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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds mode-specific field requirements but says nothing about pagination, return shape, or rate limits, which leaves behavioral context thin given no output schema.

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?

A single front-loaded sentence with tight parentheticals covering all three modes. No filler; every clause carries routing information.

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?

For a read-only query tool with annotations covering safety and no output schema, the description supplies the mode selection logic and param requirements an agent needs. Missing only return-format/pagination detail, which is minor given the annotation coverage.

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%, so the description must carry the load and largely does: it names the enum values and maps each action to its required/optional params (matchId, query, take, before). It stops short of explaining formats like the ISO datetime for `before` or take's 1-200 bound, which the schema constrains but does not describe.

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?

States a specific verb+resource ("Query messages") and enumerates the three action modes, so the agent understands the tool's scope. It does not explicitly differentiate itself from sibling query tools like members_query, but the action list makes the domain clear.

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?

The description routes the agent across the three modes by stating the required and optional fields for each (list_conversations needs none, get_messages needs matchId, search needs query). It gives clear in-tool context but no guidance on when to pick this tool over sibling query tools.

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