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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so safety is covered. The description adds worthwhile behavior — that the result set is restricted to owner-opted-in discoverable spaces and what fields come back — but says nothing about pagination, result limits, or ordering, which matters for a browse/list tool.

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 compact sentence with no filler, and the scoping constraint (owner-discoverable) is front-loaded ahead of the field list. It is telegraphic to the point of omitting a verb, 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?

For a one-parameter, annotation-covered read tool, the return fields and access scope are stated, which is most of what an agent needs. However, with an output schema absent and the `q` parameter undocumented, the definition leaves real gaps about how to drive the query and what the response volume looks like.

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% and the single parameter `q` is never mentioned in the description. Whether `q` is a full-text search, a prefix filter, or a name substring match is left entirely to inference, so the description fails to compensate for the schema 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 identifies the resource (spaces) and a clear scope qualifier — only spaces whose owners marked them discoverable — plus the fields returned (id, name, kind, about, member count). That implicitly separates it from spaces_mine, though it never names the sibling or uses an explicit verb like 'list' or 'browse'.

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 when-to-use / when-not-to-use guidance and no alternative named. An agent must infer from the phrase 'owners made them discoverable' that this is the public-directory counterpart to spaces_mine, and nothing tells it how this differs from directory_search or other discovery tools in the sibling list.

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