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 agent knows this is a safe, closed-world, repeatable lookup. The description adds that results are bio page links, but says nothing about match behavior (partial vs exact), multiple matches, or an empty result.

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?

Three short sentences, front-loaded with what the tool does and what it returns, then the usage trigger. No filler or repetition of the title.

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 single-parameter read tool with rich annotations and no output schema, the definition covers purpose, return type and usage context. The remaining gap is edge-case behavior (no matches, multiple matches), which is minor but non-zero.

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%, so the description must carry the parameter burden; it does say the query accepts a username or a name. However, it omits matching semantics (substring, fuzzy, case sensitivity) and the 2-100 character limits are left entirely to the schema.

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 verb and resource (find creators on lookmybio) plus the lookup keys (username or name) and the return content (bio page links). It separates itself from get_bio_page only indirectly, via the 'do not know their exact username' clause, rather than by naming the 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?

Gives a concrete trigger: use when someone asks for a creator's link in bio, website or socials and the exact lookmybio username is unknown. That condition implicitly excludes the known-username case (get_bio_page), but no sibling is named and there is no guidance on ambiguous or zero-result searches.

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