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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior, so the safety profile is covered. The description adds genuine behavior beyond that: results are ranked best-match-first and the empty-input case enumerates every tool. It says nothing about result limits or pagination, which keeps it off a 5.

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?

Four short sentences, front-loaded with what the tool does and what it returns before the usage hint. Nothing is redundant given the description is the only place ranking and empty-input behavior are stated in prose.

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 discovery tool with an output schema and full annotation coverage, this covers purpose, inputs, ranking, return fields and the no-argument case. An agent has everything needed to decide to call it and to interpret the results.

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 coverage is 100% and the schema already explains that task, query and keyword are searched together and that omitting all lists everything. The description's 'task or keyword' phrasing actually omits 'query', so it adds no meaning beyond the schema and is marginally less complete than it.

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 and resource ('Search the tools on this server') and adds the matching mode ('by task or keyword in plain words'). It also names what comes back (name, title, one-line summary, input fields), so an agent knows exactly what this tool produces versus the sibling action tools.

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?

'Use it when you are not sure which tool here fits a task' gives a clear triggering condition, and 'With no words it lists every tool' covers the degenerate case. It does not state when *not* to use it or name an alternative, but no sibling here offers overlapping discovery functionality, so the gap is minor.

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