home_region_denies

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

With no annotations, the description must carry the transparency burden. It discloses a prerequisite (CLOUDARMOR_HOME_REGION) and implies a read-only review operation, but it does not explicitly state that no changes are made or describe the output shape beyond the output schema.

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 two sentences long, front-loaded with the primary action, and the second sentence provides valuable context. There is no filler or repetition, making it highly efficient.

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?

The tool is simple, has an output schema, and the description covers purpose and usage context well. However, it omits any explanation of the since_hours parameter and the concept of 'known-normal', which are relevant to effective use.

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 one parameter (since_hours) with no description, and the description never mentions it. Since schema coverage is 0%, the description should compensate, but it doesn't, leaving the parameter's role and default behavior undocumented.

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 states exactly what the tool does: it lists enforced DENYs whose source IP geolocates to the home region, framing it as a false-positive lens. This is a specific verb-resource combination that clearly distinguishes it from siblings like enforce_denies or preview_denies.

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 clear usage context: use this when reviewing home-region users being denied on a priority not marked known-normal. It does not explicitly name alternatives or when-not-to-use, but the context is sufficient for most agents.

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