[slack] Use readable profile names in drafts

plugins/slack/skills/slack-outgoing-message/SKILL.md

@@ -29,7 +29,8 @@ Read this reference **before finalizing any outgoing Slack text**:
 
 - Write concise Slack-ready text that follows the live tool contract plus `../slack/references/markdown.md`.
 - Prefer a short opener, a few tight bullets, and a clear ask or next step.
-- Use explicit Slack mention syntax only when you resolved the target successfully.
+- For drafts, use human-readable Slack profile names for people instead of raw user IDs or Slack mention syntax.
+- For direct sends, scheduled messages, and canvases, use explicit Slack mention syntax only when you resolved the target successfully.
 - Preserve source links, code, owners, dates, and commitments unless the user asked for edits.
 - Do not invent approvals, decisions, or follow-through.
 
@@ -60,7 +61,8 @@ Read this reference **before finalizing any outgoing Slack text**:
 
 ## Mention Rules
 
-- Resolve **user mentions** before writing when the message should tag a person, and use Slack mention syntax: `<@U123456>`.
+- For `slack_send_message_draft`, resolve each referenced person's Slack profile and write their human-readable profile name in the draft text, preferring `display_name` and falling back to `real_name` or the clearest available profile name. Do not put raw Slack user IDs or `<@U123456>` syntax in draft bodies unless the user explicitly asks for raw Slack mention markup.
+- For direct sends, scheduled messages, and canvases, resolve **user mentions** before writing when the message should tag a person, and use Slack mention syntax: `<@U123456>`.
 - Resolve **Slack user groups** before writing only when the runtime exposes a way to do so, and use Slack mention syntax: `<!subteam^S123456>`.
-- Do not rely on bare `@name` text in outgoing Slack messages.
+- Do not rely on bare `@name` text for actual sends, scheduled messages, or canvases.
 - If you cannot resolve the correct user or group, **tell the user** and compose the draft or message without implying the mention will work.

plugins/slack/skills/slack-outgoing-message/agents/openai.yaml

@@ -4,4 +4,4 @@ interface:
   icon_small: "./assets/slack-small.svg"
   icon_large: "./assets/slack.png"
   brand_color: "#611F69"
-  default_prompt: "Use $slack-outgoing-message to turn source context into final Slack-ready text for a draft, send, or canvas with correct Markdown and explicit Slack mentions."
+  default_prompt: "Use $slack-outgoing-message to turn source context into final Slack-ready text for a draft, send, or canvas with correct Markdown, readable draft names, and explicit Slack mentions when sending."

plugins/slack/skills/slack/references/markdown.md

@@ -4,9 +4,9 @@ Use this reference when writing Slack-ready text for these skills.
 
 ## Authoring Contract
 
-- Write clean Markdown-style text plus explicit Slack mention syntax.
+- Write clean Markdown-style text. Use explicit Slack mention syntax for actual sends, but use human-readable Slack profile names in draft bodies.
 - The active Slack runtime may convert Markdown into Slack mrkdwn or blocks before sending. Follow the live tool contract if it is more specific than this file.
-- Keep Slack-specific mention syntax for users and channels. Use user-group mention syntax only when the runtime can actually resolve the group.
+- Keep Slack-specific mention syntax for users and channels in direct sends, scheduled messages, and canvases. Use user-group mention syntax only when the runtime can actually resolve the group.
 
 ## Common Syntax
 
@@ -19,7 +19,8 @@ Use this reference when writing Slack-ready text for these skills.
 | Code block | `` ```text``` `` |
 | Quote | `> text` |
 | Link | `[label](https://example.com)` |
-| User mention | `<@U123456>` |
+| User mention in sends, scheduled messages, and canvases | `<@U123456>` |
+| User reference in drafts | Resolved human-readable profile name, such as `Jane Doe` |
 | Channel mention | `<#C123456>` |
 | User group mention | `<!subteam^S123456>` |
 | Bulleted list | `- item` |
@@ -29,5 +30,6 @@ Use this reference when writing Slack-ready text for these skills.
 
 - Prefer short paragraphs and `-` bullets for Slack posts.
 - Use heading-like standalone lines sparingly. Keep them short.
-- Do not rely on bare `@name` text for mentions.
+- Do not rely on bare `@name` text for mentions in actual sends, scheduled messages, or canvases.
+- In draft bodies, do not expose raw Slack user IDs such as `U123456`, `@U123456`, or `<@U123456>` unless the user explicitly asks for raw Slack mention markup.
 - Avoid `@here`, `@channel`, and similar broad notifications unless the user explicitly asked for them.