repo
git clone --depth 1 https://github.com/mmacpherson/tenforty

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for catchup

README.md
[![agentmods](https://agentmods.dev/badge/commands/mmacpherson/tenforty/catchup.svg)](https://agentmods.dev/commands/mmacpherson/tenforty/catchup)
Your own site
<a href="https://agentmods.dev/commands/mmacpherson/tenforty/catchup"><img src="https://agentmods.dev/badge/commands/mmacpherson/tenforty/catchup.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 169 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found 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 $0.00000 $0.00169
Opus 5 $0.00000 $0.00084
Sonnet 5 $0.00000 $0.00034
Haiku 4.5 $0.00000 $0.00017

Measured 4d ago against content hash 3a7b9dd6e992, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

catchup 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 4d ago.

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.

.claude/commands/catchup.md · 16 lines

What it actually says

Refresh Claude Code's memory on branch changes.

  1. Run git diff --stat main...HEAD and git diff --name-status main...HEAD
  2. Parse output to detect renames (exclude from counts)
  3. Auto-select strategy:
    • Small (<10 files): Load all changed files
    • Medium (10-25 files): Load core full, list test names only
    • Large (>25 files): Use diffs for files >500 lines
  4. Execute:
    • Core files (src/tenforty/*.py): Read full
    • Test files: List test names only
    • Generated files (*.cpp, *.pyx): Show diff only
    • OTS source: Skip (too large)
  5. Read files in parallel
  6. Summarize changes by type
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. 4d ago First seen · 16 lines · 0 tokens per session scan A 3a7b9dd6e992

Subscribe to this mod's changes

catchup is a command published in the GitHub repository mmacpherson/tenforty (84 stars, last pushed 12d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 169 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-01.