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

With no annotations, the description must carry the behavioral burden. It only states subject matter and does not disclose what happens when called, what output is produced, or whether it is a read-only informational tool. This is a material gap because the agent cannot predict behavior from the text alone.

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?

The description is a single short sentence with no filler, and the title front-loads the 'what is compared' idea. It loses a point for awkward phrasing and for relying on the title to supply the implicit action.

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 zero-parameter informational tool the description is reasonably scoped, but without an output schema or annotations it does not state whether it returns a list, a table, or an explanation. The agent can infer purpose but not the exact behavior or return shape.

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?

The schema has zero parameters, so the baseline is 4. The description adds useful domain context about criteria and filters, and there are no parameter details for it to document.

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 identifies the resource as the criteria and filters used in comparing UK payroll software for small/medium employers, which is specific enough to distinguish from sibling comparison tools at a high level. However, it is phrased as a noun phrase rather than an explicit verb action, so an agent must infer that the tool returns or describes these criteria.

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?

The description gives no guidance about when to invoke this tool versus siblings such as compare_options or compare_table, and it names no alternatives or exclusions. Usage context is only implied by the tool's name and title.

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