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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without the description. The description adds no further behavior (no not-found handling, no path/permission notes), so it neither helps nor harms.

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?

One short sentence with the key-resource relationship front-loaded and no filler. It is efficient, though it is arguably too terse to earn a top mark given the tool surface it could describe.

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 fetch with a fully documented one-parameter schema and annotations covering safety, nothing essential is missing. No output schema exists, but the return shape of 'an FCI history entry' is self-evident from the name.

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% for the single required 'id' parameter (uuid, 'FCI history entry ID'). The description's 'by ID' merely restates the schema, so 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 and resource ('Get a single site FCI history entry') plus the lookup key ('by ID'). The word 'single' implicitly separates it from the list_site_fci_history sibling, but the sibling is never named, so the differentiation relies on inference.

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?

Calling with an ID is implied as the use case, but there is no explicit when-to-use statement and no pointer to list_site_fci_history for the browse/enumerate case. Usage is inferable rather than stated.

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