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

Annotations already declare readOnlyHint/idempotentHint, so the closing 'Read-only' adds nothing. What does add value is the disclosure of result-shaping behavior: at most six cases, each carrying the user's best mock-interview score, plus the three latest mock interviews and their scores. The exact ordering/filter semantics remain ambiguous, which keeps this below a 5.

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 intent sentence is front-loaded, but the long middle clause stacks 'up to six', 'walked through ... first', 'best score' and 'three latest mock interviews' into one hard-to-parse run-on. An output schema exists, so the space spent enumerating return contents could have been trimmed.

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?

Return shape needn't be described given the output schema, and the sibling routing is present. However, for a list tool the selection and ordering rules are the core contract, and the description leaves it unclear whether only previously-practiced cases are returned or all cases are returned ranked by practice score. That ambiguity is a meaningful gap for an agent deciding whether to call it.

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% and the single 'topic' parameter already has an enum and a description ('leave it out for every topic'), so the schema carries the full burden. The description never mentions topic filtering, so it adds no meaning beyond the structured field. Baseline 3 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?

Opens with a specific verb+resource ('List real product cases') and defines what a case is ('a company's decision, from public sources'), which separates it from get_practice and start_mock_interview. The qualification clause ('those the user has walked through in a mock interview first with their best score') muddies whether cases are filtered or merely ordered, so the scope is not fully crisp.

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 it to pick a case, then start_mock_interview to practice it; STAR answer practice is in get_practice.' That names both the downstream tool and the sibling covering a different need. It stops short of stating when not to call it (e.g. if the user already has a case in mind).

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