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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds real behavioral value beyond that: the result is a signed document, each signal carries its source, and absent signals appear as «none» rather than being omitted — a return-shape detail an agent cannot get from structured fields.

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?

One front-loaded sentence that leads with the key framing ('everything the hub knows ... as one signed document') before enumerating signals. The long em-dash list is dense but every item is informative; minimal waste.

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?

With no output schema, the description bears the full burden of explaining return content, and it does so by enumerating the signal categories and noting source attribution and «none» placeholders. Coverage of parameter semantics and usage routing is 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 0% for the single required agentId, so the description carries the burden. It only implies the parameter is an agent identifier ('about an agent') and says nothing about ID format, accepted values, or what happens with an unknown agent.

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 resource and scope: a single signed composite document aggregating every trust signal the hub holds about an agent. This is clearly broader than siblings like agent_liveness or get_agent, though the description never names those siblings to make the boundary explicit.

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?

No when-to-use guidance and no alternatives named. The agent must infer from 'everything the hub knows' that this is the holistic trust lookup, but nothing states when to prefer it over agent_liveness, get_agent, or search_agents.

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