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

Annotations already establish readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: it is purely descriptive content, returns structural exam data plus scoring criteria with word limits, and includes links out to ScoreFluent guides. It does not discuss caching, size or pagination, but for a static reference lookup that is a minor gap.

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?

Three sentences, front-loaded with the usage triggers, then the return contents, then the exclusion. The trigger list is long but each item corresponds to a real query the agent might receive, so it earns its space. Slightly dense but no 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?

An output schema exists, yet the description still summarizes the return shape in enough detail (sections, task types, counts, limits, scoring criteria, links) that an agent knows what it will get. Combined with the clear usage triggers and the explicit non-scoring boundary, nothing needed to call this correctly is missing.

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 both parameters (the exam enum and the optional taskType slug) are already documented in the schema. The description hints at the narrowing behavior by mentioning task-type-level scoring detail, but adds no format or syntax guidance beyond what the schema supplies. Baseline 3 applies when the schema carries the parameter burden.

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 resource (English exam structure) and enumerates exactly what the tool returns: sections, task types, question counts, time limits, scoring criteria and guide links. It also explicitly separates itself from the scoring siblings by stating it does not score or mark answers, so an agent can distinguish it from score_writing without opening any schema.

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 concrete trigger conditions (student asks what an exam contains, how a task type is scored, how long a section is, what the score scale is, where to start preparing) and an explicit when-not clause ('Do not use this to score or mark a student's answer'). That negative case implicitly routes the agent to score_writing, covering both sides of the decision.

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