contacts

contacts is a skill for Claude Code, Codex from jtsternberg/claude-plugins. It costs 99 tokens per session (1,396 once invoked), scanned A, original, MIT.

A local address book for an agent’s email contacts, including names, roles, addresses, and how each address was verified. It is used with AgentMail, an email service for AI agents.

In plain words
What is it for?
Add, find, list, update, and remove contacts by name, alias, or email address before sending agent mail.
Why use it?
It reduces the risk of sending mail to a remembered or incorrect address. It keeps personal contact details out of the code repository.

Skill for Claude CodeCodex

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the agentmail plugin — 5 skills, 2 hooks shipped together

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 skills/jtsternberg/claude-plugins/contacts
Any agent
npx skills add jtsternberg/claude-plugins --skill contacts
Clone the repo
git clone --depth 1 https://github.com/jtsternberg/claude-plugins

Made for: Claude Code, Codex.

Or install agentmail, the plugin that ships this one along with the rest of its 5 skills, 2 hooks.

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 contacts

README.md
[![agentmods](https://agentmods.dev/badge/skills/jtsternberg/claude-plugins/contacts.svg)](https://agentmods.dev/skills/jtsternberg/claude-plugins/contacts)
Your own site
<a href="https://agentmods.dev/skills/jtsternberg/claude-plugins/contacts"><img src="https://agentmods.dev/badge/skills/jtsternberg/claude-plugins/contacts.svg" alt="Measured on agentmods" height="20"></a>
Per session 99 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,396 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 $0.00099 $0.01396
Opus 5 $0.00049 $0.00698
Sonnet 5 $0.00020 $0.00279
Haiku 4.5 $0.00010 $0.00140

Measured 5d ago against content hash bc1c0e19b7e8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

contacts 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 5d 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.

plugins/agentmail/skills/contacts/SKILL.md · 111 lines

How it starts

The opening of the file, as written. The whole thing — 111 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Contacts

A local address book for agent mail: humans and other agents, with the address, the role, and — the part that matters — how the address was verified.

Why this is a local file

AgentMail has no contacts resource. Checked three ways: zero hits for contact across the 82 paths in docs.agentmail.to/openapi.json, no contacts page in the docs index, and no contacts resource in CLI 0.7.14.

The nearest native thing is Lists (lists, inboxes:lists) — send/receive/reply × allow/block ACLs whose entries are an address-or-domain plus an optional reason. No name, no role, no notes. And they are a security control: writing one changes what the inbox is allowed to talk to, so a "remove a contact" gesture would silently alter deliverability. Don't use them as an address book. If the user asks to block or allow a sender, that genuinely is Lists — a different job, covered in using-agentmail.

The store

${XDG_CONFIG_HOME:-$HOME/.config}/agentmail/contacts.json, mode 0600, beside the state.json this plugin already writes.

Never in the repository. It holds personal addresses, and anything under a git worktree is one git add -A from being published. The script derives its path from the environment and takes no path flag, so there is nothing to point somewhere else by mistake.

Running it

# Codex: substitute the installed plugin directory for this path.
PLUGIN_ROOT="${CLAUDE_PLUGIN_ROOT}"
bash "$PLUGIN_ROOT/scripts/agentmail-contacts.sh" list

Repeat that assignment in every block you run — Codex shells keep no state between blocks.

init                        create an empty store; never overwrites
list   [--format json|text]
get    <query> [--format json|text]
add    --name N --email E [--kind human|agent] [--role R] [--notes T]
                          [--alias A]... [--verified-from V]
update <query> [any add flag]
remove <query> --yes

Exit codes, so you can branch without reading prose: 0 ok · 3 no match · 4 conflict (duplicate address, ambiguous query, or init over an existing store — nothing is written) · 5 store present but unparseable · 6 no python3 · 64 usage.

Read the full file on GitHub · 111 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 5d ago First seen · 111 lines · 99 tokens per session scan A bc1c0e19b7e8

Subscribe to this mod's changes

contacts is a skill published in the GitHub repository jtsternberg/claude-plugins (5 stars, last pushed today), licensed MIT. It adds 99 tokens to every session and 1,396 once invoked, about $0.0005 per session on Opus 5. 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 2026-08-31.