add-slack

add-slack is a skill for Claude Code from nanocoai/nanoclaw. It costs 12 tokens per session (3,209 once invoked), scanned B, original, MIT.

A Slack connection for chatting with the coding agent through direct messages and channels. Slack is a workplace messaging service; this add-on covers the basic one-bot experience.

In plain words
What is it for?
Use it to receive and send agent messages in Slack DMs and channels. Features for child bots, shared rooms, canvases, and DM onboarding are provided separately.
Why use it?
It lets people interact with the agent where their team already communicates. It also supplies the channel adapter, bot safeguards, setup logic, and related tests.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: reads .claude/ paths.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is bash setup/lib/restart.sh.

Good fit Use it to receive and send agent messages in Slack DMs and channels. Features for child bots, shared rooms, canvases, and DM onboarding are provided separately.

Compare 6 skills from other repositories ↓
About the project

NanoClaw is an AI assistant that runs agents inside separate Linux containers, isolating their files and execution environments. People use it to connect agents to messaging services and run assistants with memory and scheduled jobs. The catalogue contains skills and instructions for extending or operating NanoClaw.

nanocoai/nanoclaw · 30,727 stars · on GitHub · nanoclaw.dev

Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/nanocoai/nanoclaw
agentmods
npx agentmods add skills/nanocoai/nanoclaw/add-slack

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 add-slack

README.md
[![agentmods](https://agentmods.dev/badge/skills/nanocoai/nanoclaw/add-slack/github.svg)](https://agentmods.dev/skills/nanocoai/nanoclaw/add-slack)
Your own site
<a href="https://agentmods.dev/skills/nanocoai/nanoclaw/add-slack"><img src="https://agentmods.dev/badge/skills/nanocoai/nanoclaw/add-slack/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 add-slack

Your own site · 80×15
<a href="https://agentmods.dev/skills/nanocoai/nanoclaw/add-slack"><img src="https://agentmods.dev/badge/skills/nanocoai/nanoclaw/add-slack.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 12 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,209 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 2 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 3 findings, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Rogue Agent · line 29
    Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.
    Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
  • medium Agent Snooping · line 42
    Skill enumerates or reads other installed skills. Access to other skills' SKILL.md files or the skills directory reveals prompt instructions, capabilities, and secrets that should be invisible to peer skills.
    Fix: Remove all code or instructions that list or read other skills' files or directories. Skills should operate independently; cross-skill access is a privilege escalation.
  • medium Data Exfiltration · line 175
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
How audits are shown
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 5.1 $0.00012 $0.03209
Opus 5 $0.00006 $0.01605
Sonnet 5 $0.00002 $0.00642
Haiku 4.5 $0.00001 $0.00321

Measured 7d ago against content hash b44a6b8c0850, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade B, and why

add-slack scanned grade B with 2 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 7d 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.

Sends data to an external URLmediumData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

curl -s -X POST https://slack.com/api/conversations.open -H "Authorization: Bearer {{bot_token}}" -H "Content-Type: application/json" -d '{"users":"{{owner_handle}}"}' | jq -er '"slack:" + .channel.id'

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -sf -X POST https://slack.com/api/auth.test -H "Authorization: Bearer {{bot_token}}" | jq -er '"@" + .user + " in " + .team'
.claude/skills/add-slack/SKILL.md · 212 lines

How it starts

The opening of the file, as written. The whole thing — 212 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Add Slack Channel

Adds Slack support via the Chat SDK bridge. Trunk ships no channels — this skill copies the Slack channel layer (adapter, shared lib, bot-inbound guard, provisioning core, container skills) in from the channels branch. The Apply steps carry nc: directive fences (an agent applies the prose, a parser the directives); all idempotent.

This is the base Slack experience: one bot, DM and channel chat. The Slack agents feature — child bots provisioned from create_agent, shared rooms, canvases, DM onboarding — ships separately in /slack-a2a-rooms + /slack-agent-flow, in-tree under .claude/skills/ (their canonical home; the channels branch keeps a compatibility copy for older checkouts). The setup wizard applies them automatically, and they can be applied on top of this install at any time. Existing classic installs that want the Slack agents experience should use /migrate-slack-agents rather than re-running this skill (classic keeps working; that migration is optional).

Apply

1. Copy the channel payload

Fetch the channels branch and copy the payload into place (overwrite — the branch is canonical):

src/channels/slack.ts
src/channels/slack-lib.ts
src/channels/slack-lib.test.ts
src/channels/slack-a2a-guard.ts
src/channels/slack-a2a-guard.test.ts
src/channels/slack-raw-text.ts
src/channels/slack-raw-text.test.ts
src/channels/slack-registration.test.ts
src/channels/slack-instances-registration.test.ts
src/provisioning/slack-app.ts
src/provisioning/slack-app.test.ts
container/skills/slack-formatting/SKILL.md
  • Adapter + shared lib (slack.ts, slack-lib.ts): bridge registration, wiring defaults, conversation resolver, the native SLACK_INSTANCES loop — pinned by the two registration tests.
  • Bot-inbound guard (slack-a2a-guard.ts): drops bot-authored inbound at the bridge by default; feature skills register a narrower admission policy on its seam.
  • Raw-text recovery (slack-raw-text.ts): recovers pasted tables, which Slack delivers as attachment blocks in message.raw rather than as text — slack.ts imports it directly, so it travels with the adapter.
  • Provisioning core (src/provisioning/slack-app.ts): manifest template, scope/event constants, and the broker + manager-token transports for creating a Slack app programmatically. Nothing on the adapter path imports it — the setup wizard's auto-provision pre-step and feature skills do.
  • Container skills: slack-formatting/ (mrkdwn syntax; synced to ~/.claude/skills).

Read the full file on GitHub · 212 lines

Files

What ships with it

2 files 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. 7d ago Changed · +2 lines b44a6b8c0850
  2. 10d ago First seen · 210 lines · 12 tokens per session scan B 99707f2c262d

Subscribe to this mod's changes

add-slack is a skill published in the GitHub repository nanocoai/nanoclaw (30,727 stars, last pushed today), licensed MIT. It adds 12 tokens to every session and 3,209 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

Pynchy Ops

Use when managing the pynchy service on the server — deploying changes, observing logs, checking service status, restarting the service, setting up GitHub auth, rebuilding the agent container, or running commands on the live Pynchy host. Also use when interacting with the LiteLLM proxy — investigating failed requests…

crypdick/pynchy · 110 tokens

webhook-subscriptions

Create and manage webhook subscriptions for event-driven agent activation. Use when the user wants external services (GitHub, GitLab, Stripe, Linear, PagerDuty, Sentry, or any generic source) to trigger agent runs by POSTing events to a URL.

moltis-org/moltis · 57 tokens

Pynchy Development

Use when running pynchy locally — running the app, tests, linting, formatting, prek hooks, or rebuilding the agent container. Also use when determining whether you're on the live Pynchy host or a local machine, and for debugging agent behavior-- session transcript branching, inspecting message history and agent traces…

crypdick/pynchy · 79 tokens

Pynchy Plugin Authoring

Use when creating, scaffolding, or updating a pynchy plugin, including channels, MCP servers, skills, agent cores, workspace specs, and container runtime plugins. Also use when users ask how to register plugins via config.toml, add entry points, or validate plugin hook wiring.

crypdick/pynchy · 64 tokens

x-integration

Post tweets, like, reply, retweet, and quote on X (Twitter) using browser automation. Use when the user asks you to interact with X/Twitter.

crypdick/pynchy · 38 tokens

slack-token-extractor

Refresh expired Slack browser tokens (xoxc/xoxd) using persistent browser sessions. Use when Slack MCP tools fail with authentication errors.

crypdick/pynchy · 34 tokens