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

Annotations already cover the safety profile (readOnly, idempotent, closed-world, non-destructive), so the description's job is added context, and it delivers: rows carry period start/end dates, a reported-vs-derived flag, and source document ids, plus the expectation to cite them. Units ('items') and the default/at-most row count are mentioned, though the row cap comes from the schema.

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?

Two tight sentences with no filler, leading with what the tool returns and following with the row-shape and citation requirement. Dense but always front-loaded.

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?

There is no output schema, so the description must explain return values, and it does: rows with periods, reported/derived status, and source ids. Combined with a fully documented 9-parameter schema, an agent has enough to call it correctly, though it could say more about ordering or pagination beyond limit.

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 every parameter is already documented, including the 'at' snapshot override and frequency defaults. The description only echoes period/item filtering and the units concept, adding little beyond the schema, so baseline 3 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 names a specific resource and scope: figures of one statement for one company, from its latest snapshot, filtered by period and item. That is clearly distinct from get_ratios and get_snapshot_info, though no sibling is named explicitly.

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?

Usage is implied: filter by period and item, and cite the snapshot and source document id in the output. There is no explicit guidance on when to prefer this tool over get_ratios or get_snapshot_info, and no exclusions or prerequisites are stated.

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