# Slack Channel Summarization

> Summarize activity from one Slack channel and return a concise recap, post-ready update, or summary doc.

- Skill: `concertonotes/slack-channel-summarization` (Agent Skill, multi-file: 4 files)
- Install (CLI): `npx skillmds@latest add concertonotes/slack-channel-summarization`
- Raw SKILL.md: https://api.skillmd.com/api/skills/concertonotes/slack-channel-summarization/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Research & Search
- Author: ConcertoNotes (https://skillmd.com/u/concertonotes)
- Updated: 2026-09-08
- Page: https://skillmd.com/skills/concertonotes/slack-channel-summarization

---


# Slack Channel Summarization

Use this skill to summarize activity from one Slack channel, using a requested time window when provided or the last 100 messages otherwise, and optionally deliver the result back into Slack.

## Related Skills

| Workflow | Skill |
| --- | --- |
| Draft, send, or rewrite the final Slack update | [../slack-outgoing-message/SKILL.md](../slack-outgoing-message/SKILL.md) |

## Start Here

- If the user did not name a channel, ask which channel to review.
- If the user provided a window, use it. For requests like "today" or "this week," resolve the user's timezone with `slack_read_user_profile`.
- If the user did not provide a window, default to the last `100` messages in the channel.

## Workflow

1. Resolve the named channel with `slack_search_channels`.
2. Collect the initial pass with `slack_read_channel` and `limit: 100`. If the user gave a window, set `oldest` and `latest`. If not, read the latest messages.
3. Read a thread using `slack_read_thread` when the parent message looks important to the summary, for example a decision, blocker, launch, incident, or open question. Default to the last `50` replies unless the request requires more.
4. Read the full `## Formatting Rules` section below.
5. Consolidate the channel activity into a short summary grouped by topic. The summary should include recurring conversations, key decisions or follow-ups, notable updates, and important threads.
6. Match the delivery format to the request:
   - short recap or brief: reply in chat or use `../slack-outgoing-message/SKILL.md` for a Slack message
   - summary doc or canvas: use `slack_create_canvas`
7. Delivery intent rules:
   - if the user explicitly asked to post or send the summary in Slack, write it directly
   - if the user explicitly asked for a draft or review-first flow, create a draft
   - if the user asked for a canvas or summary doc in Slack, treat that as an immediate write, not a draft
   - if the user did not ask for Slack delivery, return the summary in chat

## Formatting Rules

- For a concise Slack or chat summary, you MUST use exactly this structure unless the user explicitly requests a different format.
- If you use `../slack-outgoing-message/SKILL.md` to draft or send the final message, this output contract remains binding. The downstream skill does not relax or rename these sections.


```md
**Channel Summary - <channel>**
**Overview**
<1-2 sentence summary>

**Topic: <topic 1>**
- ...
- ...

**Topic: <topic 2>**
- ...
- ...

**Notes**
- <gaps, caveats, or sparse activity>
```

- Group the summary into 2–4 topics when possible.
- Keep each topic to 1–5 bullets.
- Use the overview to explain what the channel was focused on overall.
- Start each bullet with the main update. Add an owner or next step only when it is clear from the channel.
- Within each topic, capture decisions, action items, notable updates, and thread outcomes.
- Note if a thread is still open or unresolved instead of implying it concluded.
- Omit **Notes** when there are no caveats, gaps, or sparse-activity disclaimers to add.
- For a canvas, expand each topic into a short section and use `slack_create_canvas`. Do this only when the user explicitly asked for a canvas, doc, or Slack-hosted summary.