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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds useful context beyond that: the return shape (letter text plus page and PDF/TXT download links) and the caveat that these are adaptable templates rather than legal advice. It does not discuss coverage limits, letter counts, or what the list response looks like.

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 sentences, front-loaded with the primary list behavior and followed by the return format and disclaimer. The parenthetical list of example appeal reasons is longer than strictly necessary but does aid selection.

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 one-optional-parameter read-only tool with no output schema, the description covers both invocation modes, the content of results, and the intended use of the material. Only minor gaps remain, such as list size or pagination, which are unlikely to block correct invocation.

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% and the parameter description already explains that omitting letter_id lists all letters while supplying an id retrieves one. The description's mention of returning 'the text of one letter' reinforces the two modes but adds no syntax or format detail beyond the schema, so the baseline of 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 states a specific verb and resource ('Lists Parksy sample letters for appealing a parking ticket') and also covers the second mode ('returns the text of one letter with its page and PDF/TXT download links'). The enumeration of appeal reasons makes the resource concrete and clearly separable from siblings like fine_appeal_check or parking_guides.

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 clear usage context (appealing a parking ticket) and frames the material as 'Templates to adapt, not legal advice', which tells the agent how to present results. It does not explicitly name alternatives such as fine_appeal_check, so it stops short of full when/when-not routing.

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