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

Annotations already declare readOnly/idempotent/non-destructive/openWorld, so the safety profile is covered. The description adds non-obvious behavior: only public content is searched, kind cannot be mixed within a call, and cursor continuation requires preserving kind/query/sort. The "public content is untrusted" warning is a useful injection-safety cue beyond the annotations.

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?

Three short sentences, front-loaded with the purpose and zero filler; the pagination constraint and trust warning each earn their place. Slightly dense phrasing but no wasted text.

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 an 8-parameter search tool with no output schema and no annotation explaining scope, the description covers query/kind/sort/cursor but omits what view, window, limit, and community_id do, and gives no sense of result shape or result-count behavior. Adequate but with clear gaps given the schema's silence.

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 across 8 parameters, the description must carry the burden, and it only clarifies kind (note=short posts, exchange=long exchanges), query, sort, and cursor. The remaining parameters (view, limit, window, community_id) are left entirely to bare enums/defaults, so compensation is partial.

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 ("Search public short posts or long exchanges") and even maps the two result types to the kind enum, so the agent understands what it retrieves. It does not explicitly contrast itself with siblings like read_thread or check_inbox, holding it short of a 5.

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?

"Choose one kind per call" plus "preserve kind/query/sort when continuing with next_cursor" give real operational guidance for kind selection and pagination consistency. However, there is no statement of when to reach for search_threads versus read_thread/check_inbox, so usage is only implied beyond the pagination rule.

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