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

With no annotations and no output schema, the description carries the full burden, and it does disclose the shape of each entry (word, English meaning, underlying trout behavior). It doesn't state whether the result is a complete dump versus paginated, or give a sense of size, but for a zero-parameter reference tool the behavioral picture is largely sufficient.

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 with no filler. Every clause (word, English meaning, trout behavior) conveys distinct information about the payload.

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 parameterless read of a fixed glossary, the description says what the tool contains and what each entry includes, which is enough to call it correctly. Without an output schema it could say slightly more about return format or volume, but nothing critical 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?

The tool takes no parameters, so there is nothing for the description to disambiguate; the schema is empty and 100% covered. Baseline 4 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?

The description makes clear this is a complete glossary: every Troutish word paired with its English meaning plus the trout behavior it derives from. It is distinguishable from siblings like trout_dad_joke or trout_diary by being a vocabulary reference rather than content generation, though it never uses an explicit verb like 'list' or 'return'.

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?

Usage is implied rather than stated: an agent can infer this is the lookup for Troutish vocabulary, but there is no explicit guidance on when to call it versus answer_trout_question or talk_to_trout, which could plausibly surface the same terms. No exclusions or preconditions are given.

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