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

Annotations already mark the tool as read-only, idempotent, and non-destructive. The description adds valuable behavioral facts beyond those: the download link expires after one hour, and the export is atomic—no partial file is produced if a limit is hit. This is strong contextual disclosure.

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 short sentences, front-loaded with the action and return value, followed by an important caveat. Every sentence earns its place with 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?

Core behavior and key caveats are present, and required parameters are clear. However, the optional filter parameters are left undefined, and the nature of the 'limit' is unspecified, so it is not fully complete for a 7-parameter tool without an output schema.

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 only 43%, and the description adds little beyond the schema: 'date range' and 'csv, xlsx or json' restate from/to/format. It does not explain the meaning or effect of project, billable, category, or path, which are undocumented in the schema.

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 ('Export'), a resource ('expenses'), a required date range, supported formats, and the return type (download link). It is unambiguous, though it does not explicitly distinguish itself from sibling tools like expense_list or expense_summary.

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?

The description implies when to use the tool: when expense data needs to be exported in a file format. However, it gives no explicit when-not-to-use guidance, prerequisites, or references to alternative tools.

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