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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds valuable behavioral context beyond the annotation: it returns a specific shape ({path, title, chunks}[]) and clarifies that it is enumeration, not content search. It does not contradict the annotations. Minor gap: it doesn't mention whether chunks are full content or summaries, but the read-only nature is clear.

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 description is three sentences with no wasted words. It front-loads the primary action, provides usage timing, excludes confusing alternative uses, and gives the return shape. Every sentence earns its place.

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?

For a two-parameter read-only discovery tool with no output schema, the description is mostly complete: it states purpose, usage timing, exclusions, and return format. The only notable incompleteness is the ambiguous namespace parameter semantics, which prevents a perfect score. Overall, an agent has enough context to use the tool correctly in most cases.

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 0%, so the description must carry the burden of explaining parameters. The description only says 'in a category/namespace,' which mentions both parameter names but does not explain what a namespace is, how it interacts with category, or what happens when neither is provided. The enum for category is self-explanatory, but the namespace string remains ambiguous. This is a significant gap given the lack of schema descriptions.

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 opens with a specific verb and resource: 'Enumerate doc paths in a category/namespace.' It clearly distinguishes itself from content-search siblings by explicitly saying 'NOT a content search' and naming semantic_search and grep_docs as alternatives. This makes the tool's purpose unmistakable.

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 description explicitly states when to use this tool: 'Use to discover what exists before calling get_document or a targeted grep_docs.' It also provides clear exclusion guidance: 'NOT a content search — use semantic_search for behavior/concept lookups or grep_docs for token lookups.' This is model guidance for tool selection.

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