ons_geo_cache_status

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

Annotations already carry readOnlyHint=true and idempotentHint=true, so no additional safety disclosure is needed. The description adds the scope of what status is returned (cache/index for ONS datasets) but does not elaborate on behavior such as whether the status check triggers cache building or how staleness is reported; with the safety profile covered, the description provides adequate but not rich behavioral context.

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?

A single, front-loaded sentence states exactly what the tool does, lists the relevant dataset codes, and contains no filler. 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?

This is a simple, parameter-free status tool with a provided output schema and safety annotations; the description covers its functional scope and dataset focus. It could optionally mention what 'status' means (e.g., last build date, loaded indicator), but the output schema likely fills that gap, and the tool is straightforward enough 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?

The input schema has a single constant 'tool' parameter with no description, and zero required parameters, so effectively the tool takes no meaningful user input. Schema description coverage is 0%, but the description doesn't need to explain parameters because there is nothing to configure; the baseline for near-zero parameters is 4.

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 a specific verb ('Return'), a concrete resource ('cache/index status for ONS geography lookups'), and explicitly names the datasets (ONSPD/ONSUD/NSPL/NSUL). This differentiates it from the sibling admin_lookup_get_cache_status by naming the ONS domain and dataset codes.

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 context about the tool's scope ('ONS geography lookups' with specific datasets), which implies when to use it over the admin-lookup sibling. However, it does not explicitly state 'use this for ONS cache status, use admin_lookup_get_cache_status for admin cache status' or provide exclusion conditions, so it falls short of a fully explicit routing.

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