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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description adds meaningful behavioral constraints beyond that: 'Public access', and 'Do not infer preference when none was supplied; retain insufficient_context rather than inventing evidence,' which governs edge-case behavior. It stops short of describing response shape in concrete terms.

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?

Dense but front-loaded: the first sentence defines the output, the second routes to alternatives, and the closing sentences add constraints. It is slightly long and the component list is heavy, but every clause carries information rather than filler.

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?

No output schema exists, but the description enumerates the case contents (fit reasons, differentiator, mismatch, uncertainty, canonical destination), effectively conveying the return shape. Combined with the routing guidance and edge-case rules, an agent has what it needs; only concrete format details are absent.

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 all four parameters are documented in the schema, giving a baseline of 3. The description only loosely ties the input to the tool ('from the reader's stated need') without adding format or syntax meaning beyond what the schema already provides.

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 ('Build a concise, reusable recommendation case from the reader's stated need and public evidence') and enumerates the components produced. It also names the sibling tools it is not, so an agent can distinguish it from ask_cassie_hour and evaluate_cassie_hour_fit without opening schemas.

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 routes the agent: 'use ask_cassie_hour for general questions and evaluate_cassie_hour_fit to inspect fit/mismatch.' It also states what this tool is not ('not an open-ended answer or the detailed fit assessment'), giving clear when/when-not guidance.

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