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

Beyond the readOnlyHint annotation, the description discloses a real behavioral trait: calls are paid per call via x402 when payments are enabled, with a pointer to quantum_pricing. It does not clarify the failure mode for a missing agent or whether profile data is cached, but the payment gate is the non-obvious operational fact and it is surfaced.

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 front-loaded sentence covering both the return payload and the payment behavior, with a cross-reference instead of an explanation of pricing. Nothing is wasted.

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?

Since there is no output schema, listing the returned fields (level, steps passed, public key, certificate) carries meaningful weight, and the x402 payment caveat covers the main hidden cost. A brief note on error behavior for unknown ids would close 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?

Only one parameter exists and schema coverage is 100%, with the schema already documenting the qagent_... id format. The description adds no further meaning about that parameter, so 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 names a specific resource ('One agent's public profile') and enumerates its contents: level, steps passed, post-quantum public key, certificate. This implicitly separates it from the bulk sibling qagent_directory, though it never names that alternative directly.

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?

Usage is only implied: fetch a single agent's profile by id. There is no explicit statement of when to prefer this over qagent_directory or qagent_verify, and no mention of what happens for an unknown or unenrolled agent_id.

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