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

While annotations declare readOnly, idempotent, and non-destructive, the description adds valuable behavioral detail: each identification carries its own coordinates, class, rubric, and sources, and crucially, 'a place the poem does not locate carries no coordinates at all'. This edge case goes well beyond the annotations.

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, each earning its place. The first delivers the action and a compact list of returned data; the second gives the use case and a key edge case. No filler or repetition.

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?

Given an output schema exists and annotations cover the safety profile, the description supplies the remaining needed context: when to use the tool and what data to expect, including the meaningful 'no coordinates' case. Nothing essential 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 coverage for parameters is 100%: slug is described with an example and locale has an enum and default. The description only says 'by slug', adding no new parameter meaning beyond what the schema already provides. 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?

The description opens with a specific verb and resource: 'Get one place by slug', then enumerates exactly what is returned (identifications, coordinates, class, 0-12 rubric, sources, attested passages). This clearly distinguishes it from sibling tools like get_homeric_episode, get_homeric_route, and list_homeric_places.

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?

It explicitly states the intended use: 'Use this when you need to weigh the evidence for a location, or to cite it'. This gives clear context for when to choose this tool, though it does not explicitly name alternatives or describe when not to use it.

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