slack_search_messages

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover read-only and open-world behavior, and the description adds real value on top: it names the exact scopes required (search:read, users:read) and notes that author names are cached, which warns of a degradation mode. Pagination is signposted via the total/page/pages return note, though rate limits and result-window limits are not mentioned.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight sentences that lead with the action and follow with operational constraints; minimal waste. Minor redundancy in restating the count 1-100 range that the schema already enforces via minimum/maximum.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need no prose, and auth is covered. But for an 11-parameter query tool with zero schema descriptions, the description leaves most filter semantics undefined, and it never explains how this differs from the sibling slack_search.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% across 11 parameters, so the description carries the full burden and largely fails it: only count is clarified (1-100), while has, from_user, in_channel, after, before, page, sort, and sort_dir are never explained or given expected formats. The generic "optional filters" phrase does not compensate for that gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb+resource ("Search visible messages") plus the query mechanism ("raw Slack query and optional filters") and return shape. It does not, however, differentiate itself from the sibling slack_search, leaving an agent to guess which search entry point to use.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no guidance on when to choose this over slack_search, slack_read_channel, or slack_read_thread, and no statement of preconditions beyond the auth scopes. The phrase "optional filters" implies they exist but never says when to apply them.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.