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

There are no annotations, so the description must carry the behavioral burden. It usefully states that the result includes subject, text, printable HTML, and a mailto link, and clarifies that PagoFix sends nothing and the creditor sends from their own mailbox. It still does not discuss permissions, rate limits, or legal caveats.

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?

The description is compact and front-loaded: step definitions and languages appear first, followed by return values and the sending responsibility. Every sentence adds distinct information, and there is no filler.

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 complex 28-parameter legal drafting tool with no annotations and no output schema, the description does well to document return shape and no-send behavior. However, it leaves important input semantics and workflow alternatives insufficiently covered, making it only minimally complete for 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 description coverage is only 36%, so the description should compensate for many undocumented parameters. It adds meaning for step and lang, but does not explain most of the 28 parameters, including key required fields such as amount, invoiceDate, creditorCountry, and debtorCountry beyond their schema labels.

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 uses a specific verb and resource: draft a reminder letter, with detailed meanings for steps 1, 2, and 3, supported languages, and returned artifacts. It is very clear, but it does not explicitly distinguish itself from siblings such as calc_claim or draft_eop.

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 implied workflow timing for each step (day 3, day 10, day 17), which helps the agent choose a step. However, it does not state when to use this tool instead of calc_claim, draft_eop, or get_status, nor does it include exclusions or prerequisites.

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