8 tools with complete schemas and descriptions. Naming follows verb_noun convention (list_, get_, post_, add_, reply_). Descriptions are adequate (50-150 chars) but lack actionable context for LLM selection. Parameters are typed and mostly described, but lack constraints (enums, ranges, patterns). No output schemas documented. Error handling absent, no recovery guidance or categorization. Missing idempotency hints for write operations. Pagination support present but inconsistent (cursor vs offset). No tool annotations (readOnlyHint/destructiveHint). Composition is sound, tools are single-responsibility and chainable.

• Add output schemas to all tools. Document the response structure, field types, and which fields are safe to chain into downstream tools. Example: slack_list_channels returns {channels: [{id, name, is_archived}], next_cursor?: string}.
• Add destructiveHint and readOnlyHint annotations to tool definitions. Mark slack_post_message, slack_reply_to_thread, slack_add_reaction as destructive so agents know they have side effects and should not retry blindly.
• Add numeric constraints to parameters: limit (min: 1, max: 200), default: 100. Add regex pattern for thread_ts: '^\d{10}\.\d{6}$'. Add enum for reaction (validate against Slack emoji list or accept any alphanumeric).
• Implement error handling with recovery guidance. Catch Slack API errors and return structured responses: {error: 'channel_not_found', message: 'Channel C123 does not exist or is archived.', suggestion: 'Try slack_list_channels to find available channels.'}.
• Enhance descriptions with context and dependencies. Example: 'Get detailed profile information for a specific user. Call slack_get_users first if you only have a username. Returns email, real_name, profile_picture, and timezone. Requires user:read scope.'