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

Annotations already cover the safety profile (readOnly, idempotent, closed-world). The description adds genuinely new behavior: a one-hour cache, alphabetical ordering of `loot_sources`, and the exact fields returned (`id`, `name`, `drop_count`) — useful for deciding whether the data is fresh enough.

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?

Short and front-loaded: the core statement comes first, then the payload shape, then the cache note. Minor awkwardness from the mid-sentence line breaks, but no filler sentences.

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?

With no output schema, the description carries the burden of describing the return value and does so for the distinctive part (`loot_sources` fields and ordering). The remaining monument fields are deferred to `/monuments` rather than enumerated, which is a small but real gap for an agent that cannot see that other response.

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 coverage is 100% and the `slug` parameter already documents itself with an example (`airfield`) and a pointer to `/monuments`. The description adds no format or validation detail beyond the schema, 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 precisely what is returned: a single monument plus its `loot_sources`, and distinguishes it from the collection endpoint (`/monuments`). The distinction from `list_monuments` is implied through the endpoint reference rather than named directly, so an agent must map `/monuments` to `list_monuments` itself.

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?

Makes clear this is the single-record counterpart to the list endpoint and tells the agent how to follow up on each loot source (`/loot-tables/{id}`). It does not state exclusions or prerequisites, but for a simple lookup the usage context is unambiguous.

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