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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely new context beyond the annotations: the corpus is a closed set of original (non-official) practice questions and the return value is task IDs rather than full tasks. It stops short of describing result count defaults or empty-result behavior.

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 compact sentences: the first front-loads what is searched and over what scope, the second covers the return value and the disclaimer. No filler, every clause carries information.

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, the description helpfully states the return format (task IDs) and the retrieval path. The main residual gap is parameter behavior for query/limit and questionType, but given a mostly-optional 0-required-parameter tool, the description is sufficient for correct invocation.

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 only 25% (only 'query' is documented), so the description must compensate. It partially does by enumerating the format categories that map to the 'format' enum, but adds nothing about 'questionType', the default/max on 'limit', or how 'query' matching works. Baseline 3 is appropriate given the partial compensation.

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 (Search) and a precise resource (original IELTS-style writing practice questions) with the covered scope spelled out (Academic Task 1/2, General Training Task 1/2). It also explicitly names the follow-up tool get_practice_task and disclaims official exam content, so an agent can distinguish it from siblings like search_vocabulary and get_sample_answer.

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 phrase 'Returns task IDs for get_practice_task' establishes the intended workflow (search first, then fetch detail), which is strong contextual routing. 'Not official exam questions' sets an expectation boundary, but there is no explicit when-not-to-use guidance or statement of what to do when the search returns nothing.

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