firstmate: Hook for Claude Code

.claude/settings.json

SessionStart is a hook for Claude Code from kunchenguid/firstmate. Its token cost is not measured, scanned A, original, MIT.

A session-start hook that runs the fm-sessionstart-run.sh script when a coding session begins.

In plain words
What is it for?
Use it to run the Firstmate session-start routine, provided the project path and hook conditions are available.
Why use it?
It automates a startup action so the script does not have to be launched manually at the beginning of each session.

Hook for Claude Code

Written for Claude Code: $CLAUDE_PROJECT_DIR variable.

This is kunchenguid/firstmate's own configuration. It tells Claude Code how to work on firstmate itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything firstmate configures →

One of 5 entries in settings.json upstream. Installing this one merges just its entry into your config; the other 4 are separate, each on its own page.

About the project

firstmate is an agent distribution that lets one coding agent coordinate a crew of autonomous agents working in separate git worktrees. It is for running parallel fixes, investigations, plans, and audits while receiving completed pull requests, merges, or reports through one supervising agent. The catalogue entries provide skills, hooks, instructions, and settings for operating this workflow.

kunchenguid/firstmate · 8,295 stars · on GitHub

Reuse

Borrowing it

Nothing to install: this file belongs to kunchenguid/firstmate. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/kunchenguid/firstmate/main/.claude/settings.json
Clone the repo
git clone --depth 1 https://github.com/kunchenguid/firstmate

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 SessionStart

README.md
[![agentmods](https://agentmods.dev/badge/hooks/kunchenguid/firstmate/session-start/github.svg)](https://agentmods.dev/hooks/kunchenguid/firstmate/session-start)
Your own site
<a href="https://agentmods.dev/hooks/kunchenguid/firstmate/session-start"><img src="https://agentmods.dev/badge/hooks/kunchenguid/firstmate/session-start/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for SessionStart

Your own site · 80×15
<a href="https://agentmods.dev/hooks/kunchenguid/firstmate/session-start"><img src="https://agentmods.dev/badge/hooks/kunchenguid/firstmate/session-start.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session not measured What this adds to a session before it is invoked.
When invoked not measured Not applicable: nothing here is loaded into a session.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Security

Grade A, and why

SessionStart 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 1mo ago.

A static scan of the commands this hook runs, not an audit. A hook is shell that executes on your machine at the event it names, which is why every command in it is printed with what was found.

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/settings.json · 13 lines

What it actually says

{
  "SessionStart": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "[ -z \"${GROK_AGENT:-}${GROK_HOOK_EVENT:-}\" ] || exit 0; exec \"$CLAUDE_PROJECT_DIR\"/bin/fm-sessionstart-run.sh",
          "timeout": 180
        }
      ]
    }
  ]
}
Same file

What else settings.json configures

This page is one entry in a file that holds 5. Installing the file brings all of them; each is measured and scanned on its own page.

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. 1mo ago First seen · 13 lines scan A 06a30b71c637

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository kunchenguid/firstmate (8,295 stars, last pushed today), licensed MIT. Its token cost is not measured: a hook is shell that never enters the context. 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 2026-08-30.