| name | slack |
| description | Routes Slack workspace tasks: search and read channels, threads, DMs, and canvases, then hand off composition. Trigger on Slack recap, triage, search, or post intent. Never finalize outbound mrkdwn here (slack-outgoing-message) and not for channel-create, message-edit, delete, or admin APIs. |
| version | 1.0.1 |
When to Use
Use this skill as the router for any Slack-related task. Activate it when the user mentions any of the following trigger keywords or intents:
- Read/search: "check Slack," "find the message in #channel," "what did they say in the thread," "search Slack for…"
- Summarize/recap: "summarize the #ops thread," "recap the channel," "daily digest"
- Draft/reply: "draft a reply," "write a Slack update," "rewrite this for Slack"
- Send/post: "post this in #general," "send a DM to…," "schedule a Slack message"
- Canvas: "create a canvas," "update the canvas"
- Triage: "what do I need to respond to," "triage my Slack notifications"
Read the relevant Slack context first, then hand off to the most specific Slack workflow listed under Related Skills.
Prerequisites
- A connected Slack workspace accessible through the Slack tool connector.
- The current Slack app surface supports: reading/searching channels, users, threads, and canvases; writing messages, drafts, scheduled messages, and canvases.
- Unsupported actions (creating channels, editing messages, deleting messages, admin actions) must be flagged immediately—do not attempt them.
- Windows host is primary. Use PowerShell for connector and tool calls.
Procedure
1. Confirm support and scope
- Before asking the user for details, confirm the requested action is supported by the current Slack app surface.
- If the action is unsupported, say so immediately and offer the closest supported path. Do not collect unnecessary details first.
- For broad analysis requests (workspace-wide conclusions, "what's happening across Slack"), fail fast if the connector cannot establish reliable coverage. Do not invent channel names or imply the user is in a channel. Ask for a candidate channel list, a narrower scope, or a question answerable from specific channels, threads, profiles, or search results.
2. Determine intent
3. Read Slack context
- Use
slack_read_*, slack_list_*, and slack_search_* tools to gather the needed context (channels, threads, users, canvases).
- Load
references/markdown.md (this skill folder) immediately before composing any outgoing Slack text. It covers emphasis, lists, links, quotes, mentions, and code.
- If the task will produce outgoing Slack text or perform a Slack write, switch to ../slack-outgoing-message/SKILL.md before finalizing, and reread that file's
## Formatting Rules section immediately before any send, draft, schedule, or canvas creation.
4. Handle DM routing
- When the same message targets multiple specific people, first search for an existing group DM with the right people. Prefer the group DM over duplicate one-to-one DMs.
- If no suitable group DM exists, do not silently fan out separate DMs. Ask the user whether they want individual DMs or prefer to create a group DM themselves (the connector cannot create group DMs).
5. Resolve write targets from fresh data
- Before acting on a relative message target ("last message," "latest reply," "above," "that message"), re-read the destination channel or thread and resolve the target from fresh results.
- Do not reuse earlier reads for reactions, replies, edits, or other writes.
- If multiple channels or threads share similar topics, identify the intended destination before drafting or posting.
6. Execute or draft
- For post-ready messages: keep them short enough to scan quickly unless the user explicitly asked for a long-form announcement.
- For drafts: use the
slack-outgoing-message skill and follow its formatting rules.
- Preserve exact channel names, thread context, links, code snippets, and owners from the source conversation unless the user asked for changes.
- Flag high-impact targets: @channel, @here, mass mentions, and customer-facing channels must be called out to the user before posting.
7. Format output
- Prefer a short opener, a few tight bullets, and a clear ask or next step.
- Distinguish clearly between a private summary for the user and a post-ready message for Slack.
- When summarizing a thread, lead with the latest status, then list blockers, decisions, and owners.
- When drafting a reply, match the tone of the channel and avoid over-formatting.
Tool Rate Limits
Slack tools have per-minute RPM quotas by bucket, not by individual tool:
| Bucket | Tools |
|---|
| Search | slack_search_* |
| Read | slack_read_*, slack_list_*, lookup-style tools |
| Send/Write | message, draft, schedule, canvas creation tools |
Backoff rules:
- If a Slack tool returns 429, do not retry immediately and do not switch to an equivalent tool in the same bucket.
- If the response includes
Retry-After or another explicit wait hint, follow it.
- Otherwise, wait ~30 seconds before calling that bucket again.
- If the same bucket returns another 429, wait ~1 minute, then ~2 minutes after the next 429, continuing with exponential backoff.
- A 429 in one bucket does not imply other buckets are exhausted. While waiting on one bucket, continue making useful progress with other buckets when safe.
- If the task cannot be completed without the exhausted bucket after reasonable backoff, explain the rate limit to the user and return the best partial result or next step.
Write Safety
- Never silently change channel names, thread context, links, code snippets, or owners from the source.
- Always re-read the destination before resolving relative targets ("last message," "that thread").
- Always flag @channel, @here, mass mentions, and customer-facing channels before posting.
- Never fan out DMs to multiple people without confirming the user's preference.
- Never claim support for creating channels, editing messages, deleting messages, or admin actions.
Pitfalls
- Inventing channel names or membership: Do not imply the user is in a channel or present workspace-wide conclusions as authoritative without verified data. Ask for a candidate list instead.
- Stale reads for writes: Reusing earlier read results for replies, reactions, or edits can target the wrong message. Always re-read fresh.
- Downgrading explicit sends to drafts: If the user said "send" or "post," do not silently switch to a draft. Respect the explicit write intent.
- Over-formatting replies: Match channel tone. Excessive bold, headers, or bullet lists in a casual channel feel wrong.
- Ignoring bucket rate limits: A 429 on
slack_search_* does not mean slack_read_* is also limited, but retrying the same bucket immediately will cascade failures.
- Missing the markdown reference: Forgetting to load
references/markdown.md before composing outgoing text leads to incorrect Slack formatting (e.g., wrong mention syntax, broken links).
- Confusing private summary with post-ready message: Always label which output is for the user's eyes only versus what is safe to paste into Slack.
Verification
After completing the task, verify:
- Support check: The action taken is within the supported surface (read, search, write message/draft/scheduled message/canvas). If unsupported, the user was told and offered an alternative.
- Target resolution: Any write target was resolved from fresh read results, not stale data.
- DM routing: If multiple recipients were involved, the user confirmed group DM vs. individual DMs before any fan-out.
- High-impact flags: @channel, @here, mass mentions, or customer-facing channels were flagged before posting.
- Formatting: Outgoing Slack text followed
references/markdown.md and the slack-outgoing-message skill's ## Formatting Rules.
- Rate-limit handling: No immediate retries on 429; backoff was applied per bucket.
- Output clarity: Private summaries are distinguishable from post-ready Slack messages.
Light fallback: If Slack messages are missing, tell the user that Slack access may be unavailable, the workspace may be disconnected, or the wrong channel/thread may be in scope. Ask them to reconnect or clarify the destination.
Related Skills
Examples
- "Summarize the incident thread in #ops and draft a calm update for leadership."
- "Turn these meeting notes into a short Slack post for the team channel."
- "Read the product launch thread and draft a reply that confirms the timeline."
- "Rewrite this long update so it lands well in Slack and still keeps the important links."
- "Search #engineering for messages about the deploy failure and tell me who owns the follow-up."
- "Post a brief heads-up in #general about tomorrow's maintenance window."
