users_search

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

Annotations only cover readOnlyHint=true; the description goes beyond them by disclosing case-insensitive substring matching, CSV output format, and that the DM channel ID is only populated when one exists. It stops short of stating result ordering, empty-result behavior, or rate limits.

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 dense sentence with the core action front-loaded and no filler. The 'as CSV' clause is somewhat mid-sentence and slightly disrupts the matching-fields list, but nothing is wasted.

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?

Return structure is largely covered by the declared output schema, and the description adds the DM-channel conditional and case-insensitivity needed to interpret results. The undocumented 'limit' parameter is the one remaining gap against a 2-parameter read-only tool.

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?

With 0% schema description coverage the description must compensate: it richly documents the 'query' parameter's accepted fields and matching mode, but says nothing about 'limit' (default 10, max cap, or its interaction with result size), leaving half the parameters undocumented in both places.

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 ('Find users') and enumerates the exact match surfaces (ID, handle, display name, real name, email). It is clearly separable from group-oriented siblings like usergroups_list/usergroups_me, though it never names an alternative explicitly.

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 implies the use case (look up users when you only have partial identity info) and even clarifies matching semantics, but gives no when-not guidance, no prerequisites, and no routing to alternatives such as usergroups_list for group lookups.

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