test_url_category

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context: it specifies the data source (PAN-DB from local cache and cloud), and explicitly states what is NOT included (custom categories). It also implies the tool performs a live query against a firewall. A small gap: it doesn't mention whether this triggers any network traffic or has latency implications, but the read-only annotation covers the main concern.

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 zero waste. The read-only marker is front-loaded, the core function is stated immediately, and the exclusion/alternative is given in the second sentence. 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 query tool with 100% schema coverage and no output schema, the description is nearly complete. It covers what the tool does, what it doesn't do, and which sibling to use instead. The only minor gap is that it doesn't describe the return format or whether the result includes both cache and cloud results separately, but the output schema is absent and the tool is simple enough that this is a minor omission.

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 four parameters thoroughly. The description adds the context that the 'device' parameter can be omitted because PAN-DB is the same everywhere, which is a useful semantic addition. However, most parameter meaning is already in the schema, so the description doesn't need to compensate much. Baseline 3 is appropriate.

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 clearly states the tool's purpose: it asks a managed firewall how it categorizes a URL, specifically PAN-DB categories from local cache and cloud. It also explicitly distinguishes itself from url_category_find by noting custom categories are not shown here. This is a specific verb+resource with clear differentiation from siblings.

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 explicitly says when to use this tool (to test URL categorization) and when not to (custom categories are not shown here, use url_category_find instead). It names the alternative tool directly, giving the agent clear routing guidance.

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