Sector

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a genuinely useful behavioral constraint by repeating that the key is a sector key and not a ticker, preventing a common misuse. It does not mention limits or error behavior, but with annotations the bar is lower.

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?

Front-loads the core action and follows with return contents and routing guidance, all of which earn their place. The 'not a ticker' warning is stated twice (once parenthetically, once as a closing line), which is mild redundancy.

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, so return values need not be explained, and the description still usefully previews them. It covers the drill-down path to get_industry and screen. Nothing essential is missing for a two-parameter, read-only browse tool.

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%, and the schema already enumerates every valid sector key plus the limit bounds, so baseline is 3. The description's examples ('technology', 'healthcare') and the key-vs-ticker clarification add only marginal value beyond the schema.

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+resource ('Browse a market sector') and disambiguates it from its siblings by explaining the key is a Yahoo sector key, not a ticker symbol. An agent can tell it apart from get_industry, get_market, and search without opening a 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?

Explicitly routes the agent onward: industry keys feed get_industry for drill-down or screen as an industry filter. This gives clear context and named alternatives. It does not state exclusions (e.g. when to prefer get_market instead), so it stops short of a 5.

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