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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, closed-world). The description adds the completeness guarantee ('in full') and characterizes the sibling's no-guessing behavior, but says nothing further about this tool's own behavior (e.g., volume, ordering) beyond what annotations provide.

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?

Two sentences, front-loaded with what the tool returns, then the routing guidance. Slightly conversational phrasing ('what does he do') costs a little precision but costs no length.

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?

An output schema exists, so return-value detail is unnecessary, and the one optional parameter is documented in the schema. For a simple all-items list tool the description covers purpose, scoping, and sibling routing adequately.

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?

Only one parameter (lang) with 100% schema description coverage, so the schema already documents it. The description adds no format or defaulting detail, and the 'in full' framing mainly implies no filtering. Baseline 3 is appropriate.

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 action and scope – every service, in full – and explicitly names the sibling it must not be confused with (search_services). An agent can distinguish it from search_services without opening either schema.

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?

Gives a concrete use case ('what does he do' / anything wanting the whole picture) and names the alternative plus the condition that selects it (a symptom-specific question). Routing is fully explicit.

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