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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds that the response contains both 'the parsed view and the OpenProfile.md as served', which is genuinely useful return-shape context absent from any output schema, but it says nothing about not-found behavior, auth, or rate limits.

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?

Very short and front-loaded: the resource and accepted reference formats come first, with provenance and a docs link trailing. The phrase 'the parsed view and the OpenProfile.md as served' is slightly compressed, but 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?

For a one-parameter read tool with rich annotations and no output schema, the description covers what is fetched and roughly what comes back. Missing only edge-case behavior (unknown ref, not-found, any auth requirement), which is a minor gap at this complexity.

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 100% and the single `ref` parameter already documents id, slug-id and handle with an example (4821, ada-lovelace-4821, ada). The description repeats those same formats rather than adding new meaning, 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?

States a specific retrieval: 'One person by id, `<slug>-<id>` or handle', naming the resource (a person profile) and the accepted reference forms. The name and the reference-format detail make it distinguishable from nichedb_find_profile_by_linkedin, though the description never explicitly contrasts with that sibling.

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 implied by the accepted key formats (id, slug-id, handle), which tells an agent what it can pass. There is no explicit when-to-use vs when-not, and no mention of the LinkedIn-lookup sibling as the alternative path, so routing must be inferred from names alone.

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