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

No annotations are provided, so the description carries the full burden. It hints at an output ('the on-site comparison URL') but never states that the tool is read-only, whether the call is idempotent, or what happens if a slug is unknown. For a zero-annotation tool this leaves meaningful behavioral gaps.

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 with no filler, pairing the operation with the identifying key immediately. It is slightly terse rather than padded, which is preferable, but the brevity is what costs it the full clause on usage.

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 two-parameter read tool with no output schema, the description tells the agent what goes in and that a comparison URL comes out, which is roughly the minimum viable. With no annotations and no output schema, a bit more on result shape or failure modes would have been needed for a 4.

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 description coverage is 100%, and both parameters are documented in the schema as 'First/Second provider slug'. The description's 'by slug' phrasing adds no semantics beyond that, so the schema does the work and 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 verb ('compare') and resource ('two hosting providers') and names the identifying key ('by slug'), so the agent knows exactly what the tool operates on. It does not distinguish itself from the sibling get_provider_info, which could plausibly be used to look up providers as well, so it falls short of 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?

There is no statement of when to choose this tool over get_provider_info or search_servers, and no prerequisites (e.g. that both slugs must already exist). The agent must infer usage from the name alone.

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