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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful semantics beyond that: the sort order (newest first by latest_checked_at) and the distinction between checked_at (whole-record) and the field-level check date. It says nothing about result volume or paging behavior beyond what the schema already documents.

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?

Three tight sentences with no filler, and the scoping and ordering facts are front-loaded before the usage note. The clause about checked_at versus latest_checked_at is dense but load-bearing. Minor cost is that the opening reads awkwardly as a fragment rather than a direct statement of action.

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 read-only, three-parameter list tool with full schema coverage and no output schema, the description covers what is needed to call it correctly: the filter semantics, the ordering, and where to go for full record detail. Returned fields are not enumerated, but the annotations and schema carry most of the remaining burden.

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 limit, since and offset are already fully documented, including the omit-for-all-records behavior of since. The description reinforces the date semantics and supplies the ordering, but adds no format or edge-case detail the schema lacks. Baseline 3 is appropriate.

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 states a concrete scope: firms whose whole record or a published field was checked on or after a date, returned newest first by latest_checked_at. It explicitly disclaims what the name might suggest ('this is not value-change history') and separates itself from get_firm. The opening is a noun phrase rather than a clean verb, but the resource and filter are 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?

It gives a direct use case ('keep a copy of the data current') and names the alternative for the adjacent need ('fetch get_firm for the current record'). It also rules out using it as a change-history feed. What is missing is any guidance on when to prefer this over something like search_firms or list-based paging workflows.

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