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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description still adds real behavioral context beyond that: results are limited to opted-in discoverable subjects, meaning a null result carries no negative implication — an important interpretive trait annotations cannot express. It omits pagination/limit behavior and result shape, which keeps it from 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?

Two sentences with no filler, and the most important framing ('resolver, not a directory') plus the critical caveat ('absence is never a finding') are both front-loaded. Every clause earns its place.

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 simple four-parameter resolver with rich annotations and full schema coverage, the description covers purpose, precondition, and the key result-interpretation caveat. With no output schema, a brief hint about what a match record contains would have closed the remaining gap.

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 100%, so all four parameters (q, limit, cert_level, jurisdiction) are already documented in the schema. The description reinforces the meaning of 'q' as a name you already hold but adds no interpretation for limit, cert_level, or jurisdiction, so the baseline 3 applies.

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 gives a specific verb and resource ('Confirm a subject') and explicitly frames the tool as 'a resolver, not a directory,' which tells an agent how it differs from broad search-style siblings. It stops short of naming any concrete alternative, so the differentiation stays conceptual rather than operational.

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?

'Confirm a subject you already hold a name for' communicates the precondition for use: this is for resolving a known name, not for browsing. The additional caveat that 'absence is never a finding' is genuinely useful usage guidance, though no explicit alternative tool is offered when the subject isn't found.

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