getKeyMetricsTTM

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

Annotations already provide readOnlyHint, idempotentHint, openWorldHint. The description adds that it retrieves trailing twelve-month data including profitability, efficiency, and liquidity, which aligns with annotations. It does not contradict annotations but adds limited behavioral context beyond them.

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 two sentences (45 words), front-loaded with the main action, and every sentence adds value. No waste, efficient communication.

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 single-parameter tool with good annotations, the description adequately explains the data scope (TTM metrics across profitability, efficiency, liquidity). However, it could list example metrics for more completeness since no output schema is provided.

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?

The input schema has 100% coverage with a description for 'symbol'. The tool description does not add additional meaning beyond the schema's 'Stock symbol' description, so baseline score applies.

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 it retrieves TTM key performance metrics covering profitability, capital efficiency, and liquidity. It distinguishes from siblings like 'getKeyMetrics' (likely non-TTM) and 'getKeyMetricsTTMBulk' (bulk) by implication, but does not explicitly differentiate.

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 implies use for detailed financial health analysis over the past year, providing context. However, it lacks explicit guidance on when to use this specific tool versus siblings (e.g., for single symbol vs. bulk) and does not mention exclusions.

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