Measure history

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

Annotations already declare readOnlyHint/idempotentHint, so safety is covered. The description adds non-obvious traits: results are newest-first and long answers are paginated, plus the semantics of the as-of basis. It doesn't state page size defaults or how to fetch subsequent pages, which keeps it from a 5.

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 scope, then the alternative, then pagination. Dense and zero filler, though the phrasing around basis is a compressed list that reads slightly telegraphically.

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?

With a full output schema and rich param descriptions, the description carries the routing and paging burden well. The main omission is guidance on pagination mechanics, but that is minor for a read-only listing 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 coverage is 100%, so baseline is 3. The description clarifies the basis concept (latest/first reported/as known on a filing date) and that concepts takes multiple measures, but these largely restate enum values already documented in 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 (get a measure over time), the scope (one or several measures via concepts), ordering (newest first), and the three basis variants. It also explicitly names financial_statements as the sibling it is not, so an agent can discriminate without opening schemas.

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?

Gives an explicit when-to-use clause ('one measure across periods or as known on a past date') and an explicit redirect ('financial_statements for whole statements'). The condition that selects the alternative is spelled out.

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