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

The description aligns with annotations (readOnlyHint=true, idempotentHint=true, destructiveHint=false) and adds domain context about which attributes the record contains. However, it adds no beyond-annotation behavioral detail such as what happens when an id/name is not found, whether partial name matches are accepted, or any lookup constraints. With annotations already covering the safety profile, the extra context is modest.

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 with no filler: the first front-loads the core purpose and enumerates the returned fields in a compact list, and the second conveys the input form. Every phrase earns its place, and the structure makes the tool's scope immediately scannable.

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 simple, single-parameter, read-only tool with full schema coverage and rich annotations, the description is nearly complete. It tells the agent what the call returns (the listed record attributes) and what input to provide. The only minor gap is not defining what 'Percolate' refers to or how name matching behaves, but these are small omissions for a low-complexity lookup.

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 input schema already fully documents the single parameter with a description and an example. The description's sentence 'Accepts a Percolate id or a name' mostly repeats schema content, adding only the qualifier 'Percolate' to clarify the id type. Since schema_description_coverage is 100%, the baseline of 3 is appropriate; the description provides marginal extra meaning.

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 clearly states the tool's function: fetching a detailed record for exactly one coffee, listing its constituent fields (roast level, flavor notes, price, etc.). The phrase "one coffee" plus the listed fields cleanly distinguishes it from siblings like search_coffees or compare_coffees, so an agent can select it without ambiguity.

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?

The usage context is implied rather than explicit: when you have a specific Percolate id or a coffee name and want full details, use this tool. It does not name alternate tools (e.g., 'use search_coffees when you lack an exact id or name') or state when not to use it, so exclusion rules are left to inference.

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