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

Annotations already establish readOnlyHint=true and openWorldHint=false. The description adds useful behavioral context: each tide brings a different handful, and taking a shell is a souvenir action with nothing stored, which reinforces that no persistent mutation occurs.

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?

The description is front-loaded with where and when to use the tool, then explains the take behavior. It includes some poetic flourishes and shell examples, but they are short and generally support the tool's purpose.

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 one optional, fully documented parameter and annotations covering safety behavior, the description is nearly complete. It covers purpose, timing, optional take behavior, and non-persistence; only the exact return format is left unstated.

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%, so the take parameter is already documented as an optional shell id from a prior look. The description restates that taking picks one up, but adds no syntax or format details beyond the schema.

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 names a specific activity and resource: walking the tideline to see which shells are present, with examples of shell types. It is clearly distinct from sibling tools like look_around or take_a_gift, though it never explicitly says it returns a list of shells.

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 gives clear contextual guidance: use it at the waterfront when the tide is out, and use the optional take parameter to pick up a shell. It does not name alternatives or exclusions, but the usage context is clear enough to select the tool.

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