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

Annotations already cover read-only/idempotent/open-world, and the description adds substantive behavior beyond them: 'Signed-in' auth requirement, and a prominent data-integrity caveat that counts reflect the mirror, not the office, with per-office `coverage` and `do_not_quote` fields flagging unreliable offices. This is exactly the extra context an agent needs before quoting numbers.

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-loaded with purpose, then invocation, then the caveat — a logical order with no filler. The mirror/coverage warning is somewhat dense, but every sentence carries decision-relevant information.

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 no output schema, the description still sketches the return shape (volume by month, busiest filers) and names output fields (`coverage`, `do_not_quote`) that govern interpretation. Combined with the auth note and caveat, an agent has everything needed to call and correctly read this 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 description coverage is 0%, so the description must carry the load, and it does: examples for nice_class (9, 42, 36…), 'office code' values for jurisdiction ('EM','US','GB','CH'), and the meaning of months as a window. It does not explain the empty-string jurisdiction default or reconcile that the schema calls the field 'jurisdiction' while the prose calls it an office code.

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?

Names a specific verb and resource: 'Filing activity in a Nice class — volume by month and the busiest filers.' An agent can tell this is a class-level aggregate. It stops short of explicitly distinguishing itself from the close sibling filer_activity, so a 5 is not earned.

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?

Frames the intent with 'Answers "how crowded is my space" and "who keeps filing near me"' and gives concrete invocation guidance (class, optional office code, window in months). It provides clear context but names no explicit alternative or when-not condition, so no 5.

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