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

Beyond the `readOnlyHint` annotation, the description discloses substring matching on the full path, default `limit` of 50, the exact return shape (`categories` with `hash`, `name`, `path`, plus `returned`, `total`, `taxonomyCode`, `taxonomyLocale`), and optional `project_id` inference. This provides substantial behavioral context that the annotations do not cover.

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?

Four dense, front-loaded sentences cover purpose, addressing modes, return format, parameter behavior, and downstream usage. There is no filler or redundant restatement of the annotations.

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?

The description is complete enough to invoke correctly: it gives return fields, parameter semantics, and the link to `set_category_mapping`. Minor gaps include not stating what happens when neither `feed_id` nor `taxonomy_code` is provided, and not explaining `returned`/`total` semantics beyond their existence.

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?

Despite only 50% schema description coverage, the description compensates strongly: `query` matches the full path with examples, `feed_id` selects the taxonomy, `taxonomy_code` is an alternative, `taxonomy_locale` has a default behavior, `limit` bounds results, and `project_id` is optional with inference rules. Every parameter gains practical meaning beyond its bare type.

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 resource ('feed's target taxonomy tree'), with the matching mode ('substring of the category path'). It also distinguishes itself from related tools by noting that the returned `hash` feeds into `set_category_mapping`. The purpose is unambiguous and not a tautology.

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?

Explains the two addressing modes—`feed_id` vs `taxonomy_code`—and notes `project_id` is optional and inferred for single-project customers. It also clarifies the downstream use case by telling the caller to pass a returned `hash` to `set_category_mapping`. It does not explicitly list exclusions or alternatives, but the usage context is clear.

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