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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds valuable context beyond that: it performs no new queries but 'composes the built-in references,' i.e., an aggregation over existing country/freedom/device/install data, and it lists the sections returned. Return format details are left to the output schema, which is fine.

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, no waste: the trigger condition is front-loaded, followed by the scope enumeration and the composition note. Every clause 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?

An output schema exists, so return values need not be explained, and the description covers the trigger, scope, and aggregation semantics. For a read-only composite tool with fully documented parameters, nothing an agent needs to select or invoke it is missing.

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 all three parameters (country, os, device_model) are already documented in the schema, including the ios default and the enums. The description only implicitly maps 'device check' and 'install steps' to device_model and os, adding marginal meaning. 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?

Names a specific resource (a data-related trip checklist) and enumerates exactly what it covers: networks, eSIM support, internet freedom, device check, install steps. It also states it 'composes the built-in country, freedom, device and install references,' which distinguishes it clearly from the many leaf siblings like check_device_compatibility or check_internet_freedom.

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?

Gives an explicit trigger: 'Use when the user is preparing a trip and wants one pass over everything data-related for a country.' This implies it is the aggregate alternative to invoking the individual check tools. There is no explicit when-not-to-use statement, but the composition sentence effectively signals that leaf tools are the alternative for narrower needs.

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