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

Annotations already establish readOnlyHint, idempotentHint and non-destructive behavior, so the bar is lower. The description adds genuinely useful context the annotations do not cover: returned amounts are bare numbers with no currency, and currency_code must be fetched separately. That is a meaningful behavioral caveat for an agent reporting values.

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 tight sentences with the core purpose front-loaded and the currency caveat second. No filler, though the currency note is somewhat tangential to a 'get site' call and slightly dilutes focus.

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 simple single-record read with full annotation coverage and no output schema, the description covers purpose, key returned fields, and the currency caveat. It is largely self-sufficient; only sibling differentiation and any not-found/error behavior are absent.

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?

With a single id parameter at 100% schema description coverage, the schema fully documents the input ('Site ID', uuid format/pattern). The description adds nothing about the id itself, so the baseline 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+resource ('Get detailed information about a specific site') and names the fields returned (address, description). It distinguishes itself implicitly from list_sites by scoping to 'a specific site', but never names the sibling, so it stops short of full differentiation.

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?

There is no explicit when-to-use or when-not-to-use guidance relative to list_sites or get_site_fci_history_entry. The second sentence does route the agent to another tool (get_organization_settings) when currency context is needed, which is a useful cross-tool instruction, but it is a data-interpretation rule rather than invocation guidance.

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