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 safety profile is fully covered elsewhere. The description adds the useful notions of 'full' and 'sourced' profiles, but never explains what sourcing means, what fields come back, or what an unknown slug produces. With annotations doing the heavy lifting, this is adequate but thin.

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 with no filler: the verb, the result, the keying parameter, and an example are all delivered immediately. Nothing could be removed without losing 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?

For a one-parameter read-only lookup with rich annotations, the description covers purpose, keying, and an example format. The main residual gap is that no output schema exists and the description does not sketch the shape of a 'full sourced profile', which an agent might want before calling.

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?

There is a single parameter with 0% schema description coverage, so the description bears responsibility here. It does clarify that slug identifies a provider and supplies a concrete example format ('cobalt'), which is real added meaning, but it says nothing about case sensitivity, format constraints, or whether partial matches are accepted.

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 pairs a specific verb (return) with a specific resource (the full sourced profile of one provider) and keys it to a single identifier, so it clearly cannot be confused with list_providers or the page/site siblings. It stops short of naming the sibling it replaces, which keeps it from a 5.

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: an agent can infer it should call this when it already has a provider slug and wants a single record, versus enumerating with list_providers. There is no explicit when-to-use or when-not-to-use statement, and no mention of behavior when the slug is unknown.

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