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

Annotations already declare readOnlyHint=true, so safety is covered; the description adds that only public ('công khai') agents are lookupable and that the result includes the current birth certificate and verification status. It does not disclose behavior for missing/invalid agents or rate limits, so the added context is useful but partial.

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?

A single well-formed sentence that front-loads the action, identifier formats, and return value with no redundant filler. Slightly dense but every clause carries information.

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 does state what is returned (birth certificate, verification status) and covers the sole parameter, which is adequate for a simple read tool. However, it omits error/not-found behavior and any hint about response shape or identifier normalization, leaving minor gaps.

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 0% and the single parameter 'agent' has no description in the schema, so the description carries the full burden. It does so by enumerating the accepted formats (agentId, DID, subdomain) and the 300-character limit is implied by the schema, making the parameter usable without guessing.

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 uses a specific verb ('Tra cứu' / look up) and names the resource ('agent công khai'), and it lists the three accepted identifier forms (agentId, DID, subdomain) plus what is returned. It is clear enough that an agent can distinguish this read lookup from siblings like check_subdomain or verify_certificate, though it doesn't explicitly contrast with them.

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?

The description implies lookup usage but gives no explicit guidance on when to choose this tool over check_subdomain, verify_certificate, or get_profile. There is no mention of alternatives, preconditions, or when-not-to-use cases.

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