search_by_category

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, indicating safe read-only behavior. The description adds value by explaining the return format (Markdown table of tool names and descriptions) and the error case for unknown categories, which are not covered by annotations.

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 uses a structured docstring format with Args and Returns sections, which is clear and organized. It is appropriately sized—short but informative—though the Args section slightly duplicates the schema description. No unnecessary sentences.

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?

Given the tool's simplicity (single parameter, no nested objects, output schema present), the description is fully complete. It covers purpose, input, output format, error handling, and references a prerequisite tool (list_categories). It provides all necessary information for an agent to use the tool correctly.

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 100% schema coverage for the category parameter, the description adds significant value by providing concrete examples ('e.g., ratios, technicals, economics, discovery') and referencing list_categories to clarify valid inputs. This goes well beyond the schema's generic description.

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 clearly states the tool lists every available metric/tool within a category, specifying the action (list) and resource (metrics/tools by category). It distinguishes from sibling tools like search_metrics (which likely search across all metrics) and specific category tools by being a general listing tool.

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 implicitly advises using list_categories first to get valid category names, as it mentions 'category: One of the category names returned by list_categories'. However, it does not explicitly state when to use this tool versus alternatives like search_metrics or specific category tools, nor does it include any 'when not to use' guidance.

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