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

Annotations declare a safe read (readOnlyHint=true, destructiveHint=false), but the description goes well beyond them: results have passed planning/block and pricing checks, results intentionally omit images, the 30-result display policy, and the rule that missing length/beam must be omitted rather than zeroed, estimated, or used to exclude yachts. This is rich behavioral context the annotations do not carry.

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?

Front-loaded with the core purpose, then structured into distinct paragraphs for result-count policy, media routing, and missing-value handling. Every sentence carries a rule, though the length/beam paragraph is somewhat tangential to the actual parameter set and could be tighter.

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 and 13 parameters, the description compensates thoroughly by describing result behavior (30-result threshold, full-list vs. preference prompt, no arbitrary subsets, alternative suggestions), return-content limits (no images), and data-quality rules for missing fields. An agent has everything needed to call and interpret the tool.

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%, so the schema already documents all 13 parameters (pax, price, boat_model, etc.) and the baseline is 3. The description adds only marginal param meaning, notably that 'base' must be an official Base_list name and that dates are the exact requested dates; length/beam it discusses are not even parameters here.

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 ('Search Sedna for yachts available for the exact requested dates') with scope qualifiers (date-availability, passed planning/block and pricing checks). It is clearly distinguishable from siblings like Base_list, boat_details, and booking_detail, which it names directly.

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?

Explicitly prescribes prerequisites and alternatives: 'Call Base_list first and use an official base name,' route photo/media requests to boat_details with id_boat, and use booking_detail for date-specific prices, extras, and ports. It also gives concrete branching rules for >30, <=30, and zero results.

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