url_category_list

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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description reinforces this with '[READ-ONLY]'. It adds useful scoping context (shared/device groups, type and entry count) but does not disclose details such as pagination, result limits, or empty-result behavior. That is acceptable given the strong annotation coverage, but not exceptional.

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?

Two sentences with no filler. The first sentence front-loads action, scope, and output characteristics; the second sentence routes the agent to the relevant sibling. Every word earns its place.

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 read-only list tool with no required parameters and no output schema, the description covers purpose, scope, and the information returned. It also handles the main sibling distinction. It does not describe edge cases or exact result structure, but nothing critical is missing for correct invocation.

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%, so the schema already documents all three parameters (firewall, device_group, name_contains). The description adds no parameter-level guidance beyond the general listing purpose, so the baseline of 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 and resource ('Lists custom URL categories'), clarifies scope ('shared and device groups'), and mentions the returned information ('type and number of entries'). It also distinguishes itself from the obvious sibling url_category_get by pointing to that tool for entries.

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?

Explicitly names the alternative tool and the condition that selects it: 'Use url_category_get for the entries.' This gives an agent a clear decision rule between listing categories and fetching their entries. The description does not mention every related sibling, but the main ambiguity is resolved.

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