get_index_values

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

No annotations are provided, so the description carries the full burden. It discloses that the tool supports pagination, sorting, and date range filtering, and that it returns historical values (implying a read-only operation). However, it does not provide deeper behavioral context such as default time ranges, pagination token usage, or any side effects. This is adequate but minimal for a read tool.

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 long, front-loaded with the core purpose, and every sentence earns its place. It avoids redundancy and is easily scannable.

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 tool has an output schema and six parameters, so the description does not need to explain return values or parameter details. It covers the high-level capabilities (historical values, pagination, sorting, date filtering) relevant for selection and initial invocation. It does not mention edge cases like defaults for 'start' and 'end', but those are documented in the schema, making the description sufficient for its purpose.

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%, so the input schema already documents all parameters thoroughly. The description's only parameter hint is 'Provide a comma-separated list of index symbols,' which duplicates the schema description for 'symbols' and adds no new meaning. Therefore, the description adds no value beyond the schema, matching the baseline.

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 a specific action: 'Returns historical values for market indices over a time interval.' This distinguishes it from the sibling tool get_index_latest_values by emphasizing 'historical' values, making the purpose unambiguous.

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 provides clear context: it is for historical index values with date range filtering, pagination, and sorting. It also instructs the user to 'Provide a comma-separated list of index symbols.' While it does not explicitly name alternative tools for latest values, the phrase 'historical values' implicitly guides usage away from get_index_latest_values.

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